Geoscience Reference
In-Depth Information
Climate impacts and adaptation in Canada's North
The importance and urgency of adapting to climate change impacts in
Canada's North has been the focus of a considerable body of research. For
example, the Arctic Climate Impact Assessment (ACIA) states that
the Arctic, together with the Antarctic Peninsula, experienced the great-
est regional warming on earth in recent decades, due largely to various
feedback processes. Average annual temperatures have risen by about 2
to 3°C since the 1950s and in winter up to 4°C. The warming has been
largest over the land areas.
(Arctic Climate Impact Assessment 2005:3)
Other Arctic climate trends include rising river flows, declining snow cover,
increasing precipitation (roughly 8 per cent across the Arctic over the past
100 years), thawing permafrost, diminishing lake and river ice, melting
glaciers, retreating summer sea ice and changes in ocean salinity (Hassol
2004). The climate trends affect many natural ecosystems, such as by shift-
ing distributions of plant and animal species northward, and impact both
atmospheric and biogeochemical processes, e.g. penetration of UV radiation
and carbon cycling (Häder et al . 2007; Zepp et al . 2007). This unprecedented
warming brings extreme events and has caused the international insurance
industry to take note of climate change and the ensuing increase in natural
catastrophes (Vellinga and van Verseveld 2000; Diffenbaugh et al . 2005;
Katz and Brown 2007; National Round Table on the Environment and
the Economy 2009). In response to the impacts of these changes to human
systems, we need to adapt our engineering, construction and maintenance
practices to the changes in northern climates. The impacts of these changes
are evident now, and will be even more acute during the coming decades.
The Arctic Climate Impact Assessment provides a comprehensive look at
the impacts of climate change in the Arctic, which helps us determine
the need and time frames required for adaptation (Arctic Climate Impact
Assessment 2005).
In Canada's North, we are faced with permafrost thawing and degrada-
tion, slumping of ice-laden landforms and changes in timing of freeze-up and
melting of river ice and sea ice (Furgal and Prowse 2008). For example, in the
central Arctic Ocean, submarine sonar measurements have revealed a 40 per
cent reduction in ice thickness (Hassol 2004). Gas hydrates, sometimes con-
sidered to be an energy source that is twice as abundant as all the known oil,
gas and coal on our planet combined, are buried in permafrost on land and in
off-shore sea beds. The northward movement of the permafrost boundary due
to Arctic warming trends releases the methane that is held in these hydrates.
The methane adds to the total greenhouse gas emissions, bringing yet more
global warming.
 
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