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hydrology and sedimentary systems; permafrost degradation; hazards caused by
cryospheric changes; and trends of glacier retreat on the global scale along with the
impact of climate change.
Singh et al. (2011) note that the earth
s cryosphere, which includes snow, glaciers
and ice caps, ice sheets, ice shelves, sea ice, river and lake ice, and frozen ground,
contains about 75 % of the earth
'
s fresh water. It exists at almost all latitudes, from the
tropics to the poles, and plays a vital role in controlling the global climate system. It
also provides direct visible evidence of the effect of climate change, and, therefore,
requires proper understanding of the complex dynamics.
'
5.3.5 Other Climatic Parameters
Data on global soil temperature (GST) are important for climate diagnostics. As
Majorovicz et al. (2002) have noted, an analysis of the GST data obtained in
different regions of Canada by measuring the ground temperature in bore-holes,
revealed considerable spatial differentiation both in GST increase observed in the
20th century, and in the onset of the warming. For instance, from measurements in
21 bore-holes covering a period of the last 1,000 year, warming was detected
(within 1
C) during the last 200 years. The warming was preceded by a long
cooling trend in the region 80 ° - 96 ° W, 46 ° - 50 ° N, which continued until the
beginning of the 19th century. According to data for ten bore-holes in central
Canada, the temperature had reached a minimum about the year 1820 with a
subsequent warming by about 1.5
3
°
-
°
C. In western Canada, during the last 100 years
the warming reached 2
C.
An analysis has been made by Majorovicz et al. (2002) of more adequate
information on GST from data of measurements in 141 bore-holes at a depth of
several hundred meters. The holes were drilled in 1970
°
1990. The results obtained
-
revealed an intensive warming that started in the 18
19th centuries, which followed
a long period of cooling (especially during the Little Ice Age), continuing during
the rest of the millennium. The time of the onset of the present warming differed
between regions. An analysis of the spatial distribution of the GST changes over the
territory of Canada revealed a substantial delay in the onset of the present warming
in the east-to-west direction, with a higher level of the GST increase in the 20th
century in western Canada. This conclusion is con
-
rmed by the data of SAT
observations. It should be noted that the GST increase in eastern Canada had begun
about 100 years before the industrial era.
Characteristics of the atmospheric general circulation are important components
of climate diagnostics. Wallace and Thompson (2002) pointed out that the west-
eastern zonal wind component averaged over the 55
N latitudinal belt can be a
representative indicator of the primary mode of the surface air pressure anomalies
°
the Northern Hemisphere annual mode (NAM) that is hemispheric scale patterns of
climate variability. Both NAM and a similar index SAM for the Southern Hemi-
sphere are typical signatures of symbiotic relationships between the meridional
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