Title

Decay of glaciers, ice caps and ice sheets

Author(s)Ohmura, Atsumu

Citation

地球温暖化による劇変を解明する．平成20年6月24日．札幌市

Issue Date

2008-06-24

Doc URL

http://hdl.handle.net/2115/34392

TypeFile Information

conference presentation

15-3.pdf

Instructions for use

Hokkaido University Collection of Scholarly and Academic Papers : HUSCAPDrastic Change in the Earth System during Global Warming

Decay of glaciers, ice caps and ice sheets
Atsumu Ohmura
Institute for Atmospheric and Climate Science
Swiss Federal Institute of Technology (E.T.H.)
Zurich, Switzerland
Ohmura@env.ethz.chGlobal cryosphere area and volume (July, 2007)
Cryosphere
Seasonal snow coverSea ice
Glaciers
Permafrost
Total

Area in [106 km2]
4 (19) ~ 46 (58)15.0 ~ 21.5
15.92358 ~ 78 x 106 km2

Volume0.5 (1) ~ 5 (6) x 103 km319 ~ 25 x 103 km3
33.1 x 106 km3
0.4 x 106 km3 (11-35x103 km3)
33.5 x 106 km3

Glacier ice distribution[106 km2]
Antarctic
13.59 (86 %)Greenland
1.75 (11 %)Others (Mountain glaciers 0.55 (3 %)and ice caps)
Total
15.89 x 106 km2[106 km3]
30.11 (90.9 %)2.93 (8.8%)
0.10 (0.3 %)33.14 x 106 km3

Rhonegletscher 1982

Rhonegletscher 2006

Triftgletscher2002

Triftgletscher 2005

Global mean for 1961-1990 = 14.0°C+0.66°C/Century

+1.3°C/Century-0.2+1.8

Approximate flux

Mean normalized global radiation for the 5 sites with long-term pyrheliometry.

Wm-2

140

5.4 W m-2

135

3.8 W m-2

125
Odessa, Moscow, Tartu, CH, Tateno

Detection of important changes in radiation
1.
2.

Global dimming & brightening
Possible increase in long-wave incoming radiation

BSRN trend

Decadal global change in radiation
Change in terrestrial irradiance
1950-1990+1.0 Wm-2/Decade
1991-2007+2.5
Change in solar irradiance
1950-1990-4.5 Wm-2/Decade
1991-2007+4.1
Change in Total irradiance
1950-1990-3.0 Wm-2/Decade
1991-2007+6.6

Austre Brøggerbreen
Midre Lovénbreen

Engabreen
StorbreenÅlfotbreenNigårdsbreen

Claridenfirn
Glacier de SarennesGråsubreen
Hellstungubreen

Rembesdalsskåla

Vernagtferner

Storglaciären

Leviy Aktru
Maliy Aktru
No.125 (Vodopadniy

Djankuat

Tsentralniy Tuyuksuyskiy

Abramov

Urmuqihe No.1
Kara Batkak

Meighen Ice Cap
Melville South Ice Cap
Devon Ice Cap
GulkanaWolverinePlace
HelmPeytoSouth Cascade

Global mean pentade annual net mass balance

Pentade period
1960/61-1964/65
1965/66-1969/70
1970/71-1974/75
1975/76-1979/80
1980/81-1984/85
1985/86-1989/90
1990/91-1994/95
1995/96-1999/00
2000/01-2004/05
Total over 45 years

ms mass b.
mm/a-308
-178
-90
-294
-203
-314
-411
-496
-541
-14,175 mm

Sea-level
mm/5 a
2.4
1.4
0.7
2.2
1.5
2.4
3.1
3.8
4.1
21.6 mm

Estimate of the mass balance of the Greenland ice sheet
Surface area: 1,756 x 103 km2
TotalMeanice volume specific balance Source
km3 W.E. y-1
mm W.E. y-1
Annual precipitation on Greenland
753346
Ohmura et al. (1999)
Annual precipitation on tundra
163379ditto
Annual precipitation on ice-covered area
Loss through evaporation/sublimation
Loss by run-off as liquid precipitation

590
61
13340
358

ditto
ditto
ditto

Annual accumulation
Melt
Calving
Rate of storage

516
297
316-91297
169
180-52dittoThis work
Reeh (1994), E. Rignot (PC)This workSea-level influence during the 20th century
1. Small glaciers and ice caps

4.7 cm

2. Greenland

2.53. Antarctic

10 ?

4. Thermal expansion of ocean2

5. Other sources?

Gauge

17 cm