7th Workshop on Forest Fire Management - EARSeL, European ...

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III - FIRE DETECTION AND FIRE MONITORING
Imaging Spectroradiometer (MODIS) by NASA in 1999 and 2002 provided
the world with a tool to be used inter alia in fire tracking.
In early 2004 Eskom and the Council of Scientific and Industrial Research
(CSIR), launched a research project to demonstrate the ability to track
active fires by using polar orbiting satellites. MODIS being medium-resolution
scanner enables four updates daily with a 1km 2 resolution [1]. The
detection of grass fires as small as 0.25ha is possible with this data [2].
Eskom required information on fires every 15 minutes and whilst the MODIS
data was sufficiently high in spatial resolution, the temporal resolution was
less than satisfactory. Consequently the CSIR proposed the use of the
Spinning Enhanced Visible and Infrared Imager (SEVIRI) sensor on board
the Meteosat Second Generation (MSG) satellite. This satellite is in geostationary
orbit above the equator and the SEVIRI sensor transmits data every
15 minutes. MSG data is observed at a spatial resolution of 5km 2 [3]. Once
the processing of the hot spots have been completed the information is
published on a website, and e-mail alerts are sent. Due to the fact that the
Eskom field personnel are normally out on patrols, the idea emerged to send
text message warning of fires to their mobile phones. In the case of power
lines, only the fires within 2,5km of the line are reported. Where possible,
the National Control Centre could temporarily switch out the lines under
threat and the field staff can activate fire suppression teams where available.
Field staff also report to the control centre on the conditions at the
site of the fire. This system was the first of its kind in the world where an
electrical utility applied remote sensing together with cell phone technology
in the monitoring of fires under power lines.
3 - Vegetation management in 2009
In addition to the real-time use of the system, the use of historic data
accumulated by the system is proving to be most helpful in the management
of the Transmission system. History on fires close to transmission
lines is now available since 2003 and this information is used to track past
performance as well as planning vegetation management strategies for the
future. In Table 1 the number of fires detected close to power lines gives
an indication of the extent of the fire season and is used to evaluate fire
prevention and reduction strategies. The planning of vegetation management
has three main objectives. They are:
• Ensure safe electrical clearances;
• Ensure access to the line for inspection and maintenance;
• Reduction of fuel loads to reduce the effects of fires.