Vaisala News 165 - Full Magazine

165/2004 

Report on 

the 2002-2003 U.S. NLDN ® 

System-wide Upgrade 

Exploring Long-range 

Lightning Detection 

over the Oceans 

Vaisala Radiosonde RS92 

on Trial in Italy 

Vaisala Upgrades 

Dubai International 

Airport

Contents 

President's Column 3 

Vaisala Remote Sensing 

Report on the 2002-2003 U.S. NLDN ® 

System-wide Upgrade 4 

Exploring Long-range Lightning Detection 

over the Oceans 9 

Vaisala takes part in the 84 th American Meteorological 

Society Annual Meeting in Seattle 11 

Vaisala Soundings 

Vaisala Radiosonde RS92 on Trial in Italy 12 

Vaisala HydroMet 

Chilean Navy Weather Service Invests in 

Vaisala Automatic Weather Stations 18 

Over the past two years, Vaisala has invested 

in the most comprehensive upgrade of the 

North American Lightning Detection 

Network to date. The upgrade included the 

installation of the new Vaisala IMPACT 

ESP Lightning sensors throughout the 

continental United States. The upgrade will 

improve the performance of the sensors, 

minimize maintenance and downtime and 

build a stronger base for future 

improvements. 

In May 2004 Vaisala's new clean room was 

taken into operation and the production of 

sensors was re-started. A clean room is a 

nearly particle-free area where air quality, 

temperature and humidity are carefully 

regulated to ensure that sensitive equipment is 

free from contamination. The new facility is 

state-of-the-art and will allow Vaisala to 

continue to produce high quality sensors for 

our products. 

Update of the Vaisala Automatic Weather Stations 

MAWS101 Monitoring Transmission Lines 19 

Hydrometeorological Real-time network in 

North-eastern Italy 20 

Co-operating to Improve 

Water Quality Measurements in Finnish Waterways 22 

The Vaisala Radiosonde RS92 family has 

been available on the market for over a year. 

In November 2003 and March 2004 testing 

was carried out in Italy to compare the PTU 

measurement performance of the Vaisala 

Radiosonde RS92 and the Vaisala RS90. 

Vaisala Road Weather 

Norwegian Roads Safer with Vaisala's 

Remote Measurement and Forecasting Technology 23 

Vaisala Aviation Weather 

Vaisala updgrades Dubai International Airport 24 

General 

Cover photo: 

Grand Canyon, Arizona USA 

Vaisala Invests 6.5 million Euros in New Clean Room 26 

Secretary General of the World Meteorological 

Organization Visits Vaisala 28 

In Vaisala 30 

Vaisala in Brief 

– We develop, manufacture and 

market products and services for 

environmental and industrial 

measurements. 

– The purpose of these measurements 

is to provide a basis for a 

better quality of life, cost savings, 

environmental protection, 

improved safety and better performance. 

– We focus on market segments 

where we can be the world leader, 

the preferred supplier. We put a 

high priority on customer satisfaction 

and product leadership. 

We secure our competitive advantage 

through economies of scale 

and scope. 

Editor-in-Chief: 

Angela Billings 

Publisher: 

Vaisala Oyj 

P.O. Box 26 

FIN-00421 Helsinki 

FINLAND 

Phone (int.): 

+358 9 894 91 

Telefax: 

+358 9 8949 2227 

Internet: 

http://www.vaisala.com 

Design and Artwork: 

Edita Prima 

Printed in Finland by 

Edita Prima, Finland 

ISSN 1238-2388 

NORDIC ENVIRONMENTAL LABEL 

441 002 

Printed matter 

2 165/2004

President’s Column 

Insource the core, 

outsource the context 

creasingly more expensive to 

maintain resources for that on 

the local level. 

The paradigm is changing 

and the key word today is service. 

I believe that our customers 

will increasingly need services as 

they begin to focus their resources 

on their core activities. 

At the same time they will increasingly 

want supporting services 

from a reliable partner. Our 

technical and application competencies 

give us a good position 

to take responsibility in system 

integration, maintenance, operations, 

financing, and to meet the 

ultimate needs of the customer: 

deliver high quality information 

and data. 

Vaisala has done similar 

things in our own industrial activity. 

We rely on competent service 

providers, who have devel- 

“Insource the core, outsource 

the context” is a 

business slogan, which is applied 

in many global companies. 

The key message is that in 

order to be competitive, resources 

should be focused on 

the core activities of the business, 

that is to say, to areas 

which generate a competitive 

edge. Non-core or context activities 

should be purchased 

from competent service 

providers. At times it is even 

better to take some of the core 

pieces from strategic partners, if 

you are unable to meet the volume 

required by that activity. 

I believe that this guidance 

applies equally well to the meteorological 

community. For 

most of our customers the ultimate 

need is weather observation 

data or further value 

added information, supporting 

operational decision making 

in a specific application. Activities 

such as integrating and installing 

a system, owning it, operating 

it and maintaining it, 

have all traditionally been 

mandatory in order to meet 

one's need for data or information. 

Those originally mandatory 

activities may have changed over 

time to become activities determined 

to be context. 

Technology development is 

also creating a push for change. 

Increasing automation makes 

equipment challenging to maintain 

and upgrade. During the 

equipment's lifespan upgrades 

can increase the value of data 

and information. Using the Internet 

enables new system architectures, 

where central processing 

can be done efficiently on a 

global level. More skills are needed 

to manage the recent developments 

in technology and it is inoped 

expertise by focusing their 

efforts on their core. A wide 

range of manufacturing activities 

belongs to this category. This 

transformation has helped us to 

develop our competitiveness 

and growth. 

I may have been a bit 

provocative above. But we have 

good experience already in 

many areas of shifting from being 

solely a provider of hardware 

to providing services and data. 

In the U.S we already provide 

lightning data to multiple applications. 

This will be an area to 

increase our offerings. 

Let's talk about it. ● 

Pekka Ketonen 

President and CEO 

165/2004 3

Michael J. Grogan 

Product Manager, 

Network Data and Software 

Vaisala 

Tucson, USA 

Vaisala's U.S. National Lightning Detection Network ® 

Report on the 2002-2003 

U.S. NLDN ® System-wide 

Upgrade 

Two years ago, Vaisala began an ambitious project to 

re-build the National Lightning Detection Network 

(NLDN) by replacing more than 100 early generation 

sensors with new, more sensitive lightning sensors to 

improve network performance and expand applications. 

Initial third-party validation studies indicate 

that the network is operating better than ever with 

minimum 90 percent flash detection efficiency. 


Over the past two years, 

Vaisala has invested in 

the most sweeping upgrade 

yet of the NLDN with the 

installation of new Vaisala IM- 

PACT ESP Lightning Sensors at 

sensing stations throughout the 

continental United States. These 

new sensors replaced more than 

100 of the first generation IM- 

PACT Lightning Sensors and 

older LPATS III Lightning Sensors. 

The main goals of the upgrade 

were to: 

● Improve network performance 

by using newer sensing 

technology 

● Minimize maintenance 

and sensor downtime by replacing 

aging sensors and sensing 

station equipment 

● Build a stronger base for 

future improvements, including 

cloud lightning detection opportunities 

Pre-Upgrade Operations 

In the early 1990s, the NLDN 

consisted of early generation 

magnetic direction finding sensors. 

The network detected 65 to 

80 percent of cloud-to-ground 

lightning discharges with location 

accuracy ranging from 2 to 

4 kilometers. 

The first major upgrade project 

to the NLDN began in 1994 

and was completed in 1995. 

Vaisala – then Global Atmospherics 

– partnered with the 

Electric Power Research Institute 

to improve network performance 

to produce operational 

benefits targeted at the electric 

utility industry. Electric power 

utilities needed more detailed information 

and more accurate 

lightning locations to design 

more effective lightning protection 

to improve the reliability of 

transmission and distribution 

systems. The focus of the 1994- 

1995 upgrade project was to: 

● Report strokes as well as 

flashes 

● Improve location accuracy 

● Increase percentage of 

lightning discharges detected 

● Report peak current estimates 

for cloud-to-ground lightning 

strokes 

The primary means to 

achieve these goals was to employ 

the latest lightning sensor 

technology; a combination of 

time-of-arrival and magnetic direction 

finding methods in a single 

sensor, the original IMPACT 

Lightning Sensor. At the completion 

of the 1994-1995 project, 

the network consisted of 47 of 

the new combined technology 

sensors and 59 of the existing 

time-of-arrival sensors. In central 

processing, the location and 

stroke processing algorithms 

were also refined and ➤ 

Image shows 24 hours of lightning data from the U.S. National 

Lightning Detection Network 

U.S. National 


Network ® Backgrounder 

Weather forecasters in both public and private 

sectors use real-time lightning maps and individual 

lightning stroke characteristics from the NLDN ® 

to closely monitor thunderstorm development, 

strength, and paths for more accurate severe weather 

forecasting and for issuing warnings. NLDN users include 

the National Weather Service, NASA, FAA, and 

other government agencies. Operations that are affected 

by lightning and thunderstorms – electric power 

utilities, airports, telecommunications, explosives handling 

and others – rely on NLDN lightning data to tell 

which facilities are at increased risk from thunderstorms. 

NLDN information is used for monitoring current 

conditions and for studying past events. Since 1989, the 

NLDN has reported more than 20 million cloud-toground 

lightning flashes that occur every year, creating 

a comprehensive archive of lightning data used for statistical 

and forensic analysis. 

NLDN data is available to subscribers through various 

lightning mapping software and Internet lightning 

tracking services. These application tools are specialized 

for real-time lightning tracking and warning or for 

analysis of past lightning activity. Real-time data is delivered 

by satellite broadcast or TCP/IP. Historic lightning 

data is delivered by CD or via traditional Internet protocols. 

● 


NLDN Timeline 

1984-1989: Three separate regional lightning networks 

develop and operate at various locations. These networks 

using early direction finding methods for lightning detection 

1989: Regional networks share data to establish a national 

network, the NLDN. This cooperative project is 

funded by the Electric Power Research Institute (EPRI) and 

operated by the State University of New York (SUNY) at 

Albany. For the first time, real-time data is available to 

users across the country. This will allow the first time ever 

improved. 

The result of the 1994-1995 

project was a new flash detection 

efficiency of 80 to 90 percent 

and 500-meter median location 

accuracy. The results of the 1994- 

1995 upgrade were verified by independent 

validation studies. 

Upgrade Calls for 

All New Sensors 

A combination of aging equipment 

and the desire to improve 

performance by using more advanced 

technology led to initial 

planning of the next systemwide 

upgrade. After more than a 

year of planning and development, 

work began in November 

2001 to install new and more advanced 

Vaisala IMPACT ESP 

Lightning Sensors throughout 

the network. The new sensors 

would replace the old sensors 

1991: Real-time and historic lightning data becomes 

commercially available. 

1993: NLDN Network Control Center is moved to its current 

location in Tucson, Arizona. 

1994: Comprehensive customer research leads to the development 

of new, more powerful lightning display and 

lightning analysis software. 

1995: First major system-wide upgrade completed with 

project partner EPRI. This upgrade added new lightning 

sensors that combined magnetic direction finding and 

time-of-arrival detection methods in a single sensor, the 

original IMPACT Lightning Sensor. NLDN began reporting 

flashes and individual return strokes within a flash. Flash 

detection efficiency increased to 80-90% with median 

stroke location accuracy of 500 meters. 

Today’s NLDN consist of 113 lightning sensor locations across the 

continental U.S. 

1996-1999: Commercial applications of historic lightning 

data proliferate in electric power, insurance, and 

other industries as a result of improved location accuracy 

and application-specific software developments. 

1998: The Canadian Lightning Detection Network, 

owned by Environment Canada, is completed. Operations 

for the CLDN are combined with NLDN operations in Tucson. 

The lightning data from the NLDN and CLDN sensors 

– close to 200 sensors –are processed on a single processing 

platform. 

2000: NLDN real-time and historic lightning data is available 

on the Internet in several application-specific formats. 

2003: Second major system-wide upgrade completed 

with replacement of aging sensors and earlier sensing 

technology with new, more advanced, third generation 

Vaisala IMPACT ESP Lightning Sensors throughout the 

network. Preliminary evaluations indicate overall minimum 

90% flash detection efficiency and 60-80% stroke 

detection efficiency. ● 

Distinguishing Flashes and Strokes 

NLDN lightning flash data provides time, location, polarity, 

first-stroke amplitude, and multiplicity of each cloud-toground 

lightning flash. However, research has shown that 

there can be up to 20 return strokes that make up a flash and 

these strokes often strike the earth in different locations up to 

several kilometers apart. NLDN stroke data provides time, location, 

polarity, and amplitude of these strokes, providing the 

very detailed data needed for in-depth lightning analysis and 

lightning incident investigations. Flash data is most often used 

for general trending of lightning events; stroke data is critical 

for understanding specific incidents. 

Key Performance Measurements 

• Median stroke location accuracy: 50 percent probability error 

for locating a cloud-to-ground stroke 

• Flash detection efficiency: Percentage of cloud-to-ground 

lightning flashes detected by the network 

• Stroke detection efficiency: Percentage of all return strokes 

within a flash detected by the network 


and several new sensor locations 

and relocations were planned to 

optimize network geometry. 

The combined magnetic direction 

finding and time-of-arrival 

sensing technology employed 

by each new IMPACT 

ESP sensor raises the benchmark 

for NLDN performance. This 

more advanced combined technology 

replaces the now outdated, 

stand-alone time-of-arrival 

technique and also updates the 

original IMPACT sensors. The 

IMPACT ESP – the third generation 

of the IMPACT sensor – 

has improved sensitivity, shorter 

dead time (less than 1 millisecond), 

and more processing power 

than its predecessor. Like earlier 

versions of the IMPACT 

sensor, the new sensor employs 

both electric and magnetic field 

sensing to provide both arrival 

time and azimuth information 

for each detected lightning discharge. 

A network of these new sensors 

can detect survey-level 

amounts of cloud lightning, depending 

on sensor spacing. This 

cloud lightning capability offers 

an important step toward more 

timely and more accurate nowcasting 

and forecasting since 

cloud lightning is a typical precursor 

to cloud-to-ground lightning 

as well as an indicator of 

heavy precipitation, downbursts, 

and other weather hazards. 

Cloud lightning is a valuable 

weather element used by aviation 

professionals, meteorologists, 

and others to issue thunderstorm 

warnings faster and 

more accurately by identifying 

thunderstorms earlier and providing 

more detailed storm information. 

Cloud lightning detection 

capabilities using either the IM- 

PACT ESP sensors or its 2004 

successor, the Vaisala Thunderstorm 

Total Lightning Sensor 

LS8000, is currently being evaluated. 

Preliminary Results 

Median stroke location accuracy 

of the NLDN is scientifically 

validated at 500 meters. The 

2002-2003 upgrade may have 

improved location accuracy in 

some regions, especially boundary 

areas, but location accuracy 

improvements are expected to 

be incremental and are currently 

undergoing re-validation. 

In 1998, flash detection efficiency 

was scientifically verified 

to range from 80 to 90 percent 

for those events with peak currents 

above five kiloamps, varying 

slightly by region. 

As of March 2004 the actual 

performance of the NLDN is 

still being confirmed by independent 

scientific evaluation, 

but preliminary evaluations and 

statistical models look promising. 

One evaluation project using 

digital video cameras with 

GPS time synchronization conducted 

by Kenneth E. Kehoe 

and University of Arizona professor 

E. Philip Krider around 

Tucson, Arizona – at a boundary 

of the network – during the summer 

of 2003 determined that average 

NLDN flash detection efficiency 

for 18 storms near Tucson 

was about 95 percent and stroke 

detection efficiency was about 

78 percent. A paper on this 

study is scheduled for presentation 

at the 18th International 

Lightning Detection Conference 

in June 2004. 

Observations in these other 

areas are also being evaluated: 

● Higher multiplicity 

● Detection of smaller median 

peak current 

● Lightning type classification 

for strokes below 10 to 20 

kiloamp range 

Significant Increase in 

Stroke Detection 

The most promising preliminary 

result thus far is the increase in 

stroke detection efficiency from 

40 to 50 percent in 1995 to 60 to 

80 percent today – an increase of 

20 to 30 percent. Evaluations indicate 

the upgraded network detects 

more small subsequent 

strokes. This increase in stroke 

detection efficiency ➤ 

NLDN Mission: 

Quality and Value 

The NLDN’s high standards 

of reliability, 

availability and performance 

are the result of 

well-planned redundancy 

and strict, documented 

quality control. NLDN operations 

are constantly scrutinized 

from data acquisition 

from the sensors to 

data delivery to customers. 

Here are a few highlights: 

Network Control Center for the 

NLDN and CLDN is manned 24 

hours a day, 7 days a week, 365 days 

a year. 

System-wide Redundancy 

• Two separate satellites and acquisition hubs acquire data 

from two evenly distributed sensor configurations. If one satellite, 

its hub, or its hub communication link fails, the sensor set 

reporting to the remaining satellite and hub provides sufficient 

coverage across the United States; 

• Private carrier-grade communications system of direct links 

with back-up links in the event of a primary circuit failure; 

• Two central processors operating independently with automatic 

fail-over for uninterrupted analyzes of incoming sensor 

data and lightning solution output; 

• Back-up network control center is available at State University 

of New York at Albany. 

Quality Control 

• NCC operators review regional network performance hourly 

using a graphical statistical analysis tool displayed by the central 

processor; 

• Comprehensive statistical reports on regional network performance 

and on individual sensor performance are generated 

by the central processor and reviewed daily by staff scientists; 

• Failure notification of any individual sensor occurs within one 

minute; 

• On-call repair and maintenance staff are dispatched to sensor 

sites usually within 48 hours of sensor failure and regional technicians 

can provide even more rapid response when needed. 

Uptime and Availability 

• 99.9789% average uptime for data acquisition from sensors 

(2003) 

• 99.9928% average availability of data broadcast to users via 

satellite (2003) 

• 99.9413% average availability of Internet services (2003) 

Mission Critical Operations 

• NCC is staffed 24 hours a day, 7 days a week, 365 days a year. 

• Controlled access to NCC. 

• Uninterrupted power supply with gas generator for sustainable 

power source to the NCC. 

• Disaster recovery procedure in place. ● 


leads to the increase in flash detection 

efficiency. 

Validation Results 

Forthcoming 

Video evaluation is underway 

near Dallas, Texas, which is considered 

to be an interior network 

location. In addition, detection 

efficiency, location accuracy, 

and peak current calibration 

studies are being carried out by 

researchers at the University of 

Florida's International Center 

for Lightning Research and Testing 

in Camp Blanding. Finally, 

relative detection efficiency 

measurements will be produced 

so that NLDN users will be able 

to compare 2002 and later lightning 

information with previous 

years. 

Like validation studies after 

the 1994-1995 upgrade, final 

evaluation results from the GPSsynched 

digital video evaluations 

and relative detection efficiency 

analysis of the 2002-2003 

upgrade will be made available 

to NLDN users as they become 

available. ● 

Key Applications for NLDN Lightning Data 

• Weather forecasting: Help predict severe weather for public warning 

• Electric power utilities: Pre-position field crews for approaching storm threats and to improve 

engineering and design with lightning analysis 

• Air traffic management: Re-route aircraft around hazardous thunderstorms 

• Airports: Suspend high-risk activities like fueling during lightning threats 

• Insurance and arson: Investigate lightning as the cause of property damage or fire 

• Power-sensitive operations: Prepare for storm-caused power outages by switching to back-up 

power early 

• Hazardous materials handling: Warn personnel working near explosives and flammable 

materials to evacuate 

• Forestry: Dispatch crews to suspected fire starts for more successful initial attack 

• Golf and outdoor recreation: Warn players to seek safety from storms 

• Aerospace: Monitor for safest weather conditions for shuttle and satellite launches 

Comparison: Before and After the 2002-2003 NLDN Upgrade 

Basic Parameters Before After* 

Number of sensors 107 113 

Types of lightning sensors First generation IMPACT sensors Third generation Vaisala 

and older LPATS III sensors 

IMPACT ESP sensors 

Sensing technology Combined MDF/TOA sensors Combined MDF/TOA sensors 

and TOA only sensors 

Flash detection efficiency 80-90% 90% or better 

Stroke detection efficiency 40-50% 60-80% 

Stroke location accuracy 500-meter median error 500-meter median error 

Network uptime > 99.7% > 99.7% 

Minimum peak current detected 

(1st percentile) As low as 5-8 kA As low as 3-4 kA 

Multiplicity 1.9 to 2.4, varying by region Increased by 20-30% 

*Independent validation studies were still underway in March 2004 

to verify these preliminary findings 


Nicholas W. S. Demetriades, 

Research Scientist 

Ronald L. Holle, 

Meteorologist/Consultant 


Tucson, USA 

Exploring 

Long-Range Lightning Detection 

over the Oceans 

Vaisala's Research in transoceanic lightning tracking points to more 

accurate prediction models and improved aviation and maritime 

transportation safety. Vaisala and its research partners are studying 

cloud-to-ground lightning tracking techniques, effectiveness, and 

applications with experimental versions of Vaisala IMPACT ESP 

Lightning Sensors that use very low frequency (VLF) lightning 

detection technology. 

Long-range lightning data 

over ocean areas looks especially 

promising for 

more accurate numerical weather 

prediction models and storm 

forecasts for densely populated 

coastal areas. It also improves 

weather observations where undetected 

hazardous weather impacts 

aviation and shipping 

transportation routes and safety. 

Lightning Adds 

New Dimension 

Oceanic weather observations 

are collected primarily from 

these sources: 

● Surface weather observation 

stations aboard ships and 

buoys 

● Aircraft 

● Geostationary and polarorbiting 

satellites 

● Upper air soundings from 

islands 

The quality of these observation 

methods continues to be 

improved and refined, but the 

data quantity and type have not 

changed substantially. Using 

these data sources, numerical 

weather prediction forecasts of 

oceanic storm positions can still 

be off by hundreds of kilometers, 

resulting in adverse impacts 

to coastal communities. 

Preliminary long-range lightning 

observations and research 

models over the Pacific and Atlantic 

Oceans and Gulf of Mexico 

suggest that lightning mapping 

may be able to improve 

oceanic storm location accuracy 

and therefore significantly reduce 

forecast errors. 

Transportation 

Routes and Safety 

Ships and aircraft face severe 

weather hazards that threaten 

human safety and can result in 

damage or loss of goods being 

transported. By knowing where 

and when convective weather is 

active, dispatchers and air traffic 

management can modify routes 

to avoid thunderstorm hazards. 

As it does over land masses, 

lightning enables faster and 

more accurate identification of 

convective weather. Since ➤ 


Kathryn Schlichting 

Marketing Manager 


Sunnyvale, USA 

radar is not available over the 

oceans, lightning data is even 

more important for accurate 

identification of formation and 

dissipation of convective cells. 

Satellite imagery is available 

over the oceans, but does not 

provide the level of detail and 

timeliness that lightning data 

can provide. Satellite imagery is 

often of limited use for identifying 

convective activity when obscured 

by higher clouds. 

Pacific Ocean 

Research 

For lightning activity mapping 

over the north and central Pacific 

Ocean areas, experimental longrange 

VLF lightning sensors – 

modified versions of Vaisala IM- 

PACT ESP Lightning 

Sensors – were installed 

on the islands 

of Kaui and Kona, 

Hawaii and Dutch 

Harbor, Alaska. 

Data from these 

lightning sensors is 

supplemented with 

data from Pacific 

Coast-area sensors 

from Vaisala’s U.S. 

National Lightning 

Detection Network 

and Environment 

Canada’s Canadian 


Network. 

Figure 1 shows 

five consecutive days 

of lightning activity 

over the North Pacific 

Ocean. Figure 2 illustrates 

how adding 

lightning to satellite 

imagery provides 

valuable detail about 

the convective areas 

of a cold front. 

Important 

Benefits 

Anticipated 

Research and development 

will continue 

in long-range cloudto-ground 

lightning 

detection and applications. 

Early obser- 

Vaisala is privileged to collaborate on 

long-range lightning applications with research teams from 

these distinguished organizations: 

● Aviation Weather Center of the National Weather Service 

● University of Hawaii School of Ocean & Earth Science & Technology 

and associated collaborators 

● NASA’s Marshall Space Flight Center 

● National Weather Service Forecast Offices in Seattle, Jacksonville, 

and Upton 

● University of Washington, Department of Atmospheric Sciences 

● State University of New York at Stony Brook Department of Atmospheric 

Sciences 

● Environment Canada 

Figure 1. More than 10,000 cloud-to-ground lightning strokes were detected over the 

North Pacific Ocean over a 120-hour period starting 00h00 UTC on 10 February and 

ending at 24h00 UTC on 14 February 2004. 

PHOTOCOURTESY OF NOAA/NWS. 

vations point to very exciting advances 

that extend the reach of 

lightning observations to areas 

where better identification of developing 

weather patterns and 

hazardous convective weather are 

needed to improve weather forecasts. 

● 

Figure 2. Satellite imagery and 

long-range cloud-to-ground 

lightning detected between 1421 

and 1721 UTC 18 December 

2002 over the North Pacific. 

Flashes indicate convection along 

a cold front, in the cold pool 

behind the front, and ahead of 

the frontal system. The presence 

of lightning indicates convection 

in only a portion of the locations 

with high clouds shown by 

infrared satellite imagery. 

New Vaisala products 

introduced at AMS 

The AMS meeting is the host to 

the largest exhibit program anywhere 

in the atmospheric, 

oceanic and related sciences. It 

provides the best showcase for 

introducting new and innovative 

equipment in these industries. 

Vaisala had a number of products 

which launched at the AMS 

meeting including: 

● Vaisala Thunderstorm Information 

System, the integrated 

technology lightning sytem 

● Vaisala Ceilometer CL31 

● Vaisala CARBOCAP ® Carbon 

Dioxide Probe GMP343 

● Vaisala TacMet Tactical 

Meteorological Observing System 

MAWS201MP, the pole 

mounted sytem 

● Vaisala Software Defined 

Receiver/Processor, SPS311, for 

use in the Vaisala DigiCORA ® 

● New Vaisala DigiCORA ® 

Tethersonde features including 

balloon improvements for increased 

flight stability, and safety, 

as well as many software improvements 

and upgrades. 

Other Vaisala products of 

keen interest to visitors to the 

booth were the Vaisala Radiosonde 

RS92, Vaisala Incident 

Weather Observing Station 

IWOS, Vaisala Wind Profilers 

and Vaisala Ultrasonic Wind 

Sensor. 

Our booth was active with 

many AMS attendees stopping 

by to see our product offerings 

and talking with Vaisala personnel. 

First ever 

Vaisala workshop 

Vaisala held its first workshop at 

AMS and featured product presentations 

by the Soundings, 

Wind Profiler, and Thunderstorm 

groups. The four-hour 

workshop was a venue where 

Vaisala's new products and upgrades 

could be discussed in detail 

with a group of interested 

customers. Ken Goss, Director 

of Sales and Marketing for 

North America was extremely 


Vaisala takes part in the 84 th 

American Meteorological Society 

Annual Meeting in Seattle 

The 84 th American Meteorological Society (AMS) Annual Meeting was held January 11-15 

in Seattle, Washington. Vaisala was an active participant on many fronts including the exhibition, 

presentation of papers, the general public WeatherFest forum, hosting a workshop, 

and meeting with customers in all areas of our meteorological business – soundings, aviation 

weather, wind profilers, hydrometeorology, thunderstorm detection and data systems, 

optical sensors and instrumentation. The AMS meeting was a resounding success. 

to the general public called 

WeatherFest. This interactive 

half-day science and weather fair 

is designed to promote the field 

of meteorology to students, elementary 

and secondary school 

teachers, media, and weather 

hobbyists of all ages. Educational 

materials were provided on 

the Vaisala U.S. National Lightning 

Detection Network and 

lightning safety at the Weather- 

Fest fair. 

George Frederick, Del Hildebrand and Geoff Bing in the Vaisala Remote Sensing section of the Vaisala Booth. 

pleased with the participation 

and outcome of the event. 

“Vaisala’s first AMS workshop 

was a resounding success for customers 

from a number of application 

areas. In a fast paced series 

of presentations, Vaisala 

brought them up to speed on 

our latest product offerings”, 

noted Ken. The event was very 

well received with many important 

customers in attendence 

participating in productive 

group discussions. 

Vaisala presents 

six technical papers 

Research and Development (R & 

D) is an area in which Vaisala is 

constantly investing. We presented 

selected topics at AMS as 

our way of offering the newest in 

technological advances to the 

meteorological field. Six papers 

were presented by Vaisala R & D 

personnel from our Optical, 

Thunderstorm, Wind Profiler, 

and Soundings groups. These 

papers were published by AMS 

and distributed to everyone attending 

the conference sessions. 

Involving 

the general public 

This year Vaisala participated in 

the pre-conference event open 

Seattle offered 

good surroundings for 

AMS 2004 

Overall, the AMS Annual Meeting 

attracted more then 3,400 attendees 

to 21 conferences and 

symposia as well as various 

workshops and courses. The 

WeatherFest, an educational 

event open to the public and the 

media, attracted over 1,000 people. 

Everyone enjoyed the venue 

with downtown Seattle offering 

its gourmet coffee, fresh salmon 

and seafood, lively Pike Place 

Market, and plenty of rain. 

The 2005 AMS Annual 

Meeting to be held 9-13 January 

in San Diego, California will 

have the conference theme, 

“Building the Earth Information 

System”. It will provide another 

opportunity for Vaisala to showcase 

its leadership in weather observation 

systems and instrumentation. 

● 


Maria Rita Leccese 

Managing Director 

Eurelettronica Icas Srl 

Rome, Italy 

Vaisala Radiosonde RS92: 

On Trial in Italy 


The Vaisala Radiosonde RS92 family has been available for over a year 

along with the supporting Vaisala DigiCORA ® Sounding System and 

sounding software. Worldwide, a number of RS92 operational trials 

have been concluded successfully. A greater number are either 

underway or scheduled to begin soon. This article focuses on the RS92 

trial that was conducted in Italy by Vaisala in collaboration with the 

Italian Air Force and Reparto Sperimentazioni di Meteorologia 

Aeronautica (ReSMA), the Center for Air Force Meteorological Research. 

The “Italian Air Force trial” 

was conducted in two 

test phases. The first 

phase took place in mid-November 

2003, the second in early 

March 2004. The Italian Air 

Force trial compared the measurement 

performance of the alldigital 

RS92-SGP to that of the 

RS90-AG, complete with their 

respective ground equipment 

and sounding software. Every dimension 

of radiosonde performance 

was analyzed. Special attention 

was paid to ensuring the 

continuity of aerological data 

when making the operational 

transition from the RS90 to the 

RS92. 

The first Vaisala Radiosonde RS92-SGP/RS90-AG test rig is launched at Vigna di 

Valle, witnessed by General Roberto Sorani, chief of the UGM. 

Italian Air Force 

Meteorological Service: 

some background 

The Italian Air Force has run a 

Meteorological Service since 

1925. This service assumed a 

central role of national importance 

in 1950, when Italy joined 

the WMO. Over the years, the 

Italian Air Force Meteorological 

Service has built an extensive 

observation network which covers 

the national territory. Nowadays 

the Italian Air Force Meteorological 

Service acts as the national 

weather service, responsible 

for general weather forecasting, 

issuing weather bulletins 

and alerts for public safety. The 


Service runs 6 synoptic sounding 

stations located in Milano 

Linate, Udine Campoformido, 

Pratica di Mare, Cagliare Elmas, 

Brindisi and Trapani Birgi. 

The Italian Air Force Meteorological 

Service also carries 

out climatological and environmental 

analyzes in growing cooperation 

with the Regional 

Meteorological Services, which 

were formed to support local socio-economic 

activities by providing 

high-resolution, localized 

meteorological products. The 


Service is managed by Ufficio 

Generale per la Meteorologia 

(UGM), formed within the “Comando 

Squadra Aerea” with its 

headquarters in Rome. 

Reparto 

Sperimentazioni di 

Meteorologia 

Aeronautica (ReSMA) 

The Reparto Sperimentazioni di 

Meteorologia Aeronautica (ReS- 

MA) is the Center for Air Force 

Meteorological Research. Its responsibilities 

include overseeing 

the quality of meteorological observations, 

certifying the compliance 

of weather instruments to 

international standards and conducting 

special weather observation 

campaigns. 

Role of the Italian 

Space Agency in 

the trial 

Vaisala has developed a close relationship 

with the Italian meteorological 

research community 

over the years, in particular with 

the Agenzia Spaziale Italiana 

(ASI ), the Italian Space Agency. 

ASI’s base in Trapani Milo has 

been a very active contributor to 

many European atmospher- ➤ 


The Reparto Sperimentazioni di 

Meteorologia Aeronautica 

(ReSMA) research station in Vigna 

di Valle. 

ic research programs thanks to 

its ideal location, modern instrumentation 

and highly trained 

staff. For these and other reasons, 

Vaisala came up with the 

idea of using the Trapani Milo 

base for initial operational testing 

of the RS92 in Italy. Vaisala 

approached ASI with the idea, 

the ASI kindly agreed, and RS92 

operational tests were carried 

out in June 2002 and late September 

2003. 

The encouraging results of 

the Trapani Milo test were the 

background to the Italian Air 

Force operational trial, which included 

tests at ReSMA’s Vigna di 

Valle sounding station from 7-20 

November 2003 and at the Trapani 

Birgi sounding station from 

8-10 March 2004. 

Goals of the Italian 

Air Force trial 

The primary goal of the Italian 

Air Force trial was to compare 

the pressure, temperature and 

humidity (PTU) measurement 

performance of the Vaisala Radiosonde 

RS92-SGP to that of 

the RS90-AG currently used at 

Air Force sounding stations, as 

well as to assess the improved 

windfinding performance 

brought by Vaisala’s new codecorrelating 

GPS technology. The 

secondary goal was to evaluate 

the benefits of upgrading to the 

Vaisala DigiCORA Sounding 

System MW21 from the Vaisala 

MARWIN ® Sounding System 

MW12 and Vaisala DigiCORA 

Sounding System MW11/15 

systems currently in use. The Air 

Force testers directly compared 

the general usability of the 

MW21 and MW12 systems in 

light of their respective ground 

check procedures, reading of calibration 

coefficients and adjustment 

of transmitter frequencies. 

Phase 1, 

Vigna di Valle test 

Phase 1 of the Italian Air Force 

trial comprised 15 soundings 

made at the Vigna di Valle research 

station. Ten of the soundings 

were twin soundings of the 

RS92-SGP/RS90-AG; five were 

solo soundings. The majority of 

the twin and solo soundings 

were made at the standard synoptic 

times of 6:00, 12:00 and 

18:00. The Vigna di Valle weather 

station often experiences radar 

interference from a nearby radar 

installation, which was an illuminating 

factor in the testing. 

Phase 2, 

Trapani Birgi test 

Phase 2 of the Italian Air Force 

trial comprised 7 soundings 

made at the Trapani Birgi sounding 

station, at the standard synoptic 

times of 12:00, 18:00 and 

24:00 and hours in-between. 

Like Vigna di Valle, the Trapani 

Birgi sounding station often experiences 

radar interference 

from a nearby radar installation. 

Radiosonde set-up at 

Vigna di Valle 

Ten twin soundings of the Vaisala 

Radiosonde RS92-SGP/RS90-AG 

were made at Vigna di Valle. At 

launch, the radiosondes were suspended 

about 1 meter below the 

test rig. After launch and unwinding, 

the radiosondes reached a suspension 

point approximately 60 

meters below the sounding balloon. 

The same was true for the 5 

solo soundings that were made: 

four RS92-SGP soundings and 

one RS90-AG sounding. 

Radiosonde set-up at 

Trapani Birgi 

Seven soundings were made at 

Trapani Birgi. The radiosonde 

set-up was slightly different than 

the one used at Vigna di Valle. 

Trapani Birgi is a synoptic 

sounding station and the soundings 

were done so as not to disturb 

normal operation. The 

RS92-SGP and RS90-AG were 

not placed on a rig but launched 

separately and simultaneously. 

Ground equipment 

set-up 

Two sounding systems were used 

to collect data from the two radiosondes. 

ReSMA’s existing 

Vaisala MARWIN Sounding 

System MW12 system was used 

to receive data from the RS90- 

AG. A newly installed Vaisala 

DigiCORA Sounding System 

MW21 was used to receive data 

from the RS92-SGP. 

At Trapani Birgi the existing 


System MW15 system was used 

to receive data from the RS90- 

AG. A Vaisala DigiCORA ® 

Sounding System MW21 was 

used to receive data from the 

RS92-SGP. Both sounding systems 

were operated independently, 

in normal mode. The RS90- 

AG ground check was carried out 

as normal with the GC24 ground 

check set. The RS92-SGP ground 

check was carried out as normal 

with the Vaisala Ground Check 

Set GC25. 


Italian Air Force testers with a Vaisala Radiosonde RS92- 

SGP/RS90-AG test rig ready for launch. 

Figure 1. Vaisala Radiosonde RS80-15GE/RS92-SGP twin sounding: RS80- 

15GE humidity measurement in red, RS92-SGP humidity measurement in blue 

Data collection 

and processing 

RS90-AG data was collected 

from the Vaisala MARWIN 

Sounding System with a separate 

PC, loaded with Vaisala Metgraph 

software. The edited 

(EDT) data generated by the 


System MW21 system was extracted 

from the MW21’s sounding 

database after every sounding 

– a useful ability made possible 

by the new system architecture. 

The EDT data, generated every 

two seconds, was analyzed using 

the new RSK32 software developed 

by Mr. Sergei Kurnosenko. 

Vaisala Radiosonde 

RS92 vs. RS90 PTU 

performance 

PTU data availability 

The raw PTU data received by 

the MW21 and MW12 sounding 

systems was used to calculate 

the average availability of PTU 

data for the RS92-SGP and 

RS90-AG, as shown below: 

P T U 

RS92-SG 98.6% 97.5% 99.3% 

RS90-AG 86.7% 92.0% 92.6% 

Relative humidity 

The RS92 and RS90 measure relative 

humidity with similar performance 

– the same humidity 

sensor is used for both radiosondes. 

This humidity sensor is 

made of an H-type polymer, 

which is a significant technological 

advance over the A-type 

polymer used in the manufacture 

of humidity sensors for 

RS80 radiosondes. 

Moreover, the RS90 and 

RS92 are equipped with two H- 

type humidity sensors and a technique 

which alternately heats 

them. When one H-type humidity 

sensor is measuring, its twin is 

off-line and heated to prevent icing 

in preparation for coming online. 

When the RS92 ascends 

through clouds at low altitudes, 

therefore, its humidity measurements 

are unaffected by icing. 

Furthermore, when the RS92 

emerges from low-lying cloud, its 

humidity measurements are 

largely unaffected by the transition 

from the cloud’s high-humidity 

conditions to “normal” atmospheric 

conditions. 

Spotlight: Vaisala Radiosonde RS92-SGP 

vs. RS80-15GE humidity measurement 

O 

ne 

RS92-SGP/RS80-15GE twin sounding was made to compare 

the humidity measurement performance of these 

two radiosondes (see Figure 1 above). A single sounding is not 

statistically significant. That said, the result reinforced the experience 

of recent WMO intercomparisons, which have shown that 

the RS92’s humidity sensor has a faster response time than the 

RS80’s humidity sensor and has a better temperature dependence 

correction, especially at cold temperatures (below -40 °C). 

This is clearly seen in the 8 – 14 km altitude range of Figure 1. At 

an altitude of approximately 11 km, the RS92-SGP/RS80-15GE rig 

entered a cloud and the humidity measurements of the two radiosondes 

suddenly diverge widely. ● 


RS92-SGP vs. RS90-AG 

humidity measurement 

The eight RS92-SGP/RS90-AG 

twin soundings carried out at Vigna 

di Valle were used to generate 

statistics on the direct differences 

in humidity measurement 

between the two radiosondes. As 

seen in Figure 2, the average direct 

difference was less than 3%. 

A factor which contributed 

significantly to the difference 

was the improved ground check 

procedure for the RS92. This 

procedure takes advantage of the 

new reconditioning functionality 

in the Vaisala Ground Check 

Set GC25. The reconditioning 

of the RS92’s twin humidity sensors 

eliminates any chemical 

contamination that may have 

occurred during storage to throw 

off humidity measurement during 

sounding. 

As seen in Figure 2, the 

RS92-SGP was used as the reference 

and measured higher humidity 

values than the RS90-AG 

at low altitudes (0-8 km) thanks 

to its reconditioned humidity 

sensors. The difference at higher 

altitudes is due to the slightly improved 

temperature dependence 

correction used for the RS92- 

SGP. In general, Figure 2 shows 

good correlation in humidity 

measurement between the RS92- 

SGP and RS90-AG, but a slight 

edge in performance must be 

given to the RS92-SGP. ➤ 


were compared to an external 

reference. The correction values 

were fed into the MW21 sounding 

system. Also following normal 

procedure, the RS90-AG 

was not pressure-corrected. Figure 

3 shows the result: very minor 

differences between the 

pressure measurements of the 

two radiosondes at very low altitudes, 

and increasingly good 

correlation as higher altitudes 

are reached. 

Figure 2. 1 Average direct differences in humidity measurement, Vaisala Radiosonde RS90-AG vs RS92-SGP. 

The bold blue line in the middle shows the humidity values measured by the RS92-SGP used as the reference. 

The RS90-AG is the bold red line. 

Figure 3. 2 Average direct differences in pressure measurement, Vaisala Radiosonde RS90-AG vs RS92-SGP. 

The bold blue line in the middle shows the pressure values measured by the RS92-SGP, used as the reference. 

The RS90-AG is the bold red line. 



pressure measurement 


twin soundings of the Vigna di 

Valle test were used to compare 

the direct differences in pressure 

measurement between the two 

radiosondes. The RS92-SGP was 

pressure-corrected following 

normal procedure: the RS92- 

SGP’s pressure measurements 



temperature 

measurement 


twin soundings of the Vigna di 

Valle test were used to compare 

the direct differences in temperature 

measurement between the 

two radiosondes. 

An improved temperature 

dependency correction has 

been developed for the RS92 

temperature sensor. The results 

of this improvement are seen in 

Figure 4. 



wind data availability 

The RS92-SGP’s code correlating 

GPS (ccGPS) technology enables 

highly accurate calculations 

of wind speed and direction 

and provides continuous 

wind data availability. The new 

ccGPS technology also features 

a high signal-to-noise ratio and 

immunity to non-GPS signals. 

Average wind data availability 

for the RS92-SGP as received 

by the MW21 sounding system 

was found to be 94.4% at Vigna 

di Valle and 95.5% at Trapani 

Birgi, based on calculations 

made with the raw GPS information 

received by the ground 

equipment. Average wind data 

availability for the RS90-AG as 

received by the MW12 sounding 

system was found to be 23.3%. 

Given that both test sites 

regularly experience strong external 

interference on the GPS 

band, the wind data availability 

figures for the RS92-SGP were 

considered to be very good. As 

the wind data availability figure 

of 23.3% shows, the RS90-AG is 

far more sensitive to radar interference 

than the RS92-SGP. 


Figure 4. 3 Average direct differences in temperature measurement, RS90-AG vs RS92-SGP. The bold blue line on the 

right shows the temperature values measured by the RS92-SGP, used as the reference. The RS90-AG is the bold red line. 

Handling the Vaisala 

Radiosonde RS92-SGP 

and RS90-AG on 

the ground 

The Air Force testers compared 

the general usability of the 

Vaisala MARWIN Sounding 

System MW12/DigiCORA 

MW15 and Vaisala DigiCORA 

Sounding System MW21 in 

light of the respective ground 

check procedures, the reading of 

calibration coefficients and the 

adjustment of transmitter frequencies. 

The Air Force testers discovered 

that the GC25 simplifies 

the ground check procedure – it 

reads calibration coefficients automatically, 

for example. They 

also found that the RS92-SGP is 

easier to handle than the RS90- 

AG. It is easier to take out of its 

package and assemble, easier to 

ground-check, and easier to 

launch thanks to its small size 

and simple, single-phase unwinder. 

The Air Force testers also 

noted the GC25’s humidity sensor 

reconditioning functionality 

and the benefit it provides: it improves 

the accuracy of humidity 

measurement by removing substances 

which may have contaminated 

the humidity sensors during 

storage or shipping. 

The Air Force testers also 

noted how easy it was to adjust 

the RS92-SGP’s transmitter frequency 

with the GC25. As a 

general conclusion, they found 

the GC25 to be an improvement 

over older Vaisala ground check 

sets such as the GC24. 

Conclusions 

Like every national meteorological 

service, the Italian Air Force 

Meteorological Service takes 

great care to ensure the continuity 

of aerological data when 

adopting a new radiosonde for 

its upper-air program. 

Since the RS92 and RS90 radiosondes 

share the same PTU 

sensors, the Air Force testers did 

not expect to see significant differences 

in PTU measurement 

performance between the two radiosondes. 

This was not taken 

for granted, however, since the 

two radiosondes are different in 

size, weight and construction. 

The Italian Air Force trial was set 

up carefully to ensure that any 

differences in performance were 

indeed identified and analyzed. 

The similarities and differences 

that were found in the trial 

can be summed up in the following 

general conclusions: 

● The differences that were 

seen in temperature measurement 

were attributable to the 

slightly different temperature dependency 

corrections used for 

the RS92-SGP and RS90-AG. 

The RS92’s temperature dependency 

correction is an improvement 

over the one used for the 

RS90. 


seen in humidity measurement 

were attributable to the RS92 

humidity sensor reconditioning 

and the RS92’s improved temperature 

dependency correction. 

Done as part of the ground 

check, the reconditioning solves 

the so-called "dry bias" problem 

of humidity measurement. 


seen in pressure measurement 

were attributable to the fact that 

a ground reference pressure correction 

was applied to the 

MW21 used with the RS92-SGP, 

but not to the MW12 used with 

the RS90-AG. 


seen in wind data availability 

were attributable to the fact that 

codeless GPS technology is used 

with the RS90-AG and correlating 

GPS technology is used with 

the RS92-SGP. The presence of 

external interference in the GPS 

band made the differences very 

substantial. Wind data availability 

with the RS92-SGP is significantly 

higher than with the 

RS90-AG. The RS92-SGP’s alldigital 

data transmission was also 

a contributing factor. 

At the conclusion of the Italian 

Air Force trial, the Air Force 

testers welcomed the performance 

of the Vaisala Radiosonde 

RS92 for operational 

use in their upper-air program. 

Vaisala appreciates the spirit 

of cooperation that characterized 

the Italian Air Force trial. 

We send a special thank-you to 

Col. Giovanni Casu (Chief of 

ReSMA) and his personnel; 

Cap. Orazio Di Casola, M.llo 

Luigi Peloso and their personnel 

in Trapani; M.llo Claudio Esposito 

and Stefano Rocchetti 

from the 8°RTO maintenance 

group of Pratica di Mare. ● 

Footnotes 

1 This Figure is based on the twin 

soundings made at Vigna di Valle. 

Each sounding generated approximately 

3,000 rows of data. The differences 

seen in this Figure are 100% direct 

differences. 






differences. 






differences. 




Helsinki, Finland 

Chilean Navy Weather Service 

Invests in Vaisala Automatic 

Weather Stations 

The Chilean Navy Weather Service has undertaken a 10-year METEO 

project to improve the reliability and accuracy of coastal weather 

information and has selected Vaisala Automatic Weather Station 

MAWS301 to meet their goals. The objective of the project is to 

improve the safety at sea by spreading more current information to 

ships along the Chilean coast. 

Over the course of 2003 

the Chilean Navy 

Weather Service (CN- 

WS) decided to launch a 10-year 

project called METEO. An integral 

part of this project is the installation 

of Vaisala Automatic 

Weather Station MAWS301 in 

20 existing Coastal Synoptic Stations 

as well as 20 new observation 

stations to be set-up along 

the coast. The MAWS301 station 

is equipped with sensors to 

measure wind velocity and direction 

(WAS425S), air pressure 

(PMT16A), and temperature, relative 

humidity, and precipitation 

(QMR102). The investment 

in the top of the line MAWS301 

will help improve the reliability 

and accuracy of the data being 

collected from the various 

weather stations along the 

Chilean coastline. 

Making measurements 

in remote and difficult 

to access areas easy 

The Vaisala Automatic Weather 

Station MAWS301 is a new generation 

automatic weather station 

especially designed for applications 

where no commerical 

power or communication networks 

are present or are too expensive 

to be installed. The 

MAWS301 is a very flexible system 

which can be used for both 

hydrological and meteorological 

applications. Based on the latest 

technology both in measurements 

and communication, the 

MAWS301 can be interfaced 

with a multitude of telecommunication 

equipment such as standard 

PTSN and GSM modems, 

radio modem and satellite transmitters. 

The MAWS301 can 

even be connected directly to a 

LAN network via TCP/IP using 

standard COM Server devices. 

The Vaisala MAWS301 has 

been designed for applications 

where only a few sensors are required. 

The system can however, 

easily be upgraded, even in the 

field, to include a larger set of 

sensors, including smart sensors 

such as a ceilometer, visibility 

and present weather sensors and 

water quality probes. 

All of these functionalities 

made the MAWS301 particularly 

well suited for the Chilean 

coastal conditions as many of the 

existing and planned coastal synoptic 

stations are located in remote 

and difficult to access areas. 

Personnel and equipment has to 

be transported to the stations 

across fjords, channels, valleys 

and forests by use of helicopters, 

navy vessels or small boats. 

Accurate and 

reliable data improves 

the safety at sea 

Safety at sea requires accurate, 

real-time information. The CN- 

WS is responsible for monitoring 

weather conditions in the 

coastal areas of Chile, and for issuing 

bulletins and warnings 

about adverse conditions. Lighthouse 

personnel compile a Maritime 

Weather Forecast Analysis, 

which is broadcast through the 

Coastal Radio Network. The data 

collected by the new 

MAWS301 system, combined 

with existing, conventional 

equipment will greatly improve 

the accuracy of these reports, 

and the safety of vessels operating 

in Chilean waters. 

Vaisala: a complete 

service provider 

Vaisala, through its local representative 

in Chile, Metcom Limitada 

is providing the CNWS 

with technical support, assistance 

with installation and operation 

of the MAWS301, as well as operational 

training to the CNWS 

personnel. This arrangement of 

providing support services locally 

has lead to the successful first 

phase of this 10-year project. ● 


Ritva Siikamäki, MA 


The tests were conducted 

at a 500kV transmission 

line called President Dutra 

- Terezina II, in Maranhão 

State in Brazil. Mr. Sebastião 

José Gusmão Cavalcanti, the former 

CHESF transmission line 

designer, who acted as a consultant 

on the project, specified and 

installed a pair of Vaisala Automatic 

Weather Station 

MAWS101 on top of several 

towers on the site. He comments 

that this was the most trustworthy 

and efficient weather station 

he has ever worked with, after 

twenty years of experience with 

close to a dozen different types 

of instruments for this use. Although 

not using all the capabilities 

the system offers, the versatility 

of data acquisition modes 

on this instrument allowed him 

calculations, that were both precise 

and adequate for many purposes 

such as wind gusts or aeolic 

effects on towers, cables, insulation 

distances, pollution 

spreading, etc. 

The main objective was to assess 

the suitability and performance 

of the MAWS101 for 

monitoring overhead power 

transmission lines which are subject 

to all types of weather, including 

high winds. The wind information 

provided by the 

MAWS101 was used to monitor 

the performance of vibration 

dumpers. The MAWS101 is also 

being used to increase knowledge 

on the swinging and clashing 

risks of cables in huge bundles 

without spacers. Brazil has 

pioneered the so-called “Expanded 

Bundle – FEX”, cables which 

are 1.4 meters apart, developed 

for high transmission lines. This 

new technology allows for the 

Vaisala Automatic Weather Stations MAWS101 

Monitoring 

Transmission Lines 

In Brazil, Companhia Elétrica do Vale do São 

Francisco (CHESF), which provides electricity to eight 

North-Eastern States, has introduced the use of 

Vaisala Automatic Weather Stations MAWS101 atop 

overhead transmission line towers. The anemographs 

based on the data from the MAWS101 have been 

produced for more than one year and have proven 

useful in this application. 

adjustment of electrical parameters 

to increase power transmission 

by 25% without any additional 

costs. Further intended 

purposes of wind anemographs 

on transmission lines are to 

monitor the thermal dissipation 

conductors for Ampacity studies, 

i.e. to follow up the capacity of 

power transport of the line upgradings. 

Moreover, the data on 

wind gusts is used for monitoring 

the mechanical loadings of 

the structures. 

Vaisala wind sensors on a transmission line of 

Companhia Hidro Elétrica do São Francisco. 

Some of the test findings 

were presented in October 2003 

at the national seminar on production 

and transmission of 

electricity (SNPTEE) sponsored 

by CIGRÉ in Uberlândia, 

Brazil. The paper (ref. IT-GLT- 

024) presented examples of 

monitoring performed in the pioneer 

expanded bundle 230kV 

and 500kV transmission lines. 

Its main conclusion is to recommend 

the creation of a working 

group in CIGRÉ CE22 for the 

systematization of mechanical 

data acquisition and apply the 

procedures in the different types 

of transmission lines, environments 

and hardware in which 

risk expectations may suggest 

the need for historical observation. 

The Technical Report also 

outlines the updating of monitoring 

technology and instruments 

for predictive maintenance 

of both conventional and 

new expanded bundle transmission 

lines. ● 

The processor unit of the Vaisala Automatic Weather 

Station MAWS101 on a power pylon. 


Maria Rita Leccese 

Managing Director 

Eurelettronica Icas Srl 

Rome, Italy 

Vaisala Automatic Weather Station MAWS301 

Update of the Hydrometeorological 

Real-Time Network in 

North-Eastern Italy 

Since the mid 1980’s Regione 

Emilia Romagna 

has been active 

in the provision of regional 

weather forecasts. The existing 

hydro-meteorological real-time 

network employs several technologies, 

ranging from Surface 

Weather Stations to Weather 

Radars and Radiosounding system. 

After several organizational 

changes over the years, the dedicated 

organization is today the 

Regional Hydro-Meteorological 

Service (SIM). SIM operates 

within the Regional Agency for 

Environment Protection (Agenzia 

Regionale Protezione Ambiente 

–ARPA). The ARPA SIM 

headquarter and the Chief Prof. 

Stefao Tibaldi are located in 

Bologna and it is from there that 

the networks of automatic 

weather stations, the weather 

radars and the automatic radiosounding 

system are remotely 

managed. 

ARPA SIM has defined its 

mission as to: 

● Manage networks of automatic 

weather stations and collect 

data in real time from the 

GTS network 

● Process and distribute 

“short notice” weather forecasts, 

on a high resolution local scale 

and different time schedules 

● Distribute, to a diversified 

number of users, specialized 

weather products (i.e. Teleneve 

and Icecast-Forecaster) 

● Carry out climatological 

data processing to support studies 

of climatic changes on the regional 

level 

Tender requirements 

and award 

In the late summer of 2003, 

ARPA Emilia Romagna issued a 

call for tenders for the turn-key 

supply of 49 automatic weather 

stations, to upgrade and expand 

one of the existing surface observation 

networks. The automatic 

weather stations were divided into 

two types: 9 urban (configured 

to measure air temperature 

and humidity, wind speed and 

direction, rain and net solar radiation) 

and 40 agrometeorological 

stations (with different configurations 

to measure, depending 

upon the setup, air temperature 

and humidity, wind speed 

and direction, rain, globan solar 

radiation and leaf wetness). All 

49 automatic weather stations 

were specified in the tender with 

enhanced characteristics such as 

full data logging configuration, 

GSM/GPRS data link and solar 

panel powering. 

In the tender it was stated 

that the contract would be 

awarded to the supplier able to 

offer the best equipment based 

on an evaluation of the price and 

technical specifications. In order 

to propose the most competitive 

offer in terms of a technical, logistical 

and pricing solution, 

Vaisala Hydromet bid the tender, 

as Prime, in co-operation 

with the Vaisala's long-time Italian 

representative, Eurelettronica 

Icas Srl. 

In December 2003, as a result 

of the tender award, Vaisala 

HydroMet signed a contract with 

ARPA Emilia Romagna marking 

the introduction of the Vaisala 

Automatic Weather Station 

MAWS301 to the Italian market. 

The MAWS301 features state-ofthe 

art technology for automatic 

weather stations in terms of sensor 

configuration, telecommunication 

and power supply. 

Specifications and 

installation of 

the Vaisala Automatic 

Weather Station 

MAWS301 

The installations started in the 

early spring of 2004 in Piacenza, 

Parma, Reggio Emilia, Modena, 

Ferrara, Ravenna, Forlì, Cesena 

and Rimini all urban sites, with 

beautiful views of the downtown 

area. This posed several challenges 

in terms of installation 

constraints and tailor-made system 

layouts were defined for 

each site. 

The Vaisala Automatic 

Weather Station MAWS301, as 

delivered to ARPA Emilia Romagna, 

include the new Vaisala 

Data Logger QML201, a complete 

automatic weather station 

designed on one printed board. 

The board contains a 32-bit Motorola 

CPU for data processing 

and 10 differential (20 single end- 


View from Reggio Emilia site. The urban location of the sites required tailormade 

system lay-outs to be carried out for each installation site. 

ed) analog sensor inputs (these 

can also be used as digital inputs). 

Moreover, there are three frequency 

sensor interfaces, a maximum 

of 6 serial ports, a 16 bit 

A/D converter, 1.7 Megabytes of 

secure Flash memory for data logging, 

as well as a power supply 

and charger for the internal backup 

battery. The board uses the 

latest SMD (Surface Mount Device) 

technology and is coated for 

improved protection in conditions 

of high humidity. 

The operation of the 

MAWS301 can easily be set-up 

and modified using the MAWS 

Lizard set-up program. The 

MAWS Lizard is a software program 

that instructs the 

MAWS301 as to what it should 

measure, log, calculate, and report. 

Measured data is stored in 

the daily log files that can be 

downloaded to a PC and viewed 

using the MAWS Terminal software. 

A basic setup is loaded in 

the MAWS program memory already 

at the factory. This allows 

the customer to simply connect 

the sensors, communication 

lines, and power supply to the 

MAWS301 and have the station 

start operating, making measurements, 

performing calculations 

and sending reports. The customer 

is able to freely reconfigure 

the setup files or make completely 

new ones, by using the Vaisala 

Set-up Software for MAWS. 

The MAWS301 is a low-power 

system and the logger consumes 

less than 10 mA from a 6 V 

battery. The system can be powered 

using a solar panel or optionally 

using a 110/230 AC power 

supply, if heated or optical sensors 

are used. The power consumption 

of the complete system 

depends on the sensors, communication 

devices, and other options 

included in the delivery. For 

example, the MAWS301 with a 

basic set of 5 sensors, each with a 

10-minute measuring interval, has 

an average power consumption of 

10 mA. 

A data link is provided with 

the iConnector iC101, a small 

adapter that enables installed devices 

to use the Internet for messaging 

via wireless modems and 

data-enabled phones that operate 

over AMPS, CDMA, CD- 

PD, GPRS, GSM, iDEN, and 

TDMA wireless networks. iConnector 

provides “Instant Internet” 

connectivity by eliminating 

the need for any hardware 

modification to a host device 

when connecting it to an Internet 

Service Provider (ISP). iConnector 

supports, for example, 

FTP client basic features and enables 

the user to communicate 

with the server using the FTP 

protocol. 

Vaisala has extensive experience 

in the design, manufacture, 

installation, commissioning and 

servicing of complete networks 

of automatic weather stations 

and networks, worldwide. 

Thanks to this diversified and 

large installation experience 

Vaisala has been able to develop 

the most enhanced technical solutions 

in terms of data communication, 

low power consumption 

and high sensor integration 

capability. Research and development 

of the Vaisala Automatic 

Weather Stations is continuously 

ongoing. ● 





Co-operation to improve 

water quality measurement 

The systems used to measure 

the quality and quantity 

of the water in Finland’s 

inland waterways will be 

improved through the co-operation 

between Vaisala Oyj, the 

Finnish Environment Institute 

(SYKE) and the Uusimaa Regional 

Environment Centre. The objective 

of this co-operation is to 

develop measuring systems that 

will provide more accurate information 

on the leaching of nutrients 

into the waterways. It is expected 

that considerable sums of 

money will be saved with the automation 

of these measurements. 

The first stage of the project will 

last two years. The pilot stations 

will be located in Uusimaa, an 

area surrounding Helsinki. 

Vaisala, SYKE and the Uusimaa 

Regional Environment 

Centre have signed a co-operation 

agreement to develop solutions 

for improved water protection 

and water research. The aim 

is to develop measurement instruments 

and measuring sys- 

tems that will provide more accurate 

information on the leaching 

of nutrients into surface waterways. 

The instruments are also 

designed to determine what 

actions will best reduce the nutrient 

load in these waterways. 

The measurement instruments 

and solutions will also be 

applied to hydrological monitoring 

and its development. The target 

is to create a system by which 

sensors will provide users with 

topical information over a GSM 

network. The results of the project 

will be utilized in both national 

and international environmental 

monitoring and research. 

The co-operation between 

Vaisala, SYKE and the Uusimaa 

Regional Environment Centre 

combines the expertise of the 

environmental administration 

authorities and the private sector. 

Vaisala will manufacture and 

develop the measuring systems. 

SYKE will provide expert assistance 

by analyzing and evaluating 

the material, while the Uusimaa 

Regional Environment 

Centre will maintain the measurement 

stations and take samples. 

The three test stations involved 

in the project are located 

in Southern Finland. 

Eutrophication is the biggest 

problem in Finnish waterways. 

The nutrients released into them 

cause point and non-point pollution. 

Typical point sources of 

nutrients include industrial and 

municipal wastewater and fish 

farming. Non-point sources of 

nutrients include agriculture and 

forestry and wastewater in rural 

areas. Over half of the nutrients 

entering the waterways due to 

human action are from agriculture. 

Hydrological conditions affect 

the leaching and transportation 

of these nutrients. ● 


Andy McDonald 

Regional Manager 

Vaisala Road Weather 

Birmingham, UK 

Norwegian Roads safer with 

Vaisala's Remote Measurement 

and Forecasting Technology 

The Norwegian Public Road Administration (NPRA) in Stor-Oslo District has the responsibility 

for procuring and managing contracts from the private sector for the provision of winter service 

on the national highway network in and around Oslo. The public policy is that national 

roads should be kept free from ice and snow at all times. This is a difficult task in Oslo's harsh 

winter climate, one which requires forward planning. Remote measurement and forecasting 

technology has a key role to play in determining the correct winter maintenance action. 

The importance of accurate, 

timely data being 

available 24 hours a day 

is one of the main reasons why 

the NPRA have chosen to contract 

with Vaisala in the UK for 

the provision of a complete data 

management service; a service 

which involves not only the supply 

of remote road weather stations 

but the responsibility for 

ensuring the continuous flow of 

data and forecasts to the NPRA's 

chosen winter service contractors 

around the clock. This service 

is made possible by utilising 

internet connectivity. 

A number of Vaisala weather 

stations are located at strategic 

points on the highway network 

around Oslo. These stations provide 

a continuous source of road 

weather information including 

details of the road surface condition 

and temperature as well as 

the general state of the atmosphere, 

for example visibility and 

type of precipitation falling. The 

information is automatically 

transmitted to Vaisala’s data management 

hub (Bureau) in the UK 

where it is stored and processed 

in a relational database. 

Working in partnership with 

the Norwegian National Meteorological 

Institute (MI), a number 

of 24 hour forecasts are prepared 

each day for the strategic weather 

station points and also transmitted 

to Vaisala’s UK Bureau 

for further processing and storage. 

Forecasts comprise a range 

of graphical and Norwegian text 

products tailored to the requirements 

of the NPRA. Each graphical 

forecast provides detailed information 

on the expected temperature 

and road condition for 

the coming night which can be 

directly compared against measured 

data from the weather station 

points. To complement the 

point forecasts, forecast thermal 

maps of the complete network 

are provided. These indicate 

which sections of road will fall 

below freezing and at what time, 

giving crucial information in sufficient 

time to take preventative 

salting action. 

Online solutions 

provide real-time 

weather station data 

and forecasts 

The NPRA have chosen to access 

the forecast and weather station 

data using a combination of web 

browser and application software. 

The web browser access is 

called IceWeb and is available to 

any of the NPRA’s nominated 

contractors or personnel via the 

use of a password and Internet 

access. For key decision makers, a 

software application called Ice- 

View is loaded on to each nominated 

PC. IceView also makes use 

of the Internet to retrieve weather 

station data and forecasts from 

the Vaisala Bureau. In addition, 

IceView allows the user to manipulate 

the data and change configuration 

information in such a 

way as to tailor the information 

to specific areas. 

Service and calibration 

ensure continuous 

and accurate data 

Continuous and accurate data 

supply are two of the most important 

parameters for NPRA. To 

address these points the data 

management service incorporates 

a number of safeguards and monitoring 

functions. Prior to the 

start of winter each of the weather 

stations are serviced and calibrated 

by Vaisala and the process repeated 

during the course of the 

winter. Once the winter starts the 

Bureau is manned 24 hours per 

day, 7 days per week in order to 

provide a continuous backup and 

ensure a smooth operation. This 

is facilitated by duplicating all 

key points of failure such as Internet 

Service Providers and database 

servers. 

Every time a new piece of 

data is received by the data hub 

from a weather station it is automatically 

scrutinised for error 

and and any evidence of calibration 

drift. If an error does occur 

at any time Vaisala maintenance 

personnel are on constant standby 

ready to carry out repairs in a 

timely fashion and bring the station 

or sensor back online as 

quickly as possible. 

By utilising the Vaisala Bureau, 

NPRA in Stor-Oslo are 

able to delegate the responsibility 

of data management and concentrate 

on the core responsibility 

of managing the highway network. 

The partnership of NPRA, 

Vaisala and MI ensures that the 

driving public around Oslo are 

provided with a level of service 

which both they and the law demand. 

● 

Vaisala's data management hub- The Bureau stores detailed information 

about road weather conditions. 


Timo Honkanen 

Development Manager 



Work on the expansion of the Dubai International Airport has begun and will be completed in 2006. One new 

terminal and two concourses will be built which will almost triple the passenger capacity of the airport. 

Vaisala Upgrades 

Dubai International Airport 

In the beginning of 2004, Vaisala Aviation Weather delivered the new 

Vaisala MIDAS IV Automated Weather Observing System (AWOS) software 

to Dubai International Airport (DIA). It was a very demanding 

upgrade project at one of the most prestigious airports in the world. 

Dubai International 

Airport – best in 

the Middle East 

Dubai International Airport was 

established in 1959 when the 

late Ruler of Dubai, HH Sheikh 

Rashid bin Saeed Al Maktoum, 

ordered its construction. Today, 

DIA is one of the fastest growing 

airports in the world. Furthermore, 

it is recognized as the aviation 

hub and busiest airport in 

the Middle East. In 2003, a total 

of 18 million passengers passed 

through the airport, a 13% 

growth in comparison to 2002. 

Dubai International Airport 

at present has the capacity to 

handle 22 million passengers annually. 

However, by 2010, 60 

million passengers are expected 

to pass through the airport every 

year. With consideration of 

these figures, the Department of 

Civil Aviation began a second 

phase of expansion with a total 

investment of 4.1 billion USD 

in the first quarter of 2002. The 

expansion is scheduled to be 

completed by 2006 and will include 

the construction of a third 

terminal, two concourses and a 

new cargo terminal. Upon the 

completion of the second phase 

the Dubai International Airport 

will have the capacity to handle 

70 million passengers per year. 

High standards of service are 

customary at Dubai International 

Airport. Readers of the magazine 

Business Traveler Germany have 

voted Dubai International Airport 

the “Best in the Middle East and 

Africa” in a recent survey and 

Condé Nast Traveler Magazine 

awarded the airport “Best International 

Airport Worldwide” in 

2003. With this background, it was 

evident that a faultless world-class 

AWOS upgrade solution was the 

only acceptable option at Dubai. 

Software upgrade 

provides 

new functionalities 

The latest Vaisala MIDAS IV 

version 2.0 continues to provide 

International Civil Aviation Organization 

(ICAO) compliant 

AWOS to airports of all sizes. 

Backward compatibility is 

mandatory and therefore the existing 

Vaisala MIDAS IV configuration 

can be utilized in system 

upgrades. Also, the look and 

feel of the user interface remains 

the same to avoid any confusion 

for the users. 

One of the main new features 

is the possibility to use hotstandby 

functionality without 

any special hardware. This LANbased 

duplication allows Vaisala 

MIDAS IV servers to be installed 

anywhere in the network, not 

necessarily in the same rack. The 

LAN can be extended all the way 

to the sensor sites, making the 

system easily expandable. 

If remote connections are 

necessary, a new dial-up service 

can be used to send data to the 

desired remote locations. Further, 

a dial-up or secure Internet connection 

can be used for remote 

diagnostics or maintenance. 

The latest version of the 

Vaisala MIDAS IV includes an 

ICAO compliant runway friction 

application called SNOWTAM. 

SNOWTAM automatically sends 

data to weather reports on the 

friction values of the runway surface. 

Of course the weather conditions 

in Dubai do not require 

the use of SNOWTAMs. 

Vaisala MIDAS IV 

Automated Weather 

Observing System 

upgrade 

Dubai International Airport first 

installed the Vaisala MIDAS IV 

Automated Water Observing 

System in 1999. The primary 

task of the system at DIA is to 

provide real-time weather data 

to end users, and to generate 

weather messages such as 

METAR, TAF and SYNOP for 

the Aeronautical Fixed Telecommunications 

Network (AFTN). 

Vaisala MIDAS IV is a critical 

tool for MET office personnel as 

well as air traffic controllers. In 

addition, Midas IV provides data 

for the Automatic Terminal 


Information System (ATIS). 

From a technical point of 

view, the Dubai system is a largescale 

system, running in a cluster 

of two central data units for 

maximum reliability. End users 

can operate a number of Vaisala 

MIDAS IV workstations at various 

locations around the airport. 

In 2003 Dubai International 

Airport decided to upgrade the 

existing Vaisala MIDAS IV software 

to meet the latest ICAO 

specifications. Also, METAR, 

SYNOP and CLIMAT enhancements 

were needed together 

with some customization. Naturally, 

the airport was required to 

stay operational during the upgrade. 

Vaisala Software Engineer, 

Antti Tölli started preparation 

for this demanding project as 

the Project Manager in late 

2003. Due to many new software 

requirements, Senior Software 

Engineer Hannu Heikkinen was 

also part of the project team 

right from the start. 

Senior Software Engineer Hannu 

Heikkinen and Project Manager 

Antti Tölli were responsible for the 

installation of the upgrade of the 

Vaisala MIDAS IV system at 

Dubai International Airport. 

A challenging 

installation requiring 

careful planning and 

co-operation 

The actual delivery of the system 

took place in February 2004. 

Thanks to careful preparation 

and co-operation with DIA personnel, 

the upgrade was completed 

on-site by Antti and Hannu 

in just two weeks! 

The first day on-site, Antti 

and Hannu met with the local 

AWOS team - Dave Thomas, 

MET Office Manager, Graham 

Orr, Electrical Engineer and 

Sony Antony, Maintenance Engineer. 

The group adjusted the 

implementation plan and schedule 

for the new software and 

hardware installations. Considering 

the overall system complexity 

and the number of flights 

landing and taking off from the 

airport, it was clear that the team 

was faced with a real challenge, 

as there was no allowance for system 

downtime. Dave Thomas, 

FRMetS CMet, Manager, Dubai 

Meteorological Office, Department 

of Civil Aviation stated 

that “having worked with the 

MIDAS IV system for almost 5 

years we had very clear ideas of 

how we wanted to customize the 

system to fit our exact requirements. 

This posed some testing 

problems for Antti and Hannu, 

as a result they worked some 

long days but they always came 

up with a solution in the end.” 

A test system with the new 

hardware and software was set 

up next to the existing system in 

the equipment room. Special 

arrangements were made so that 

both the old and new systems 

were able to run parallel without 

any interference to the normal 

operations. After some fine-tuning 

of the new configuration, the 

system was ready for the Site Acceptance 

Tests (SAT). Thorough 

test procedures were carried out 

by the local AWOS team and after 

three days of intensive site acceptance 

testing, approval was 

given to the new system. 

The most critical moment of 

the upgrade was taking the new 

system into operational use. 

Careful preparations were made 

to ensure a smooth switch to the 

new system. The new computers 

and displays were moved into 

their positions and made ready 

to be plugged in. As afternoons 

are the quietest time at the 

Dubai International Airport, it 

Sheikh Rashid Terminal. 

was the best time to switch over 

to the new system. Once this was 

done the old computers and 

workstations were disconnected, 

the new ones connected and the 

data started to flow in immediately. 

During the hours following 

installation, the operation of 

all critical functions of the system 

were verified, including the 

ATIS and AFTN interfaces. 

Promising future 

The project was a success. The 

new system is up and running 

and the customer is satisfied. 

New technical features introduced 

proved to be useful and 

robust, such as the LAN based 

duplication. Support for LANbased 

sensor communication is 

already implemented in the 

Vaisala MIDAS IV. Whenever 

DIA decides to convert serial 

line connections into full use of 

TCP/IP and fiber optics, Vaisala 

MIDAS IV will be ready to support 

the conversion. 

The co-operation between 

Vaisala Aviation Weather and 

DIA continues and over the 

course of the next few months, a 

new graphical tool and database 

for various data mining needs 

(the automatic extraction of hidden 

information from databases) 

will be installed to the current 

system. Dave Thomas, FRMetS 

CMet, Manager, Dubai Meteorological 

Office, Department of 

Civil Aviation commented that 

“the new system has many improvements 

and some customizations 

that have simplified 

our operational procedures. We 

will continue to work with the 

MIDAS IV team and look forward 

to future developments.” 

The future for the Vaisala 

MIDAS IV Automated Weather 

Observing System seems very 

promising. The upgrade of the 

Dubai International Airport is 

once again further proof that 

Vaisala MIDAS IV continues to 

be the most advanced and versatile 

automated weather observation 

system available. Many new 

ideas and innovative solutions 

are being developed and put into 

practice by the Vaisala MIDAS IV 

system architects which will be 

available to our customers in the 

near future. ● 



Vaisala Helsinki 

Finland 

Vaisala Invests 

6.5 million Euros in 

New Clean Room 

Vaisala's new clean room was taken into operation and 

production of Vaisala's sensors was re-started in May 

2004. The new facility is state-of-the-art and one of the 

few clean rooms in private ownership in Finland. 

In May, 2004 Vaisala's new 

clean room was taken into 

operation. The facility is one 

of the most modern in Finland 

and one of the few clean rooms 

in private ownership. The new 

space is 500 m2 and 1/6 of the 

space is in accordance with the 

ISO 5 standard while the remaining 

5/6 are in accordance 

with the ISO 6 standards. The 

total investment cost of the facility 

was 6.5 million Euros. 

Most of the equipment from the 

previous clean room will be 

moved into the new facility and 

production will begin immediately. 

Vaisala's sensors are manufactured 

in the clean room, a 

nearly particle-free environment 

with no more than 1,000 particles 

larger than 0.5 microns in 

any given cubic foot of air. 

The yellow light in 

one section of the 

clean room protects 

the photosensitive 

layer of wafers from 

excess of UV-light. 

In this section 

patterns are formed 

on wafers by UVexposuring 

the 

photosensitive resist 

through a mask. 

More than 20 years of 

clean room experience 

Vaisala is one of the few private 

companies in Finland to own 

and operate a clean room. The 

previous facility was taken into 

operation in 1981, and built to 

manufacture integrated circuits 

for radiosondes. In the 1990's 

production was concentrated to 

the manufacturing of sensors for 

Vaisala Radiosondes as well as 

the HUMICAP ® and BARO- 

CAP ® . The need for additional 

space and a modernization of the 

After every production step, the sensor-wafers are carefully checked e.g. by a 

microscope inside the clean room before further processing. 

In wet etching the wafers are dipped in chemical baths to achieve metal 

removal from desired parts of the wafer. 


What is a clean room? 

Aclean room is an area where air quality, temperature 

and humdity is carefully regulated to 

ensure that senisitive equipment is protected from 

any possible contamination. The air in the room is 

continuously filtered using HEPA filters to remove 

any dust particles or other impurities which could 

damage any highly sensitive materials being produced 

or worked with. In the ISO 5 standard pat of 

the room the air is circulated/changed 400 times per 

hour and in the ISO 6 100 times/hour. 

All staff working in a clean room must wear special 

protective clothing called "bunny suits" to ensure 

that no fibers, hair or skin are added to the room's atmosphere. 

The International Standards Organization (ISO) 

has set standards for the number of particles allowed 

per cubic foot of air. The Vaisala Clean Room is in accordance 

with the ISO 5 and ISO 6 standards which 

means that in any cubic foot of air there are no more 

than 100 (ISO 5) or 1,000 (ISO 6) particles larger than 

0.5 microns. ● 

The row of wet benches are used to wet etching, resisit removal and cleaning of 

wafers. 

exisiting room lead to the decision 

to invest in the new facility. 

The clean room is used to 

manufacture sensors for internal 

use as well as for product development 

and research. The ability to 

manufacture sensors internally ensures 

the high quality of Vaisala's 

sensors. Annually, approximately 

900,000 sensors are produced in 

the clean room. The majority of 

these sensors are used in Vaisala 

Radiosondes, but a portion of 

them are also used in Vaisala's humidity 

and pressure products. 

The investment in the new 

clean room will ensure that 

Vaisala's customers will continue 

to receive high-technology products 

providing relaible and accurate 

measurements. ● 

The wafers are placed inside an oven and heated to 300 degrees Celcius in 

order to harden the thin polymer layer. 

The number of particles in the air are monitored regularly in order to ensure 

that they are kept within the proper range. 





Secretary General of the World Mete 

Mr. Michel Jarraud, Secretary-General of the World Meteorological 

Organization (WMO) visited Finland on one of his first official visits 

to a member state since taking up the post as Secretary-General in 

January. Mr. Jarraud views Finland as an appropriate first visit since 

it is an important partner and active member of the WMO, very 

active in the industrial sector and a partner in supporting developing 

countries. His visit was arranged by the Finnish Meteorological 

Institute and included a visit to Vaisala where Mr. Pekka Ketonen, 

President and CEO of Vaisala gave a presentation of Vaisala and 

a tour of the production facilities and the new clean room. 

Pekka Ketonen, President and CEO of Vaisala shows Mr. Jarraud, Secretary General of the WMO how 

the Vaisala Radiosondes are produced. 

Vaisala News had the opportunity 

to speak to 

Mr. Jarraud and hear his 

views on the future challenges 

facing his organization, weather 

in general and the the role private 

organizations such as 

Vaisala will have in the future. 

The WMO falls under the 

umbrella of the United Nations 

(UN) with a membership of 187 

member states and territories. It 

was established in 1950 and is the 

specialized agency of the UN for 

meteorology, including weather 

and climate, operational hydrology 

and related geophysical sciences. 

The WMO is the UN's authoritative 

voice on the status of 

the world's atmosphere including 

how it interacts with the oceans 

and affects the climate. 

Vaisala is an important 

provider of equipment used to 

collect the necessary measurement 

data of a wide variety of 

weather parameters used by 

many of the national weather 

services around the world. 

Natural 

disaster prevention, 

an important 

development area 

Weather has become increasingly 

important on the international 

agenda in recent years with 

much focus being placed on climate 

change and natural disasters. 

Mr. Jarraud believes that we 

are living in an exotic time 

where nature impacts all areas of 

human activity. He says "the 

prevention of natural disasters is 

important for developed countries 

and even more important 

for developing countries who are 

generally more vulnerable to 

these phenomenon. Approximately 

80% of disasters are meteorological 

or hydrological." He 

believes that disaster prevention 

will be a top priority for the future 

as the countries shift towards 

disaster preparedness 

rather than disaster relief. 

Mr. Jarraud believes that climate 

change will become an increasingly 

important area for the 

WMO to focus more on in the 

future. The WMO is playing an 

important role by co-ordinating 

high-standard observational networks 

and ensuring that data 

and products are shared freely 

on a global level. These networks 

are showing a change in the 

earth's climate which will have 


orological Organization visits Vaisala 

impacts on many facets of human 

life. 

Challenges facing 

the WMO in the future 

Mr. Jarraud believes that an important 

and major challenge facing 

the WMO is the co-operation 

between the WMO and national 

weather services, NGO's, 

local authorities and private organizations. 

He feels that there 

is a need for a new approach to 

cooperation and a need to develop 

an aggressive policy to communicate 

weather-related issues. 

There will be a need to ensure 

that the gap between the developed 

and developing countries 

is decreased and increasingly 

there will be a need to develop 

good models to involve private 

organizations in the WMO's activities. 

Differences between 

member states 

Another area, which will pose a 

challenge to the WMO in the 

future, is the gap between the 

developed countries and the developing 

countries. Decreasing 

this gap has been a priority for 

the WMO for many years now 

and Mr. Jarraud believes that 

new technology can bridge this 

gap. The less developed countries 

will need access to products, 

information on the use of 

products and training and education 

in order to catch up to the 

more developed countries. Currently 

the major obstacle in 

many countries is the cost of data 

as it is difficult to maintain 

the quality of data at a low cost. 

Mr. Jarraud states that many 

countries have a hard time to 

meet the monetary needs needed 

to obtain quality data. This 

can be a question of a need for 

better-trained personnel to a 

need for financial resources. He 

believes that private organizations 

will have an important role 

to play in finding ways to lower 

the cost of equipment. 

The role of 

private organizations in 

the WMO 

All member countries have representatives 

from their national 

meteorological services in the 

WMO, however, private organizations 

are becoming increasingly 

involved today. Mr. Jarraud 

states that Vaisala is one of the 

more involved private organizations 

today. He continues to say 

that the provision of services by 

private organizations is evolving 

and developing and that there 

will be a need for the WMO in 

the future to find mechanisms to 

interact with the private sector 

even more on the local, national, 

international and WMO level. 

The instrument organization 

that Vaisala is co-operating in 

may be used as a model for other 

areas as well. There is a need to 

try and possibly use different 

models to co-operate with the 

private sector on. 

Co-operation 

with Vaisala 

The Vilho Väisälä prize was established 

in 1985 and is administered 

by the WMO to encourage and 

stimulate interest and support in 

important research areas which 

support the WMO's programs in 

the field of meteorological and 

climatic observation methods 

and instruments. Mr. Jarraud sees 

the award as a very visible and 

prestigious prize. Vaisala and the 

WMO are currently looking into 

ways to further develop the award 

and new directions are being explored. 

Mr. Jarraud stated that 

the cooperation between the 

WMO and Vaisala has been very 

valuable to the WMO and that 

he looks forward to continuing 

this in the future. ● 

Jan Hörhammer of Vaisala shows Mr. Jarraud a sensor which has been 

produced in Vaisala's clean room. 

Mr. Ketonen explains how the Vaisala Radiosondes are calibrated. 



Vaisala Helsinki 

Finland 

In Vaisala 

Thirty years of 

Excellence in 

Humidity 

Measurement 

Thirty years ago Vaisala presented 

a completely new 

way of measuring humidity. 

Vaisala HUMICAP ® ‚ Sensor, the 

world's first thin-film capacitive 

humidty sensor was brought onto 

the market. Three decades 

later Vaisala has become the 

world market leader in the 

measurement of relative humidity 

and kept its place as a pioneer 

in the development in 

state-of the art humidty instruments. 

More information can be 

found on www.vaisala.com 

Annual Results for 

2003 Released 

V 

aisala's 

net sales for 2003 

totaled EUR 189.2 million 

and the operating profit of the 

Group was EUR 25.9 million. 

Growth in demand stopped in 

early 2002 and has been unstable 

across all business areas. Despite 

this situation the company's 

operating profit grew by 

14.7% compared with 2002. The 

improved result, depsite lower 

net sales, can be attributed to 

measures to improve profitability. 

These measures will have full 

effect in 2004. Vaisala is listed 

on the Helsinki Stock Exchange 

(HEX). For more information or 

to read the Annual Report for 

2003 please visit www.vaisala. 

com/annualreport 

Vaisala to sponsor 

the 18 th 

International 


Conference 

The International Lightning 

Detection conference will 

be held in Helsinki the 7th to the 

9th of June 2004. The conference 

theme will be “New Understanding 

of the Relationships 

and Impacts of Lightning: Improving 

Real-world Applications 

with Advances in Detection Research 

and Data Integration.” 

The ILDC, a biannual conference, 

provides a unique and important 

forum for presentations 

and discussion related to education, 

research, and applications 

development in lightning detection 

technologies. ILDC presenters 

and attendees share a common 

passion for understanding 

lightning and how it affects the 

world we live in. Professionals in 

the fields of aerospace, atmospheric 

research, aviation, data 

center management, emergency 

response management, electrical 

engineering, electric power, 

explosive and ordnance management, 

forestry, golf and 

recreation, lightning research, 

meteorology, mining, telecommunications 

and weather media 

are invited. 

European 

Meteorological 

Annual Meeting 

The 4th Annual Meeting of 

the European Meteorological 

Society (EMS) will be held 

September 26-30th in Nice, 

France. Vaisala will participate 

in the meeting and will organize 

a customer workshop during 

the week to present Vaisala's 

new products such as the Thunderstorm 

Information System 

and the Vaisala Soundings division's 

equipment for upper air 

weather observations. Additional 

information about Vaisala's 

workshop can be found on 

www.vaisala.com/News & Events 

and more information on the 

EMS annual meeting can be 

found at http://www.copernicus.org/ems/2004 

Mesoscale workshop 

held in Boulder 

V 

aisala 

co-organized a workshop 

entitled Design and 

Development of Multi-functional 

Mesoscale Observing Networks 

in Support of Integrated 

Forecasting Systems in December. 

The goal of the workshop 

was to develop recommendations 

and identify areas for continued 

research and development 

of improved mesoscale observing 

systems. These developments 

will be based on the 

needs of users, modelers (including 

those engaged in data assimilation), 

and forecasters. The 

focus was placed on identifying 

the challenges, needs and opportunities 

involved in the development 

of improved, economically 

viable, integrated atmospheric 

mesoscale observing, 

modeling and information-delivery 

systems. The potential users 

of these systems include federal, 

state and local agencies in addition 

to private weather information 

providers and end-user 

groups. 

A consensus has emerged 

within the observational, modeling 

and forecasting communities 

that carefully designed, integrated 

mesoscale systems will 

improve short-term forecasts in 

the future. To realize the full 

benefits of enhanced forecast 

modeling there is a need to improve 

the high-resolution observations 

of all meteorological 

variables, in addition to improvements 

in data assimilation, 

model physics, parameterizations, 

and end-user-specific analyzes 

and forecast products. 

Improved mesoscale 

systems yield improved 

short term forecasts 

Improved mesoscale systems are 

able to deliver forecasts of the 

physical and chemical state of 

the atmosphere including precipitation, 

ground state and 

run-off. These systems provide 

accurate, timely and user-relevant 

forecasts useful for improved 

short-term forecasts of 

severe weather, flash flooding 

for the use of water management, 

energy production and 

management, agriculture, air 

quality, homeland security and 

public health to name a few. 

Next steps 

The workshop was organized in 

joint cooperation between 

Vaisala, the University of Oklahoma 

and the NOAA Forecast 

Systems Laboratory. The formal 

report summarizing the findings 

and recommendations from the 


workshop will be available at 

the end of April and will be reported 

in the next weather observation 

issue of Vaisala News. 

Additional information on the 

workshop can be found at 

http://www.mmm.ucar.edu/ 

uswrp/upcoming_meetings/ 

announcement2.html 


Aviation Weather 

participates in 

ATC Maastricht 2004 

V 

aisala's 

Aviation Weather 

participated in ATC Maastricht 

February 10-12, 2004. 

Maastricht is the annual meeting 

place for the leading ATC 

(Air Traffic Control) and ATM 

(Air Traffic Management) industry 

global suppliers. 


displayed solutions for aviation 

weather observations and introduced 

several new products including 

the new tranmissometer 

for runway visual range assessment, 

the new ceilometer for 

cloud height measurements and 

vertical visibility measurements. 

Vaisala arranged an Aviation 

Weather Seminar in conjunction 

with the exhibition. An 

overview of the present and future 

developments in the 

Vaisala Aviation Weather unit 

was presented and a group of 

experts discussed the latest 

products in the industry covering 

a wide array of items spanning 

from sensors to service contracts. 

Mr. Pekka Utela from Vaisala 

presented a paper entitled 

Sales Managers Kim Kaijasilta and Ingo Schesonka present Vaisala Aviation 

Weather to customers at the Vaisala stand. 

“Specifying visibility and cloud 

instruments”. The presentation 

covered current technologies 

for cloud and visibility measurement 

as well as international 

standards for measurement performance. 

Particular focus was 

placed on the key performance 

areas that are currently not adequately 

covered by common 

standards as well as suggestions 

for improving the methods of 

specifying cloud and visibility instruments 

were suggested. 

The three day show attracted 

more than 2,800 visitors from 

approximately 80 countries. 

Most of the participants are 

from civil aviation authorities, 

governmental departments, air 

navigation providers, airports 

and airport authorities and it is 

a unique opportunity for the 

major supplier of air traffic control 

equipment, training and 

communications to meet their 

customers. ● 

Klaus Heyn of Vaisala presents the new 

Vaisala Transmissometer. 


Europe 


P.O. Box 26, FI-00421 Helsinki 

FINLAND 

Telephone: +358 9 894 91 

Telefax: +358 9 8949 2227 


Malmö Office 

Drottninggatan 1 D 

S - 212 11 Malmö 

SWEDEN 

Telephone: +46 40 298 991, 

in Sweden: 0200 848 848 

Telefax.: +46 40 298 992, 

in Sweden: 0200 849 849 

Vaisala GmbH 

Hamburg Office 

Schnackenburgallee 41 

D-22525 Hamburg 

GERMANY 

Telephone: +49 40 839 030 

Telefax: +49 40 839 03 110 


Bonn Office 

Adenauerallee 46 a 

D-53113 Bonn 

GERMANY 

Telephone: +49 228 912 5110 

Telefax: +49 228 912 5111 


Bremerhaven Office 

Buchtstrasse 45 

27570 Bremerhaven 

GERMANY 

Telephone: +49 471 170 1655 

Telefax: +49 471 170 1755 


Stuttgart Office 

Pestalozzi Str. 8 

D-70563 Stuttgart 

GERMANY 

Telephone: +49 711 734 057 

Telefax: +49 711 735 6340 

Vaisala Ltd 

Birmingham Operations 

Vaisala House 

349 Bristol Road 

Birmingham B5 7SW 

UNITED KINGDOM 

Telephone: +44 121 683 1200 

Telefax: +44 121 683 1299 

Vaisala Ltd 

Newmarket Office 

Unit 9, Swan Lane 

Exning 

Newmarket 

Suffolk CB8 7FN 

UNITED KINGDOM 

Telephone: +44 1638 576 200 

Telefax: +44 1638 576 240 

Vaisala SA 

Paris Office 

2, rue Stéphenson (escalier 2bis) 

F-78181 Saint-Quentin-en-Yvelines 

Cedex 

FRANCE 

Telephone: +33 1 3057 2728 

Telefax: +33 1 3096 0858 

Vaisala SA 

Aix-en-Provence Office 

7, Europarc Ste-Victoire 

F-13590 Meyreuil 

FRANCE 

Telephone: +33 4 4212 6464 

Telefax: +33 4 4212 6474 

North America 

Vaisala Inc. 

Boston Office 

10-D Gill Street 

Woburn, MA 01801 

USA 

Telephone: +1 781 933 4500 

Telefax: +1 781 933 8029 


Columbus Office 

7450 Industrial Parkway 

Plain City, Ohio 43064-9005 

USA 

Telephone: +1 614 873 6880 

Telefax: +1 614 873 6890 


Boulder Operations 

194 South Taylor Avenue 

Louisville, CO 80027 

USA 

Telephone: +1 303 499 1701 

Fax: +1 303 499 1767 


Sunnyvale Office 

260 Santa Ana Court 

Sunnyvale, CA 94085-4512 

USA 

Telephone: +1 408 734 9640 

Telefax: +1 408 734 0655 


Tucson Operations 

2705 East Medina Road 

Tucson, Arizona 85706, USA 

Telephone: +1 520 806 7300 

Telefax: +1 520 741 2848 

U.S. Toll Free 1 800 283 4557 


Houston Office 

1120 Nasa Road 1 Suite 220-E 

Houston, TX 77058 

Telephone: +1 281 335 9955 

Telefax: +1 281-335-9956 

Vaisala Inc. Regional Office Canada 

P.O. Box 2241, Station “B” 

London 

Ontario N6A 4E3 

CANADA 

Telephone: +1 519 679 9563 

Telefax: +1 519 679 9992 

Asia and Pacific 

Vaisala KK 

Tokyo Office 

42 Kagurazaka 6-Chome 

Shinjuku-Ku 

Tokyo 162-0825 

JAPAN 

Telephone: +81 3 3266 9611 

Telefax: +81 3 3266 9610 

Vaisala KK 

Osaka Office 

Thick Land Building 1203 

2-3-5 Nanba Chuo-ku, Osaka 542-0076, 

Japan 

Telephone: +81 6 62123954 

Telefax: +81 6 62123955 

Vaisala Pty Ltd 

Melbourne Office 

3 Guest Street 

Hawthorn, VIC 3122 

AUSTRALIA 

Telephone: +61 3 9818 4200 

Telefax: +61 3 9818 4522 

Vaisala Beijing Representative Office 

CITIC Building 

19 Jianguomenwai Dajie 

Chaoyang District 

Beijing 100004 

People’s Republic of China 

Telephone: +86 10 8526 1199 

Telefax: +86 10 8526 1155 

Vaisala Beijing Representative Office 

in Shanghai 

c/o Kaukomarkkinat 

Room 402A West Tower, Sun Plaza 

88 Xian Xia Road 

Shanghai, P.R. China 200336 

Telephone: +86 21 62700642/41 

Telefax:+86 21 62700640 

Vaisala Regional Office Malaysia 

Level 36, Menara Citibank 

165 Jalan Ampang 

50450 Kuala Lumpur 

MALAYSIA 

Telephone: +60 3 2169 7776 

Telefax: +60 3 2169 7775 

C210029EN 2004-05

Vaisala News 165 - Full Magazine

You also want an ePaper? Increase the reach of your titles

Delete template?

Save as template?