Surface observations

Surface in-situ data provide information often with high precision and time resolution. Even in the satellite era, surface observations contain essential information that cannot be provided by other platforms.

Long records of surface observations, going back to the mid-19th century and before, provide invaluable information on the history of European climate. They are required to place extreme events with large impacts in a historical perspective.

In the implementation plan of the Global Climate Observing System (GCOS), a number of Essential Climate Variables (ECVs) were defined for the atmospheric, oceanic and terrestrial domains. EURO4M considers those ECVs that form primary input to the GMES services and the societal benefit areas defined by the Group on Earth Observations (GEO).

The atmospheric in-situ variables EURO4M focuses on are: air temperature, sea surface temperature, precipitation, snow cover, air pressure, surface radiation budget, wind speed and direction and water vapour. Issues such as data archaeology, homogeneity of the records and spatial interpolation are addressed within the project in order to make reliable and state-of-the-art high-resolution analyses for Europe.

Number of frost days in January 2009
A particularly cold spell over Western Europe occurred in the winter of 2008/2009. This figure shows the number of frost days in January 2009, where the minimum temperature is below 0 C. Large parts of Central and Western Europe show 10 more frost days in January 2009 compared to the long term average. (Source: ECA&D)