Satellite sunshine records

The SAF on Climate Monitoring provides satellite-based climate information on a variety of parameters, which can help people find out something more about the local weather in general.

These include CM SAF products of daylight and surface incoming shortwave radiation derived from MVIRI instrument onboard the Meteosat 1-7 satellites, and fractional cloud cover derived from AVHRR instruments onboard the polar-orbiting satellites (Metop and NOAA).

Data from the summer mean daylight (Figure 3) and solar radiation (Figure 2) over the period 1990-2005 and the summer mean cloudiness (Figure 1) over the period 1982-2009, show that southern Europe on average has the lowest cloudiness, which does not exceed 10–60%. The cloudiest places in Europe are the British Isles and NW Scandinavia, where clouds cover up to 60–90% of the sky.

As cloudiness has a direct impact on the amount of sunshine and solar radiation that reaches the surface, the distribution of the intensity of solar radiation (W/m²) and daylight (kLux) is closely related to cloudiness.

Therefore, the highest intensity of solar radiation (250–350W/m²) and daylight (30–40kLux) can be observed over the Mediterranean. However, in some places in north west Europe the summer mean intensity of solar radiation does not exceed 150–200W/m² and 18–24kLux in the intensity of daylight, which is normal for the Mediterranean in spring and early autumn.

Who uses this information? The CM SAF data is available to users interested in climate monitoring (such as the National Meteorological Services), research, modelling and other activities.

Additional content

Latvian Met Service story on sunshine records (in Latvian)