Projected Climate Change and Variability and Their Impact on the Canadian Rocky Mountains - Impact of Global Changes on Mountains: Responses and Adaptation - page 403

Annual DJF JJA

10ºC
7
5
4
3.5
3
2.5
2
1.5
1
0.5
0
-0.5
-1

70ºN 70ºN 70ºN

50ºN 50ºN 50ºN

30ºN 30ºN 30ºN

10ºN 10ºN 10ºN

180º 140ºW 100ºW 60ºW 20ºW 180º 140ºW 100ºW 60ºW 20ºW 180º 140ºW 100ºW 60ºW 20ºW

50%
30
20
15
1 5
-5
-10
-15
-20
-30
-50

70ºN 70ºN 70ºN

50ºN 50ºN 50ºN

30ºN 30ºN 30ºN

10ºN 10ºN 10ºN

180º 140ºW 100ºW 60ºW 20ºW 180º 140ºW 100ºW 60ºW 20ºW 180º 140ºW 100ºW 60ºW 20ºW

21 Models
19-20
17-18
14-16
8-13
5-7
3-4
1-2
0

70ºN 70ºN 70ºN

50ºN 50ºN 50ºN

30ºN 30ºN 30ºN

10ºN 10ºN 10ºN

180º 140ºW 100ºW 60ºW 20ºW 180º 140ºW 100ºW 60ºW 20ºW 180º 140ºW 100ºW 60ºW 20ºW

Figure 18.4. Source: Figure 11.12 of IPCC-AR4 (2007), Chapter 11 of Working Group 1.
Color image of this figure appears in the color plate section at the end of the topic.

(as much as 15 to 20%) over the southern areas of the Canadian Rocky
Mountains. It should be noted that there is less confi dence in climate change
projections by a global climate model at regional and local scales than, say
at an overall continental scale. But it becomes extremely problematic for
extreme climatic events at a regional scale.
In the recent past, we have noted that extreme weather events
(collectively described as climatic variability) have usually produced
disastrous impacts on our socio-economic systems. IPCC-AR4 (2007) has
summarized the results of many studies that indicate, under a warming
climate, we will see signifi cant changes in temperature and precipitation
extremes in the 21st century in many regions of the world. That is, the
climate will become more variable. Intensity, Duration and Frequency (IDF)
of extreme weather events, such as the heat wave, will increase. Projected
amplifi cation of the hydrological cycle by the climate models will lead to
intensifi cation of precipitation events (snow and rain) over some regions
while other regions will face prolong drought periods.
Although global and regional climate models simulate a general
decrease in snow depth in the Rocky Mountains with global warming