Geology Reference
In-Depth Information
Table 5.2 .
Global distribution of permafrost. (A) According to Baranov (1959) and Shi (1988).
(B) The extent of permafrost in the northern hemisphere based on continuity and ground
ice content, as portrayed in the IPA Circum-Arctic map of permafrost and ground ice
(Brown et al., 1997).
(A)
Northern Hemisphere (million km
2
)
Southern Hemisphere
(million km
2
)
Russia (Former Soviet Union)
11.0
Antarctica
13.5
Mongolian People's Republic
0.8
China
2.1
North American continent
(a) Alaska
1.5
(b) Canada
5.7
Greenland
1.6
Tot a l
2 2 .7
1 3. 5
Total for both hemispheres
36.2 million km
2
149.0 million km
2
Total land area for both hemispheres
Area occupied by permafrost
24 per cent
(B)
Area, 10
6
km
2
(%)
Extent of permafrost
Lowlands/uplands with
Mountains with
thick overburden
thin overburden
High
Med
Low
High
Low
Total
>
20%
10 -20%
0 -10%
>
10%
10%
Continuous
1.49
1.31
0.38
2.14
5.66
10.98
(90-100%)
(5.9)
(5.1)
(1.5)
(8.4)
(22.2)
(43.1)
Discontinuous
0.08
0.87
0.38
0.75
2.34
4.42
(50-90%)
(0.3)
(3.4)
(1.5)
(2.9)
(9.2)
(17.3)
Sporadic
0.11
0.31
0.56
0.32
2.66
3.96
(10 -50%)
(0.4)
(1.2)
(2.2)
(1.3)
(10.4)
(15.5)
Isolated
0.34
0.07
0.60
0.03
2.85
3.89
(0-10%)
(1.3)
(0.3)
(2.4)
(0.1)
(11.2)
(15.3)
Relict
0.12
(0.5)
Total area
2.02
2.56
1.92
3.24
13.51
23.37
Permafrost (%)
(8.6)
(11.0)
(8.3)
(14.1)
(58.2)
(100)
Source:
Frozen Ground
, 22, 1998 (back cover).
5.4.1. Latitudinal Permafrost
The broad distribution of latitudinal permafrost is relatively well known. In addition to
the IPA Circum-arctic Map of Permafrost and Ground Ice (Brown et al., 1997), a number
of more detailed permafrost maps are available for Alaska (Ferrians, 1965), northern
Canada (Natural Resources Canada, 1995; Heginbottom and Radburn, 1993), and Russia
