Annual, summer and winter mean potential evapotranspiration given in respectively mm/year and mm/3 months and based on the Penman-Monteith definition. The potential evapotranspiration fields are available for the present target year 1975, which corresponds to the middle of the 30-year period 1961-1990.

Annual and seasonal precipitation indices given in number of days: 1/ Wet days: Number of days with precipitation > 0.1 mm/day for winter, autumn, spring, summer; 2/ Dry days: Number of days with precipitation < 0.1 mm/day for winter, autumn, spring, summer; 3/ Average length of dry spells: Mean duration of minimum three consecutive days with precipitation < 0.1 mm/day; 4/ Maximum length of dry spells: Longest period of minimum three consecutive days with precipitation < 0.1 mm/day, occurring once in 20 years. The precipitation indices are available for the present target year 1975, which corresponds to the middle of the 30-year period 1961-1990.

Annual temperature extremes given in number of days: 1/ Total number of heatwaves occurring once in 20 years; 2/ Maximum length of the heatwaves occurring once in 20 years; 3/ Hot days: Mean annual number of days with maximum temperature > 25°C; 4/ Tropical days: Mean annual number of days with maximum temperature > 30°C; 5/ Frost days: Mean annual number of days with minimum temperature < 0°C. Heatwaves are defined according to the Royal Meteorological Institute of Belgium when the maximum temperature in Uccle is >= 25°C during at least 5 consecutive days, during which at least 3 days the maximum temperature is >= 30°C. The temperature extremes are available for the present target year 1975, which corresponds to the middle of the 30-year period 1961-1990.

Annual and seasonal precipitation indices given in number of days: 1/ Wet days: Number of days with precipitation > 0.1 mm/day for winter, autumn, spring, summer; 2/ Dry days: Number of days with precipitation < 0.1 mm/day for winter, autumn, spring, summer; 3/ Average length of dry spells: Mean duration of minimum three consecutive days with precipitation < 0.1 mm/day; 4/ Maximum length of dry spells: Longest period of minimum three consecutive days with precipitation < 0.1 mm/day, occurring once in 20 years. The precipitation indices are available for the future target year 2085, which corresponds to the middle of the 30-year period 2071-2100, and for mean and high impact scenarios corresponding respectively to the 50th, and 5th or 95th percentiles of the change factors.

Summer and winter maximum daily precipitation given in mm/day that occur once in a year and once in 5, 10, 15 and 30 years (i.e. return periods of 1 year and 5, 10, 15, 30 years). The precipitation extremes are available for the present target year 1975, which corresponds to the middle of the 30-year period 1961-1990.

This dataset contains the orthophoto mosaics that were created following the floods of July 2021 in the valleys of the Vesdre, the Meuse and the Demer. Orthophotos are aerial photographs that have been geometrically corrected (orthorectified) to eliminate distortions caused by terrain relief, lens distortion, and camera tilt. Unlike raw aerial imagery, orthophotos have a uniform scale and accurate geometry, making them suitable for cartography, measurements, and visual analysis. This specific dataset includes orthophotos based on aerial photographs acquired in July 2021 by Hansa Luftbild, commissioned by the National Geographic Institute (NGI), following the floods in the zones of the Vesdre, a part of the Meuse downstream of Liège and the Demer. The resulting orthophoto mosaics are georeferenced in the Lambert 2008 coordinate system. All orthophotos are in colour (RGB). The ground resolution (GSD) is 6.5 cm (4 cm above the Hoëgne). The spatial coverage of this dataset is limited to the affected zones. The data can be visualized via the corresponding web service (WMS). The data is available on request via https://ngi.be/aanbod/kaarten-en-fotos/luchtfotos-orthofotos/.

The number of private households according to official statistics, per administrative unit (region, province, district and municipality) for Wallonia.

Population density and area of administrative entities (region, province, district and municipality) for Wallonia.

Annual, summer and winter mean potential evapotranspiration given in respectively mm/year and mm/3 months and based on the Penman-Monteith definition. The potential evapotranspiration fields are available for the future target year 2085, which corresponds to the middle of the 30-year period 2071-2100, and for mean and high impact scenarios corresponding respectively to the 50th and 95th percentiles of the change factors.

Annual, seasonal and monthly precipitation amounts given in respectively mm/year, mm/3 months and mm/month. The precipitation amounts are available for the future target year 2085, which corresponds to the middle of the 30-year period 2071-2100, and for mean and high impact scenarios corresponding to respectively the 50th, and 5th or 95th percentiles of the change factors.