D-BAUG - Departement Bau, Umwelt und Geomatik - ETH Zürich

Key Article ▪ Juneau Icefield Research Program
The Juneau Icefield Research Program –
A long-term study on the implications of climate change
Glaciers are significant indicators for climate change and research teams around the
globe try to analyze and understand the process of glacial changes. The Juneau Icefield
in Alaska has been subject to such research since 1946 and measurements for the inter-
pretation of climate change implications are available for more than 60 years. The geo-
detic surveys and processed data serve as basic data for this purpose.
by Werner Stempfhuber / IGP; Melanie Kunz / IKA
Approximately 5% of Alaska is permanently covered by ice
and snow. The Juneau Icefield is referred to as 5th largest
contiguous glacial area in the western hemisphere and
covers an area of over 4000 km2. Situated in the north of
the Alaskan capitol Juneau, the Icefield consists of about
140 glaciers, some as long as 30 km and the main glacier
with the name of Taku is over 1400 m thick. The area was
mapped by the Preliminary Boundary Survey from 1983 to
1894 and again from 1906 to 1910 with more sophisticated
methods. After World War II the Juneau Icefield Research
Program (JIRP) was founded under the leadership of Dr.
Maynard M. Miller (University of Idaho). Since 1946 JIRP expeditions
are run every year which makes the Juneau Icefield
one of the most explored glacial areas worldwide.
The Juneau Icefield Research Program (JIRP)
Every summer scientists cross the Juneau Icefield with a
group of students from the southern end towards Atlin
(Canada) in the north. Equipped with the latest survey
hardware they gather and analyze data to answer glaciological
questions in the domain of glacier dynamics and
mass balance. The scope of the research and training program
is to offer practical projects based on the following
fields: glaciology, hydrology, geology, geomorphology, geophysics,
geodesy, photogrammetry, remote sensing, meteorology,
botany, as well as environmental and resource
protection.This long-term study produces answers to current
questions about climate change through countless
publications and dissertations (crevassezone.org/reports-
JIRP.htm). The extensive JIRP infrastructure encompasses
around 20 base camps and allows for a convenient stay on
the icefield. However, research teams and students have to
cover the 150 km long way across the glaciers only with
their skis, carrying all their gear with them. And exactly
these experiences fascinate every JIRP participant and
make an unforgettable memory (Fig. 1). In the year 2009 an
22 ▪ D-BAUG Annual Report 2009
ETH staff member was able to actively join this research
program and spend an amazing summer in Alaska.
JIRP is run by the Glaciological & Arctic Sciences Institute
of the University of Idaho and by the Foundation for Glacier
and Environmental Research. The collected information
about the program and an extensive literature list are available
at crevassezone.org and www.juneauicefield.com.
Surveying the Juneau Icefield
From 1946 to 2009 countless surveys have been conducted,
the data analyzed and visualized. Because the early surveys
were based on theodolite and distance measurements, a
holistic processing of all available survey data is not fully
possible. Since 1992 all longitudinal and cross sections on
the icefield are surveyed with the help of 2-frequency GPS
receivers and for the last few years also with GLONASS receivers.
With this global surveying method processing and
visualization of the geodetic data are possible in a continuous
system. In Figure 3 (upper left) all surveyed longitudinal
and cross profiles are presented graphically in a georeferenced
LandSat-satellite picture. With the available
stakeout and reference points the profiles can easily be staked
out and measured in real-time.The two plots of results
(Fig. 3, upper right and middle) show the changes over the
years exemplary for a profile on Taku glacier.Together with
the information on annual layers gathered in the snow pits,
mass balances can be modeled. Some cross profiles are
measured twice during the season, which provides information
on the flow rate of the glacier surface. On Taku
glacier this velocity is over 60 cm per day (Fig. 3, bottom).
Long-term surveys on Lemon Creek glacier (Fig. 4, left),
which have been analyzed and evaluated in connection with
the International Geophysical Year of the American Geographical
Society between 1957 to 1999, resulted in a decrease
of the total mass from 901 x 106 km 3 to 695 x 106 km 3 . This