Air temperature changes until now

The climate in Luxemburg can be characterized as a moderate oceanic Western European climatewith mild winters and comfortable summers. Lowest long-term mean values occur during January (0.0°C) and highest air temperature occurs in July (16.9°C). Absolute minimum and maximum air temperatures in the reference period 1961-1990 reach from –17.8°C in January (1979) to 35.1°C in July (1964) (1).

Overall annual mean air temperature for Luxemburg-City has increased by 0.5°C per decade between 1971 and 2000 (3).

From 1990 onwards, annual mean air temperatures for the city of Luxemburg started to increase rather sharply to systematically be over the 1961-1990 mean value. Luxemburg-City temperature highs have mostly been observed since 1995. Further analysis of the data suggests that the average air temperature in Luxemburg has increased during the winter seasons, coupled with longer frost-free periods (1).

Precipitation changes until now

With regard to annual precipitation, no clear changes can be detected from the direct measurements. An increase in westerly atmospheric fluxes during winter months has reportedly been responsible over the past 30 years for significant redistributions of winter rainfall totals (1). In combination with higher air temperatures, this has led to higher flood frequencies in most national river basins (2).

Hailstorms

Hailstorms have the potential to cause substantial damage to hail-susceptible objects such as buildings, crops or automobiles. Prominent examples are the two hailstorms related to the low-pressure system Andreas that occurred on 27- 28 July 2013 over central and southern Germany with total economic losses estimated at approximately EUR 3.6 billion (5). There is no good overview of hail events in Europe, however. Little is known about local hail probability and related hail risk across Europe. The majority of Europe is not covered by a hail network, and this leads to a gap in direct hail observations (4).

For a large part of Western Europe, covering Germany, France, Belgium and Luxembourg, the occurrence of hailstorms was mapped over a 10-year period (2005–2014) (4). The results show a sea-to-continent gradient in the number of hail days per year: an increasing gradient in the number of hail days per year can be recognized from north-western France towards central France, and from northern towards southern Germany. The highest number of severe storms is found on the leeward side of low mountain ranges such as the Massif Central in France and the Swabian Jura in southwest Germany. In this study area and study period, hail day frequency was low over north-western France, Belgium and northern Germany.

Air temperature changes in the 21st century

Annual mean temperatures for Luxemburg-City were around 9°C over the period 1971-2000. Mean annual temperatures are expected to reach up to 11.6°C for the period 2071 till 2100 (1).

Precipitation changes in the 21st century

Preliminarily results concerning changes in precipitation suggest a relative stability in annual totals until 2100. However, a substantial redistribution of seasonal precipitation totals can be expected in the second half of the 21st century, with a decrease in summer rainfall and an increase in winter precipitation (1,3).

References

The references below are cited in full in a separate map 'References'. Please click here if you are looking for the full references for Luxemburg.

1. Ministry of Sustainable Development and Infrastructures of Luxembourg – Department of the Environment (2010)
2. Pfister et al. (2000) and (2004), both in: Ministry of Sustainable Development and Infrastructures of Luxembourg – Department of the Environment (2010)
3. Goergen et al. (2013)
4. Fluck et al. (2021)
5. SwissRe (2014); Kunz et al. (2018), both in: Fluck et al. (2021)