| Accumulated precipitation | 2 - very high | Poor time sampling.. Time sampling to be interpolated by GEO. | MW channels around 10, 19, 23, 37 and 90 GHz and in 54 GHz band, with high spatial resolution |
| Atmospheric temperature | 3 - high | Very coarse vertical resolution. | 54 GHz band. Nearly all-weather sounding |
| Biomass | 3 - high | Index only.. Coarse spatial resolution. | Derived from differential effect of vegetation across MW frequencies around 7, 10 and 19 GHz |
| Cloud liquid water (CLW) | 3 - high | No specific limitation. | MW channels around 37 and 90 GHz |
| Cloud liquid water (CLW) total column | 3 - high | No specific limitation. | MW channels around 37 and 90 GHz |
| Freezing level height in clouds | 4 - fair | No specific limitation. | MW channels in the 54 GHz band. Inference from the temperature profile |
| Land surface temperature | 5 - marginal | Coarse spatial resolution. | MW channels around 7 and 10 GHz |
| Long-wave Earth surface emissivity | 3 - high | Long time series needed. | MW channels around 7, 10, 19, 37 and 90 GHz. Emissivity across this MW range inferred by statistical analysis |
| Melting layer depth in clouds | 4 - fair | No specific limitation. | MW channels in the 54 GHz band. Inference from the temperature profile |
| Precipitation intensity at surface (liquid or solid)* | 2 - very high | No specific limitation. | MW channels around 10, 19, 23, 37 and 90 GHz, and in 54 GHz band (for atmospheric temperature). To cover sea and land, heavy and light precipitation. High spatial resolution consistent with the scale of precipitation |
| Sea surface temperature* | 3 - high | No specific limitation. | MW channels around 7 and 10 GHz |
| Sea-ice cover* | 1 - primary | No specific limitation. | MW channels around 7, 10, 19, 37 and 90 GHz, with high spatial resolution for accurate contour detection |
| Sea-ice type | 4 - fair | No specific limitation. | MW channels around 7, 10, 19, 37 and 90 GHz. Type interpreted as age/roughness |
| Snow cover | 2 - very high | Coarse spatial resolution. | MW channels around 19, 37 and 90 GHz. Higher frequencies less sensitive to emissivity from ground under snow . High resolution closer to the scale of snow fields |
| Snow status (wet/dry) | 1 - primary | Coarse spatial resolution. | MW channels around 19, 37 and 90 GHz. Higher frequencies less sensitive to emissivity from ground under snow. High resolution closer to the scale of snow fields |
| Snow water equivalent | 1 - primary | Coarse spatial resolution.. Ground stations network needed. | MW channels around 19, 37 and 90 GHz. Higher frequencies less sensitive to emissivity from ground under snow. High resolution closer to the scale of snow fields |
| Soil moisture (in the roots region) | 4 - fair | Coarse spatial resolution.. Affected by vegetation. | MW channels around 7 GHz. Assimilation process required |
| Soil moisture at surface | 3 - high | Coarse spatial resolution.. Affected by vegetation. | MW channels around 7 and 10 GHz |
| Integrated Water Vapour (IWV) | 1 - primary | No specific limitation. | Use of water vapour band around 23 GHz with dual polarisation. High resolution useful for tomography |
| Wind speed (near surface)* | 2 - very high | Over sea only. | MW channels around 7, 10, 19 and 37 GHz |
Instrument: AMSR