The following new observations have been activated in the operational ECMWF assimilation systems during October – December 2024.
| Observations | Main impact | Activation date |
|---|---|---|
| SNOTEL snow data | Snow analysis, surface parameters | 8 October 2024 |
| SYNOP/METAR temperature | 2 m temperatures in atmospheric 4D-Var (previously used in the land surface analysis only) | 12 November 2024 |
| Ground-based GNSS stations zenith total delay | Integrated water vapour | 12 November 2024 |
| NOAA-21 VIIRS AMVs | Tropospheric wind at high latitudes | 10 December 2024 |
| PlanetIQ radio occultation bending angles | Temperature and winds in upper troposphere/lower stratosphere | 11 December 2024 |
| Scatterometer winds from HY-2C | Near-surface winds over the ocean | 11 December 2024 |