Table 1. Rates of ice-bonded permafrost table deepening in the study area.
Boreholes 1982/83 versus 2013/14 | Latitude °N | Longitude °E | Water depth (m.b.s.l.) | Core length (m) | Depth of IBPT* 1982 (m.b.s.l.) | Years since inundation to 1982† | Rate of IBPTD cm per year before 1982 | Depth of IBPT 2013/14 (m.b.s.l.) | Change in depth of IBPT from 1982 to 2013/14‡ | Rate of IBPTD cm per year from 1982/83 to 2013/14§ |
---|---|---|---|---|---|---|---|---|---|---|
a | b | c | d | e | f | g | h | i | j | k |
301/4D-14 | 71° 36′ | 129° 55′ | 2.5 | 9.5 | 4.2 (3.3) | 49±0.7 | 8.5±0.02 | 8.6 | 4.4 (5.3) | 15.1±1.6 |
303/4D-13 | 71° 37′ | 129° 55′ | 2.5 | 21 | 5.8 (7) | 114±10 | 5.2±0.38 | 11.4 | 5.6 (4.4) | 18.3±0.1 |
304/3D-14 | 71° 37′ | 129° 54′ | 2.7 | 17.6 | 8.6 (8.3) | 170±21.7 | 5.2±0.6 | 12.8 | 4.2 (4.5) | 13.5±0.2 |
305/2D-13 | 71° 37′ | 129° 52′ | 3.4 | 30.4 | 16.8 (16) | 429±9.2 | 3.9±0.01 | 19.3 | 2.5 (3.3) | 9.3±1.7 |
IBPT, Ice-bonded permafrost table.
S.e.m. in columns h and k reflects variability between values calculated from the two groups of numbers presented in columns f and j.
*Data presented in column f are from20; numbers in parentheses are original data from drilling report provided by Grigoriev.
†Years since inundation calculated as described in Methods section.
‡Numbers in parentheses calculated from values presented in parentheses in column f.
§Rates of IBPTD from 1982 to 2013/2014 derived from j/31 for boreholes 4D-13 and 2D-13 or j/32 for boreholes 4D-14 and 3D-14.