In early April 2021, several days of severe frost affected central Europe following an anomalously warm March. This led to severe damages in grapevine and fruit trees, particularly in France and Balkan region, where young leaves had already unfolded in the warm early spring. The mild early days of April 2021 were interrupted by a polar air mass that spread in a strong jet stream from Northern to Central Europe on Monday 5th of April 2021, reached Slovenia on Tuesday 6th of April 2021 and then passed the Balkan, moving towards Greece and Turkey. After the cold front passed Europe, an anticyclone formed on the 6th of April 2021. The clear skies in combination with the dry arctic air mass and fresh snow on the ground caused the morning of April 7th to be the coldest day of April in many parts of Slovenia in the last 60 years. The lowest temperature measured was -20.6 °C at the location Bloke, Nova vas, Slovenia.
The information on solar radiation is important not only in climatological and meteorological models, but also in the energy sector and agriculture. Since 2005 the downwelling surface short-wave radiation flux (DSSF) is operationally available from two products based on MSG/SEVIRI: the MSG Downward Shortwave Surface flux (MDSSF, LSA-201) provides estimates every 30 minutes, while the Daily Downward Surface Shortwave Flux (DIDSSF, LSA-203) provides daily integrals of the DSSF. In the last years a new product was developed, the MSG Total and Diffuse Downward Surface Shortwave Flux (MDSSFTD, LSA-207).
In recent years, severe weather regimes in European countries are becoming more and more frequent and intense. Areas located mostly in Southern Europe experienced extreme weather events during the summertime, such as droughts and heat waves. These events strongly affect vegetation and can even result in wildfires, turning the green, healthy areas into less fertile land. Reduced productivity of vegetation can also be a consequence of other factors such as pests and other natural hazards that affect the growth rate.
Evapotranspiration plays a crucial role in the recycling of precipitation, in soil water availability and consequently on food production. It depends mainly on the solar energy available to vaporize the water, on water content in the soil layers and on land cover types (like vegetation, open water, bare soil, etc.).
Fraction of vegetation cover (FVC, LSA-421; https://landsaf.ipma.pt/en/products/vegetation/fvc/) is a vegetation product based on multi-channel remote sensing measurements derived from Meteosat geostationary satellite. It gives information on the fraction of ground unit area covered by green vegetation, which is relevant for applications in agriculture, forestry, environmental management and land use. It has also proved to be useful for drought monitoring.
Monitoring of Vegetation Condition
Example of drought detection by combining precipitation, vegetation indices and satellite derived evapotranspiration
Drought is a recurring climate feature that results from water deficit (precipitation, surface water or groundwater) over an extended period. Meteorological drought usually precedes other types of droughts and occurs when there is a prolonged time with less than average precipitation. Agricultural drought develops when meteorological drought leads...
Vegetation Response Variability from Meteosat
How do land and climate type as well as irrigation affect vegetation signal from space?
Fraction of vegetation cover (FVC) represents the fraction of green vegetation covering a unit area of horizontal soil. Vegetation signal from space depends on various factors, such as growing season, water availability and vegetation type. Yearly evolution of LSA SAF FVC from the Meteosat satellite...
Satellite Derived Evapotranspiration is Advantageous for Drought Detection
Analysing Drought Impact by Combining Evapotranspiration and Vegetation Signal
A combination of satellite derived evapotranspiration and vegetation signal improves locating and analysing drought affected areas. In the scope of drought monitoring, satellite vegetation signal, e.g., fraction of vegetation cover is a very reliable indicator of vegetation health....
The Nile valley and delta are among the first places where agriculture and civilisation came into existence. The Nile water flow with the largest inflow in the summer, because of the rainy season in the Ethiopian Highlands, supports irrigation in an otherwise very barren region (away from the Mediterranean coast the interior of Egypt has one of the driest climates in the world with precipitation barely above zero).
A prolonged period of warmer-than-average weather over Europe in March and first half of April 2017 came to a halt after polar air mass rapidly moved southwards from N/NE of the continent. This event resulted in one of the worst frost damage in recent years. It affected vegetation, which was already in bloom over larger areas of Central, Western and Eastern Europe. Particularly hard-hit were areas with fruit cultivation, e.g., apples, grapes, pears and cherries...
Fraction of vegetation cover (FVC) represents the fraction of green vegetation covering a unit area and is very helpful for monitoring the current state of vegetation. LSA SAF FVC over Europe in summer 2017 is shown together with differences from the reference state of vegetation over the same summer period...