Observational Requirements
GCW observational requirements are being formulated. They will draw from various sets of existing user requirements and will be vetted by the scientific community. They will become part of the WMO Rolling Review of Requirements (RRR) and will be accessible through the Observing Systems Capability Analysis and Review Tool (OSCAR). The IGOS Cryosphere Theme Report (see Documents) contains the most comprehensive set of observational capabilities and requirements for the cryosphere. It is the starting point for GCW. The IGOS Cryosphere Theme requirements are given below. Click the Filter Options button to filter the results. Each entry in the table gives the current measurement capability in green, the threshold requirement (minimum necessary) in blue, and the objective requirement (target) in orange, if available.
For current WMO snow and ice requirements, explore OSCAR.
Use the checkboxes and lists to filter the results. You can select multiple variables by using shift-, control-, or command-click combinations. Multiple selections within a row mean "or"; selections across the rows mean "and". For example, if snow depth, sea ice extent, IGOS and CliC aare selected, all entries that are snow depth or sea ice extent and either IGOS or CliC requirements are displayed. No selections for a row is identical to checking all boxes in that row. Leave everything unchecked and click Filter for all database entries.
Variable |
Element | Application Area | Special Conditions | Measurement Range, Low | Measurement Range, High | Uncertainty |
Spatial Res | Temporal Res | Timeliness | Source | Date Valid | Comments |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Ice thickness | Sea ice | IGOS | Climate | 0 m 0 m 0 m | 10 m 10 m 10 m | 0.5 m - 0.1 m | 0.5 km - 25 km | 0.5 year - 1 month | - - - | IGOS 2007 | 2007-11-01 | ICESat, op ice charts, mass balance buoys, AUV Sat, altimeter, mass balance buoys, AUV |
| Ice thickness | Sea ice | IGOS | Operational | 0 m 0 m 0 m | 10 m 10 m 10 m | 10% - 10% | 0.5 km - 0.5 km | 1 week - 1 day | - - - | IGOS 2007 | 2007-11-01 | ICESat, op ice charts, mass balance buoys, AUV Sat, altimeter, mass balance buoys, AUV |
| Ice motion | Sea ice | IGOS | Climate | 0 km day-1 0 km day-1 0 km day-1 | 100 km day-1 100 km day-1 100 km day-1 | 5 km day 3 km day-1 1 km day-1 | 25 km 25 km 1 km | 1 day 1 day 1 day | - - - | IGOS 2007 | 2007-11-01 | AMSR2, SAR2, Buoys SAR More frequent SAR, improved MIZ performance |
| Ice motion | Sea ice | IGOS | Operational | 0 km day-1 0 km day-1 0 km day-1 | 100 km day-1 100 km day-1 100 km day-1 | 0.5 km day-1 3 km day -1 0.5 km day-1 | 1 km 25 km 0.1 km | 3 day 1 day 1 day | - - - | IGOS 2007 | 2007-11-01 | AMSR2, SAR2, Buoys SAR More frequent SAR, improved MIZ performance |
| Surface characteristics | Sea ice | IGOS | Albedo, melt pond concentration | 0% 0% 0% | 100% 100% 100% | 10% 10% 1-5% | 1 km 1 km 0.5 km | 1 day 1 day 1 day | - - - | IGOS 2007 | 2007-11-01 | MODIS, but not currently produced, AUV MODIS, but not currently produced, AUV MODIS, but not currently produced, AUV |
| Snow depth on ice | Sea ice | IGOS | Climate | 0 cm 0 cm 0 cm | 100 cm 100 cm 100 cm | 10-20 cm 5 cm 2 cm | 15 km 10 km 5 km | 1 day 1 day 1 day | - - - | IGOS 2007 | 2007-11-01 | AMSR CIMS CIMS |
| Ice surface temperature | Sea ice | IGOS | 190 K 200 K 200 K | 290 K 275 K 275 K | 2-3 K 1 K 0.1 K | 1 km 1 km 0.1 km | 100 min 60 min 30 min | - - - | IGOS 2007 | 2007-11-01 | Hydromet Hydromet | |
| Extent/Edge | Sea ice | IGOS | Climate | NA, km NA, km NA, km | NA, km NA, km NA, km | 15 km 10 km 5 km | 15 km 10 km 1-5 km | 1 day 1 day 1 day | - - - | IGOS 2007 | 2007-11-01 | AMSR, VIR, SAR, AUV CIMS CIMS, SAR, AUV |
| Extent/Edge | Sea ice | IGOS | Operational | NA, km NA, km NA, km | NA, km NA, km NA, km | 0.1 km 10 km 0.1 km | 0.1 km 10 km 0.1 km | 3 day 1 day 1 day | - - - | IGOS 2007 | 2007-11-01 | AMSR, VIR, SAR, AUV CIMS CIMS, SAR, AUV |
| Ice concentration | Sea ice | IGOS | Climate | 15% 0% 0% | 100% 100% 100% | 5-20% <10 % <5 % | 15 km 15 km 10 km | 1 day 1 day 1 day | - - - | IGOS 2007 | 2007-11-01 | AMSR, VIR, SAR, AUV CIMS, SAR, AUV |
| Ice concentration | Sea ice | IGOS | Operational | 0% 0% 0% | 100% 100% 100% | 5-20 % <10 % <5 % | 15 km 15 km 10 km | 1 day 1 day 1 day | - - - | IGOS 2007 | 2007-11-01 | AMSR, VIR, SAR, AUV CIMS, SAR, AUV |
| Leads/polynyas | Sea ice | IGOS | Climate | 0% - 0% | 100% - 100% | 5-20% - 5% | 15 km - 10 km | 1 day - 1 day | - - - | IGOS 2007 | 2007-11-01 | AMSR, SAR, AUV MODIS, PM, AUV |
| Leads/polynyas | Sea ice | IGOS | Operational | 0 km2 - 0 km2 | indet. km2 - indet. km2 | 0.1 km2 - 0.1 km2 | 0.5 km - 0.1 km | 1 day - 1 day | - - - | IGOS 2007 | 2007-11-01 | AMSR, SAR, AUV MODIS, PM, AUV |
| Ice Age | Sea ice | IGOS | Climate | 0% 0% 0% | 100% 100% 100% | 5-20% <10 % <5 % | 15 km 15 km 10 km | 1 day 1 day 1 day | - - - | IGOS 2007 | 2007-11-01 | SSMI, VIR, Scat, SAR SAR SAR |
| Ice Age | Sea ice | IGOS | Operational | 0% 0% 0% | 100% 100% 100% | 5-20% <10 % <5 % | 15 km 15 km 10 km | 1 day 1 day 1 day | - - - | IGOS 2007 | 2007-11-01 | SSMI, VIR, Scat, SAR SAR SAR |
| Ridge height | Sea ice | IGOS | Climate | 0 m 0 m 0 m | 10 m 10 m 10 m | - 2 m 1 m | - - - | - - - | - - - | IGOS 2007 | 2007-11-01 | SAR SAR SAR |
| Ridge height | Sea ice | IGOS | Operational | - 0 m - | - 10 m - | - 2 m - | - - - | - - - | - - - | IGOS 2007 | 2007-11-01 | SAR SAR SAR |
| Melt onset, Duration of melt | Sea ice | IGOS | Climate | 1 day 1 day 1 day | 365 day 365 day 365 day | 4 day 2 day 1 day | 15 km 15 km 10 km | 1 day 1 day 1 day | - - - | IGOS 2007 | 2007-11-01 | AMSR, Scat |
| Volume/Mass flux | Sea ice | IGOS | Climate | - - 0 km3 day-1 | - - indet. | - - 1 km3 day-1 | - - 25 km | - - 1 day | - - - | IGOS 2007 | 2007-11-01 | Derived from motion, thickness, concentration Derived from motion, thickness, concentration Derived from motion, thickness, concentration |
| Snow water equivalent | Snow | IGOS | Satellite, shallow | 0 m 0 m 0 m | 0.2 m 0.3 m 0.3 m | 2-10 cm 3 cm 2 cm | 25 km 0.5 km 0.1 km | - 1 day 12 hour | - - - | IGOS 2007 | 2007-11-01 | e.g. AMSR-E Hydromet Hydromet |
| Snow water equivalent | Snow | IGOS | Satellite, deep | - 0.3 m 0.3 m | - 3 m 3 m | - 10% 7% | - 0.5 km 0.1 km | - 6 day 12 hour | - - - | IGOS 2007 | 2007-11-01 | Need HF SAR Hydromet Hydromet |
| Snow water equivalent | Snow | IGOS | In situ, shallow | 0 m 0 m 0 m | 3 m 3 m 3 m | 1 cm 1 cm 1 cm | 1 m 1 m 1 m | 30 day 7 day 1 day | - - - | IGOS 2007 | 2007-11-01 | Hydromet Hydromet Hydromet |
| Snow depth | Snow | IGOS | Satellite, shallow | 0 m 0 m 0 m | ~0.7 m 1 m 1 m | 6-35 cm 10 cm 6 cm | 25 km 0.5 km 0.1 km | 1 day 6 day 1 hour | - - - | IGOS 2007 | 2007-11-01 | e.g. AMSR-E Hydromet Hydromet |
| Snow depth | Snow | IGOS | Satellite, deep | - 1 m 1 m | - 10 m 10 m | - 10% 6% | - 0.5 km 0.1 km | - 6 day 1 hour | - - - | IGOS 2007 | 2007-11-01 | Need HF SAR Hydromet Transportation |
| Snow depth | Snow | IGOS | In situ | 0 m 0 m 0 m | 10 m 10 m 10 m | 1 cm 1 cm 1 cm | 1 m 1 m 1 m | 1 day 6 hour 1 hour | - - - | IGOS 2007 | 2007-11-01 | Hydromet Hydromet Hydromet |
| Snow cover | Snow | IGOS | 20% 0% 0% | 100% 100% 100% | 15-20 % 10% 5% | 1 km 0.5 km 0.1 km | - 1 day 12 hour | - - - | IGOS 2007 | 2007-11-01 | e.g. MODIS Hydromet Hydromet | |
| Ice concentration | Freshwater Ice | IGOS | - 0% 0% | - 100% 100% | - 10% 5% | 100 m - 1 km 100 m 30 m | 1 week 1 day 1 day | - - - | IGOS 2007 | 2007-11-01 | Radarsat, AVHRR, OLS AMSR-E, SAR, optical SAR, optical | |
| Ice areal extent | Freshwater Ice | IGOS | - - - | - - - | - 10% 5% | 250-500 m 100 m 30 m | 1 day 1 day 1 day | - - - | IGOS 2007 | 2007-11-01 | MODIS SAR, optical SAR, optical | |
| Freeze-up and break-up date | Freshwater Ice | IGOS | - - - | - - - | 1 day 2 day 1 day | point 100 m 30 m | - 1 year 1 year | - - - | IGOS 2007 | 2007-11-01 | In situ obs. SAR, optical SAR, optical | |
| Freshwater ice thickness | Freshwater Ice | IGOS | 0 m 0 m 0 m | 5 m 3 m 5 m | 2 cm 5 cm 2 cm | point 100 m 10 m | 1-2 week 1 week 1 day | - - - | IGOS 2007 | 2007-11-01 | In situ obs. SAR, passive microwave SAR, passive microwave | |
| Snow depth on ice | Freshwater Ice | IGOS | 0 m 0 m 0 m | 1 m 0.8 m 1 m | 2 cm 5 cm 2 cm | point 100 m 10 m | 1-2 week 1 week 1 day | - - - | IGOS 2007 | 2007-11-01 | In situ obs. SAR, passive microwave SAR, passive microwave | |
| Areal extent of floating/grounded ice | Freshwater Ice | IGOS | - - - | - - - | - 10% 5% | 10 m 5 m 3 m | 1 week 1 week 1 week | - - - | IGOS 2007 | 2007-11-01 | SAR SAR SAR | |
| River ice jams and dams | Freshwater Ice | IGOS | - - - | - - - | - 10% 5% | 0.5 m 10 m 3 m | 1 hour 1 day 1 day | - - - | IGOS 2007 | 2007-11-01 | Aerial Survey SAR, optical SAR, optical | |
| Flooding extent caused by jams and dams | Freshwater Ice | IGOS | - - - | - - - | - 10% 5% | 10 m 5 m 3 m | 1 week 1 day 1 day | - - - | IGOS 2007 | 2007-11-01 | Radarsat SAR, optical SAR, optical | |
| River icings (aufeis) | Freshwater Ice | IGOS | - - - | - - - | - 10% 5% | 15-30 m 10 m 3 m | 2 month 1 week 1 week | - - - | IGOS 2007 | 2007-11-01 | Landsat, ASTER, SAR SAR, optical SAR, optical | |
| Ice sheet margin | Ice sheet | IGOS | 0 km 0 km 0 km | 1000 km 1000 km 1000 km | 2 km 2 km 25 m | 2 km 2 km 25 m | 5 year 5 year 1 year | - - - | IGOS 2007 | 2007-11-01 | AVHRR Hi-res optical and SAR Hi-res optical and SAR | |
| Grounding line | Ice sheet | IGOS | 0 km 0 km 0 km | 1000 km 1000 km 1000 km | 1 km 1 km 100 m | 1 km 1 km 1 km | 5 year 5 year 1 year | - - - | IGOS 2007 | 2007-11-01 | Hi-res optical/InSAR Hi-res optical/InSAR | |
| Surface accumulation | Ice sheet | IGOS | 0 cm water eq/yr 0 cm water eq/yr 0 cm water eq/yr | 50 cm water eq/yr 50 cm water eq/yr 50 cm water eq/yr | 1 cm water eq/yr 1 cm water eq/yr 1 cm water eq/yr | 25 km 25 km 1 km | 1 year 1 year 6 month | - - - | IGOS 2007 | 2007-11-01 | Passive microwave, P/E/ models and in situ Active/ passive microwave Active/ passive microwave | |
| Basal melt magnitude | Ice sheet | IGOS | 0 m/yr 0 m/yr 0 m/yr | 20 m/yr 20 m/yr 20 m/yr | 100 cm/yr 100 cm/yr 10 cm/yr | 10 km 10 km 1 km | 1 year 1 year 6 month | - - - | IGOS 2007 | 2007-11-01 | Inferred | |
| Basal melt distribution | Ice sheet | IGOS | 0 km2 0 km2 0 km2 | 104 km2 104 km2 104 km2 | 1 km 1 km 1 km | 50 km 50 km 10 km | 1 year 1 year 1 year | - - - | IGOS 2007 | 2007-11-01 | UHF/VHF radar UHF/VHF radar | |
| Surface elevation | Ice sheet | IGOS | 0 km 0 km 0 km | 4 km 4 km 4 km | 50 cm 50 cm 50 cm | 1 km 1 km 1 km | 1 year 1 year 1 year | - - - | IGOS 2007 | 2007-11-01 | Radar and laser altimeter Radar and laser altimeter | |
| Surface elevation change | Ice sheet | IGOS | 0 m/yr 0 m/yr 0 m/yr | 5 m/yr 5 m/yr 5 m/yr | 10 cm/yr 10 cm/yr 10 cm/yr | 5 km 5 km 1 km | 1 year 1 year 6 month | - - - | IGOS 2007 | 2007-11-01 | Radar and laser Radar and laser | |
| Snow/Firn density | Ice sheet | IGOS | 0 kg/m3 0 kg/m3 1 kg/m3 | 910 kg/m3 910 kg/m3 910 kg/m3 | 50 kg/m3 50 kg/m3 50 kg/m3 | 100 km 100 km 100 km | 5 year 5 year 5 year | - - - | IGOS 2007 | 2007-11-01 | In situ obs In situ obs | |
| Snow grain size and shape | Ice sheet | IGOS | 2 kg/m3 3 kg/m3 4 kg/m3 | 3 mm 3 mm 3 mm | 0.25mm 0.25mm 0.25mm | 100 km 100 km 100 km | 5 year 5 year 5 year | - - - | IGOS 2007 | 2007-11-01 | Optical and in situ | |
| Ice sheet surface temperature | Ice sheet | IGOS | 5 kg/m3 6 kg/m3 7 kg/m3 | 278 K 278 K 278 K | 1 K 1 K 1 K | 10 km 10 km 10 km | 1 year 1 year 1 month | - - - | IGOS 2007 | 2007-11-01 | In situ obs Annual average THIR Annual average THIR | |
| Internal temperature | Ice sheet | IGOS | 8 kg/m3 9 kg/m3 10 kg/m3 | 273 K 273 K 273 K | 0.1 K 0.1 K 0.1 K | 500 km 500 km 500 km | 5 year 5 year 5 year | - - - | IGOS 2007 | 2007-11-01 | Borehole temp. Borehole temp. | |
| Gravity field | Ice sheet | IGOS | - - - | - - - | 2 mgal 2 mgal 0.5 mgal | 1 km 1 km 1 km | 1 year 1 year 1 year | - - - | IGOS 2007 | 2007-11-01 | Airborne Gravity Airborne Gravity | |
| Surface velocity field | Ice sheet | IGOS | 0 km/yr 0 km/yr 0 km/yr | 15 km/yr 15 km/yr 15 km/yr | 10 m/yr 10 m/yr 10 m/yr | 100 km 100 km 100 km | 6 month 6 month 6 month | - - - | IGOS 2007 | 2007-11-01 | GPS and inSAR GPS and inSAR | |
| Vertical velocity variation | Ice sheet | IGOS | 0 m/yr 0 m/yr 0 m/yr | 1 m/yr 1 m/yr 1 m/yr | 10 cm/yr 10 cm/yr 10 cm/yr | 50 km 50 km 1 km | 5 year 5 year 5 year | - - - | IGOS 2007 | 2007-11-01 | Vertical strain guages Vertical strain guages | |
| Ice sheet thickness | Ice sheet | IGOS | 0.01 km 0.01 km 0.01 km | 4 km 4 km 4 km | 20 m 20 m 20 m | 50 km 50 km 1 km | 10 year 10 year 10 year | - - - | IGOS 2007 | 2007-11-01 | Ice sheet wide VHF and UHF radar VHF and UHF radar | |
| Internal layer depth | Ice sheet | IGOS | 0.01 km 0.01 km 0.01 km | 4 km 4 km 4 km | 20 m 20 m 20 m | 1 km 1 km 1 km | 10 year 10 year 10 year | - - - | IGOS 2007 | 2007-11-01 | VHF and UHF radar VHF and UHF radar | |
| Iceberg calving rate | Ice sheet | IGOS | 0 km/yr 0 km/yr 0 km/yr | 30 km/yr 30 km/yr 30 km/yr | 1 km/yr 1 km/yr 1 km/yr | 1 km 1 km 1 km | 1 year 1 year 6 month | - - - | IGOS 2007 | 2007-11-01 | Inferred | |
| Changes in ice sheet morphology | Ice sheet | IGOS | E.g. crevasses, shear margins | 0 m 0 m 0 m | 100 m 100 m 100 m | 100 m 100 m 100 m | 1 km 1 km 1 km | 1 year 1 year 1 year | - - - | IGOS 2007 | 2007-11-01 | Hi-Res optical and inSAR Hi-Res optical and inSAR |
| Surface melt extent | Ice sheet | IGOS | 0 x 106 sq km 0 x 106 sq km 0 x 106 sq km | 20 x 106 sq km 20 x 106 sq km 20 x 106 sq km | 2500 km2 2500 km2 2500 km2 | 25 km 25 km 10 km | 1 day 1 day 1 day | - - - | IGOS 2007 | 2007-11-01 | Passive and active microwave Passive and active microwave | |
| Surface melt duration | Ice sheet | IGOS | 0 Melt days 0 Melt days 0 Melt days | 100 Melt days 100 Melt days 100 Melt days | 1 Melt day 1 Melt day 1 Melt day | 25 km 25 km 1 km | 1 day 1 day 1 day | - - - | IGOS 2007 | 2007-11-01 | Passive and active microwave Passive and active microwave | |
| Ice sheet mass change | Ice sheet | IGOS | 0 km3/yr 0 km3/yr 0 km3/yr | 200 km3/yr 200 km3/yr 200 km3/yr | 50 km3/yr 50 km3/yr 10 km3/yr | 500 km 500 km 500 km | 1 year 1 year 1 year | - - - | IGOS 2007 | 2007-11-01 | Flux approach not included in this category Satellite Gravity Satellite Gravity | |
| Geothermal heat flux | Ice sheet | IGOS | 0 w/m2 0 w/m2 0 w/m2 | 1 w/m2 1 w/m2 1 w/m2 | 1 w/m2 1 w/m2 1 w/m2 | 1000 km 1000 km 100 km | 10 year 10 year 10 year | - - - | IGOS 2007 | 2007-11-01 | TBD approach TBD approach | |
| Glacier area | Glacier | IGOS | - 0.01 km2 0.01 km2 | - - - | 3% 3% 1% | 30 m 50 m 15 m | 5 year 5 year 1 year | - - - | IGOS 2007 | 2007-11-01 | Landsat etc. Hi-res optical | |
| Glacier area | Glacier | IGOS | - - - | - - - | 1% - - | 5 m - - | 30 year - - | - - - | IGOS 2007 | 2007-11-01 | Airborne | |
| Glacier topography | Glacier | IGOS | 0 m sl. 0 m sl. - | 8500 m sl. 8500 m sl. - | 5 m 0.1 m - | 100 m 30 m - | 5 year 1 year - | - - - | IGOS 2007 | 2007-11-01 | For Models Mass Balance | |
| Glacier velocity | Glacier | IGOS | 0 km/yr 0 km/yr - | 10 km/yr 10 km/yr - | 5% 1% - | 10 m 20 m - | 1 year 1 month - | - - - | IGOS 2007 | 2007-11-01 | InSAR, hi-res optical, etc. InSAR, hi-res optical, etc. In situ | |
| Glacier dammed lakes | Glacier | IGOS | 0.05 km2 0.01 km2 - | 10 km2 10 km2 - | 3% 1% - | 50 m 15 m - | 1 month 5 day - | - - - | IGOS 2007 | 2007-11-01 | SAR, hi-res optical SAR, hi-res optical Airborne | |
| Facies, snowline | Glacier | IGOS | - - - | - - - | - 200 m 30 m | point 100 m 30 m | - 1 month 10 day | - - - | IGOS 2007 | 2007-11-01 | In situ Position of boundary Position of boundary | |
| Accumulation | Glacier | IGOS | - 0.05 0.1 | - 8 m 5 m | 5% 10% 5% | point 500 m 100 m | - 1 year 1 month | - - - | IGOS 2007 | 2007-11-01 | In situ Ku-, X-SAR Ku-, X-SAR | |
| Glacier mass balance | Glacier | IGOS | - 0 0 | - ±5 m ±5 m | 0.1 m 0.2 m 0.05 m | point 500 m 100 m | - 1 month 1 year | - - - | IGOS 2007 | 2007-11-01 | In situ Process model & SAR Process model & SAR | |
| Glacier ice thickness | Glacier | IGOS | 0 - - | 200 m - - | 2-5 m - - | 100 m - - | 30 year - - | - - - | IGOS 2007 | 2007-11-01 | In situ, airborne | |
| Limit of iceberg area | Iceberg | IGOS | NA NA NA | NA NA NA | 10 km 10 km 10 km | 10 km 10 km 10 km | 1 day 2 hour 2 hour | - - - | IGOS 2007 | 2007-11-01 | SAR, SLAR, airborne reconnaissance SAR, SLAR, airborne reconnaissance SAR, SLAR, airborne reconnaissance | |
| Concentration of icebergs | Iceberg | IGOS | 0% 0% 0% | 100% 100% 100% | 10% <10% <5% | 1 deg 1 deg 1 deg | 1 day 1 day 1 day | - - - | IGOS 2007 | 2007-11-01 | SAR, SLAR, airborne reconnaissance SAR, SLAR, airborne reconnaissance SAR, SLAR, airborne reconnaissance | |
| Iceberg position | Iceberg | IGOS | NA NA NA | - - - | 10% <10% <5% | 1 km 1 km 1 km | 1 day 1 day 2 hour | - - - | IGOS 2007 | 2007-11-01 | SAR, SLAR, airborne reconnaissance SAR, SLAR, airborne reconnaissance SAR, SLAR, airborne reconnaissance | |
| Iceberg size | Iceberg | IGOS | 0.01 km 0.001 km 0.001 km | km km km | 30% 30% 30% | 0.01 km 0.01 km 0.001 km | 1 day 1 day 1 hour | - - - | IGOS 2007 | 2007-11-01 | SAR, SLAR, airborne reconnaissance SAR, SLAR, airborne reconnaissance SAR, SLAR, airborne reconnaissance | |
| Iceberg draft | Iceberg | IGOS | 1 m 1 m 1 m | m m m | 30% 30% 30% | 10 m 1 m 1 m | 1 day 1 day 2 hour | - - - | IGOS 2007 | 2007-11-01 | shipborne, modelling altimeter (for large bergs) altimeter | |
| Iceberg mass | Iceberg | IGOS | 0 kg 0 kg 0 kg | kg kg kg | 30% 30% 30% | 15 km 15 km 10 km | 1 day 1 day 2 hour | - - - | IGOS 2007 | 2007-11-01 | shipborne, modelling altimeter (for large bergs) altimeter | |
| Iceberg velocity | Iceberg | IGOS | 0 km day-1 0 km day-1 0 km day-1 | 30 km day-1 30 km day-1 30 km day-1 | 10% 10% 10% | 1 km day-1 1 km day-1 0.5 km day-1 | 1 day 1 day 2 hour | - - - | IGOS 2007 | 2007-11-01 | SAR, SLAR, scatterometer visible/IR SAR, SLAR, scatterometer visible/IR SAR, SLAR, scatterometer visible/IR | |
| Permafrost thermal state | Permafrost | IGOS | -20°C -20°C -20°C | 0°C 0°C 0°C | .05 K .01 K .01 K | Vertical Profile Vertical Profile Vertical Profile | 1 year 1 year 1 year | - - - | IGOS 2007 | 2007-11-01 | Key parameter in the GTN-P; in situ measurements; (annual upper 20-100 m; deeper 5 a) Key parameter in the GTN-P; in situ measurements; (annual upper 20-100 m; deeper 5 a) Key parameter in the GTN-P; in situ measurements; (annual upper 20-100 m; deeper 5 a) | |
| Permafrost thickness | Permafrost | IGOS | 0m 0m 0m | 1600 m 1600 m 1600 m | 1 m 0.5 m 0.5 m | Point Point Point | 10-100 year 10 year 10 year | - - - | IGOS 2007 | 2007-11-01 | Measured or interpolated from temperature profiles; inferred from geophysical logs or surface surveys; modeled parameter Measured or interpolated from temperature profiles; inferred from geophysical logs or surface surveys; modeled parameter Measured or interpolated from temperature profiles; inferred from geophysical logs or surface surveys; modeled parameter | |
| Permafrost distribution | Permafrost | IGOS | Continental | 0% 0% 0% | 100% 100% 100% | - 2% 1% | 10 km 1 km 1 km | 10 year 10 year 1 year | - - - | IGOS 2007 | 2007-11-01 | Inferred from ground temperatures, photo terrain, interpretation, geophysics Inferred from ground temperatures, photo terrain, interpretation, geophysics Inferred from ground temperatures, photo terrain, interpretation, geophysics |
| Permafrost distribution | Permafrost | IGOS | Mountainous | 0% 0% 0% | 100% 100% 100% | - 2% 1% | 25 m 25 m 25 m | 1 year 1 year 1 year | - - - | IGOS 2007 | 2007-11-01 | Distributed models, based on DEM, calibrated with BTS; distribution based on elevation (m) Distributed models, based on DEM, calibrated with BTS; distribution based on elevation (m) Distributed models, based on DEM, calibrated with BTS; distribution based on elevation (m) |
| Downslope creeping velocity | Permafrost | IGOS | 0.01 m/yr 0.01 m/yr 0.01 m/yr | 15 m/yr 15 m/yr 15 m/yr | 1 cm 1 cm 1 cm | Point 10 m 10 m | 1 year 1 year 1 year | - - - | IGOS 2007 | 2007-11-01 | Survey transects, repeat high-resolution imagery, radar, InSAR Same; InSAR Same; InSAR | |
| Annual surface elevation change | Permafrost | IGOS | 0 m 0 m 0 m | 1 m 1 m 1 m | 1 cm 1 cm 1 cm | Point 10 m 1 m | 1 year 1 year 1 year | - - - | IGOS 2007 | 2007-11-01 | In situ survey transects, LIDAR maps, InSAR In situ survey transects, LIDAR maps, InSAR In situ survey transects, LIDAR maps, InSAR | |
| Ground ice volume | Permafrost | IGOS | 0 Vol % 0 Vol % 0 Vol % | 100 Vol % 100 Vol % 100 Vol % | 5-10 Vol % 5 Vol % 5 Vol % | Point 1 m 0.1 m | One time - - | - - - | IGOS 2007 | 2007-11-01 | In situ measurements (sampling during borehole drilling) In situ measurements (sampling during borehole drilling) Geophysical investigations | |
| Active layer depth | Permafrost | IGOS | Area underlain by permafrost | 0m 0m 0m | 5 m 5 m 5 m | 1 cm 1 cm 1 cm | Point Point Point | 1 year 7 day 7 day | - - - | IGOS 2007 | 2007-11-01 | In situ measurements (maximum value at end of summer, key GTN-P parameter) In situ measurements (maximum value at end of summer, key GTN-P parameter) In situ measurements (maximum value at end of summer, key GTN-P parameter) |
| Soil temperature | Permafrost | IGOS | Area underlain by permafrost | -60°C -60°C -60°C | 35°C 35°C 35°C | 0.1 K 0.05 K 0.05 K | Vertical Profile Vertical Profile Vertical Profile | 1 day 6 hour 6 hour | - - - | IGOS 2007 | 2007-11-01 | 10 cm interval to 1.2m on data recorder; GTOS TEM parameter 10 cm interval to 1.2m on data recorder; GTOS TEM parameter 10 cm interval to 1.2m on data recorder; GTOS TEM parameter |
| Surface temperature | Permafrost | IGOS | Area underlain by permafrost | -70°C -70°C -70°C | 45°C 45°C 45°C | 1 K 1 K 1 K | 1 km 100 m 10 m | 1 day 1 day 0.5 day | - - - | IGOS 2007 | 2007-11-01 | MODIS |
| Soil moisture | Permafrost | IGOS | Area underlain by permafrost | 0 Vol % 0 Vol % 0 Vol % | - - - | 1-5 Vol % 1-5 Vol % 1-5 Vol % | Point 1 m 0.1 m | 1 day - - | - - - | IGOS 2007 | 2007-11-01 | Monitored continuously at some locations, or based on sampling during drilling or soil pits; GTOS TEM parameter Same; SAR Same; SAR |
| Duration of thaw | Permafrost | IGOS | Area underlain by permafrost | 0 days 0 days 0 days | 365 days 365 days 365 days | 14 d 7 d 7 d | Point 1 km 100 m | 1 day - - | - - - | IGOS 2007 | 2007-11-01 | Computed from weather records and inferred or measured from soil temperatures; sequential microwave Computed from weather records and inferred or measured from soil temperatures; sequential microwave Computed from weather records and inferred or measured from soil temperatures; sequential microwave |
| Seasonal frost heave / thaw subsidence | Permafrost | IGOS | Area underlain by permafrost | 0 cm 0 cm 0 cm | 100 cm 100 cm 100 cm | 1 cm 1 cm 1 cm | Point 10 cm 1 cm | 0.5 year - - | - - - | IGOS 2007 | 2007-11-01 | In situ survey transects, LIDAR maps, InSAR In situ survey transects, LIDAR maps, InSAR In situ survey transects, LIDAR maps, InSAR |
| Onset of seasonal freezing | Permafrost | IGOS | Areas not underlain by permafrost and beyond limits of permafrost | 0 days 0 days 0 days | 365 days 365 days 365 days | 14 d 7 d 7 d | Point 1 km 100 m | 14 day 7 day 7 day | - - - | IGOS 2007 | 2007-11-01 | Determined from interpolation of soil temperature profiles or frost tubes; passive microwave Determined from interpolation of soil temperature profiles or frost tubes; passive microwave Determined from interpolation of soil temperature profiles or frost tubes; passive microwave |
| Depth of seasonal freezing | Permafrost | IGOS | Areas not underlain by permafrost and beyond limits of permafrost | 0 m 0 m 0 m | 4 m 4 m 4 m | 1 cm 1 cm 1 cm | Point Point Point | 1 year 7 day 7 day | - - - | IGOS 2007 | 2007-11-01 | Determined from interpolation of soil temperature profiles or frost tubes; passive microwave Determined from interpolation of soil temperature profiles or frost tubes; passive microwave Determined from interpolation of soil temperature profiles or frost tubes; passive microwave |
| Duration of freeze | Permafrost | IGOS | Areas not underlain by permafrost and beyond limits of permafrost | 0 days 0 days 0 days | 365 days 365 days 365 days | 14 d 7 d 7 d | Point 1 km 100 m | 1 day - - | - - - | IGOS 2007 | 2007-11-01 | Computed from weather records and inferred or measured from soil temperatures; sequential microwave Computed from weather records and inferred or measured from soil temperatures; sequential microwave Computed from weather records and inferred or measured from soil temperatures; sequential microwave |
| Distribution of seasonal freezing | Permafrost | IGOS | Areas not underlain by permafrost and beyond limits of permafrost | 0% 0% 0% | 100% 100% 100% | % % % | 25 km 10 km 1 km | 5 day - - | - - - | IGOS 2007 | 2007-11-01 | Microwave (passive and active) sensors at regional scales; sequential Microwave (passive and active) sensors at regional scales; sequential Microwave (passive and active) sensors at regional scales; sequential |
| Coastal retreat | Permafrost | IGOS | 0 m/yr 0 m/yr 0 m/yr | 30 m/yr 30 m/yr 30 m/yr | 0.5 m/yr 0.25 m/yr 0.25 m/yr | Point 0.25 m 0.25 m | 1 year - - | - - - | IGOS 2007 | 2007-11-01 | Ground surveys, DGPS, aerial photos, high resolution satellite Ground surveys, DGPS, aerial photos, high resolution satellite Ground surveys, DGPS, aerial photos, high resolution satellite | |
| Isostatic vertical motion | Permafrost | IGOS | 0 cm/yr 0 cm/yr 0 cm/yr | 15 cm/yr 15 cm/yr 15 cm/yr | 1 mm 1 mm 1 mm | Point 1 km 1 km | 1 year - - | - - - | IGOS 2007 | 2007-11-01 | DGPS DGPS, LIDAR, Laser Altimetry DGPS, LIDAR, Laser Altimetry | |
| Wind speed and direction | Permafrost | IGOS | 0 m/s 0 m/s 0 m/s | - - - | 0.1 m/s 0.1 m/s 0.1 m/s | Point Point Point | 1 min - - | - - - | IGOS 2007 | 2007-11-01 | Anemometer Anemometer Anemometer | |
| Storm surge | Permafrost | IGOS | NA - - | NA - - | NA - - | NA 25 m 25 m | NA 1 day 1 hour | - - - | IGOS 2007 | 2007-11-01 | NA Time-lapse camera, tide guage, Opportunistic SAR Time-lapse camera, tide guage, Opportunistic SAR | |
| Sediment transport | Permafrost | IGOS | NA - - | NA - - | NA - - | NA 250 m 250 m | NA 7 day 1 day | - - - | IGOS 2007 | 2007-11-01 | NA MODIS MODIS | |
| Ice scouring depth | Permafrost | IGOS | - - - | - - - | 10 cm 10 cm 10 cm | - - - | - - - | - - - | IGOS 2007 | 2007-11-01 | Multi-beam sonar Multi-beam sonar Multi-beam sonar | |
| Ice scouring area | Permafrost | IGOS | 0% 0% 0% | 100% 100% 100% | 20% 10% 10% | 10 m 1 m 1 m | - - - | - - - | IGOS 2007 | 2007-11-01 | Multi-beam sonar Multi-beam sonar Multi-beam sonar | |
| Subsea permafrost distribution | Permafrost | IGOS | 0% 0% 0% | 100% 100% 100% | % % % | 10 km 1 km 1 km | 10 year 10 year 1 year | - - - | IGOS 2007 | 2007-11-01 | Boreholes, multibeam sonar, shallow seismic Boreholes, multibeam sonar, shallow seismic Boreholes, multibeam sonar, shallow seismic | |
| Subsea permafrost thickness | Permafrost | IGOS | 0 m 0 m 0 m | 500 m 500 m 500 m | 1 m 1 m 1 m | Point Point Point | 10-100 year 10 year 10 year | - - - | IGOS 2007 | 2007-11-01 | Boreholes, multibeam sonar, shallow seismic Boreholes, multibeam sonar, shallow seismic Boreholes, multibeam sonar, shallow seismic | |
| Snowfall amount | Precipitation | IGOS | 0 mm 0 mm 0 mm | 100 mm 100 mm 100 mm | 1 mm 1 mm 1 mm | 1 km 0.5 km 0.1 km | 1 day 1 day 12 hour | - - - | IGOS 2007 | 2007-11-01 | MODIS / SSMI Hydromet Hydromet | |
| Precipitation / Snowfall rate | Precipitation | IGOS | 0 mm 0 mm 0 mm | 100 mm/hr 100 mm/hr 100 mm/hr | 2-10 cm 3 cm 2 cm | 25 km 0.5 km 0.1 km | 1 day 1 day 12 hour | - - - | IGOS 2007 | 2007-11-01 | AMSR-E / TRMM Hydromet Transportation Hydromet Transportation | |
| Precipitation type | Precipitation | IGOS | NA 0.3 0.3 | --- 3 3 | --- 10% 7% | --- 0.5 km 0.1 km | --- 1 day 12 hour | - - - | IGOS 2007 | 2007-11-01 | Need HF SAR Hydromet Hydromet | |
| Snow particle size | Precipitation | IGOS | 0 0 0 | ~0.7 1 1 | 12936 10 6 | 25 km 0.5 km 0.1 km | 1 day 1 day 1 hour | - - - | IGOS 2007 | 2007-11-01 | e.g. AMSR-E Hydromet | |
| Snow/ice albedo | Snow | IGOS | Broadband | 30% 0% 0% | 100% 100% 100% | 7% 1% 0.50% | 1 km 8 km 5 km | 1 day 1 hour 30 minute | - - - | IGOS 2007 | 2007-11-01 | e.g MODIS Hydromet Hydromet |
| Snow/Ice surface temperature | Surface Temp / Albedo | IGOS | 190 K 200 K 200 K | 290 K 275 K 275 K | 2-3 K 1 K 0.1 K | 1 km 1 km 0.1 km | 100 min 1 hour 30 min | - - - | IGOS 2007 | 2007-11-01 | Hydromet Hydromet |
