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LAKE ICE MONITORING
Polar View's lake ice monitoring service
delivers EO-derived information about the location and extent of ice
covers to decision makers in near real-time. This information is typically
used in conjunction with other data sources to assess the level of threat
posed by the freezing and melting. The freeze-up and the break-up dates
are an indicator of the impact climate change is having on the environment.
As a result of global warming, the difficulties
that a shorter or more unpredictable ice season brings to isolated northern
communities have become a recent concern. There are a number of factors
that contribute to the duration of ice cover, including precipitation,
wind, sunshine, and various attributes of the water body itself, such
as size and characteristics of its currents. The timing of ice break-up
in the spring is more variable because the amount of snow cover and
coldness of the preceding winter also play a role. Air temperature affects
both the freeze-up and the break-up dates, changes in the timing of
these events allow for a good reflection of trends in temperatures.
Lake Ice Impacts on Ecosystems and Resources
Presence and thickness of lake ice has
a significant impact on fish ecology, particularly in terms of over-wintering
habitats for certain species. The Lake Ice Service team of Hatfield
Consultants Ltd. will be focussing its efforts on studying the dynamics
of the ice in lakes and rivers of two study sites in Ungava Bay, Northern
Quebec. The Payne River on the west and George River on the eastern
side of the bay are two of the main habitats for Arctic Char (Salvelinus
alpinus) in the region, providing nutrition and livelihoods to local
Inuit communities. The formation and thickness of ice in specific rivers
and lakes in these two areas has a significant impact on the existence
and sustainable harvesting of arctic char as large quantities of char
over-winter in the lakes, migrating to the sea in the summer.

Participating in Traditional Ecological Knowledge (TEK)
interviews
Hatfield Consultants Ltd. are working
with the Nunavik Research Centre of the Makivik Corporation to develop
appropriate EO-based geo-information products that can be integrated
with existing Traditional Ecological Knowledge (TEK) to be more effective
in understanding and sustainably managing these ecosystems and resources.
Furthermore, the extent and nature of the impacts of climate change
in this region are still not fully understood. The long-term possibilities
of year-to-year monitoring of ice presence and thickness are also being
explored in order to address the information needs of managers and scientists
monitoring the effects of climate change.

A schematic representation of the Service
Chain for the Lake Ice Service

Study area of the Lake Ice Service
End Users
Local Communities
Nunavik Research Centre (Makivik Corporation)
References
Jeffries, M.O., K. Morris, W.F. Weeks
and H. Wakabayashi. 1994. Structural-Stratigraphic Features and ERS-1
SAR Backscatter Characteristics of Ice Growing on Shallow Lakes in N.W.
Alaska, Winter 1991-92. Journal of Geophysical Research, 99(C11): 22459-22471.
Kozlenko, N. and M. O. Jeffries. 2000.
Bathymetric mapping of shallow water in thaw lakes on the North Slope
of Alaska with spaceborne imaging radar. Arctic, 53(3), 306-316.
Duguay, C.R., T.J. Pultz, P.M. Lafleur,
and D. Drai. 2002. RADARSAT Backscatter Characteristics of Ice Growing
on Shallow Sub-Arctic Lakes, Churchill, Manitoba, Canada. Hydrological
Processes 16:1631-1644.
Duguay, C.R. and P.M. Lafleur. 2003. Estimating
Depth and Ice Thickness of Shallow Subarctic Lakes using Spaceborne
Optical and SAR Data. International Journal of Remote Sensing 24: 475-489.
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