|GLOBAL CLIMATE OBSERVING SYSTEM
ESSENTIAL CLIMATE VARIABLE - Ice sheets
|Domain||Terrestrial||Description||Our understanding of the timescale of ice sheet response to climate change has changed dramatically over the last decade. Rapid changes in ice-sheet mass have surely contributed to abrupt changes in climate and sea level in the past. [GCOS-195 6.3.7]
|Full Name||Ice sheets
|Satellite Signficant Contribution||Yes
*GCOS-195 Status Categories:
Category A: Action completed, perhaps exceeding reasonable expectations. Very good progress on ongoing tasks.
Category B: Action largely completed according to expectation. Good progress on ongoing tasks.
Category C: Moderate progress overall, although progress may be good for some part of the action.
Category D: Limited progress overall, although progress may be moderate or good for some part of the action.
Category E: Very little or no progress, or deterioration rather than progress.
|Description||Who||Time Frame||Performance Indicator||Cost Implications
|Ensure continuity of laser, altimetry, and gravity satellite missions adequate to monitor ice masses over decadal timeframes.||Space agencies, in cooperation with WCRP CliC and TOPC.||New sensors to be launched: 10-30 years.||Appropriate follow-on missions agreed.||30-100M US$ (Mainly by Annex-I Parties).
from CEOS DB
|T.4||Ice-sheet elevation changes, supplemented by fields of ice velocity and ice mass change||Surface elevation change|
|Ice sheet topography
|CEOS Response||[T20 (T.4)]
2015 Update: Ice_sheets_cci consists of two projects covering the Greenland and Antarctic ice sheets respectively. Both projects provide the same set of ECV parameters:
Consistency with Glaciers_cci is ensured to avoid double-counting of glaciers, and to ensure all areas of ice-loss are covered.
- Surface Elevation Change (1991-2017) over the whole ice sheets from radar altimeters on ERS-1, ERS-2, Envisat, ICESat, Cryosat, AltiKa and Sentinel-3.
- Ice Velocity from ERS-1, ERS-2, Envisat ASAR, Sentinel-1, Radarsat, Palsar and TerraSAR- X (1991-2017)
- West Antarctic Ice Sheet and Antarctic Peninsula
- Greenland ice sheet (2014-2017) from Sentinel-1 SAR
- Main Greenland glaciers (1991-2017)
- Grounding Line Location from multi-sensor InSAR - ERS-1, ERS-2, Envisat, Sentinel-1, Palsar and TerraSAR-X (1991-2017)
- GRACE-derived mass balance (2002-present)
- Calving Front Location for major outlet glaciers from ERS, Envisat, Sentinel-1 and Sentinel-2. (1991-2017)
The projects founded, coordinated and participated in the international Ice Sheet Mass Balance Intercomparison Exercise (IMBIE), and the IPCC Coordinating lead author on ice sheets is closely involved as Chair of the projects' Climate Research Groups.
Annual cost: seems low. ICESat-2 is $700M, NISAR will be $1.2 B, GRACE follow on ~ $300M
For InSAR, please quote the NASA ISRO SAR (NISAR) mission which was recently made official between India and the US, and will be the first InSAR dedicated mission looking at ice sheets.
For future/current missions:
- The EU is providing access to Sentinel-1a and 1b (InSAR), which are tremendously useful.
- CSA will launch RADARSAT-3 and a RADARSAT constellation (I think R-3 will be part of that).
- There is GRACE follow on but also GRACE-2.
- Landsat-8 is useful for ice motion (when no cloud).
- The EU will launch Sentinel-3 (altimetry).