German Weather Service - Last twelve months wetter than ever since measurements began
No English record for temperature was broken in the past twelve months as it has never been this warm. The German Weather Service (DWD) reports a new record: In the past twelve months, it has rained more here than ever before. Since 1881, there has been no twelve-month period in Germany as rainy as the one from July 2023 to June 2024.
German Weather Service: Moisture ends dry phase
However, no single month was exceptionally rainy, explains the head of Hydrology at the DWD, Frank Kaspar. The record is only an average. In total, over Germany, around 1,070 liters per square meter fell in this period. In comparison, the long-term average of the reference period 1961-1990 is approximately 789 liters per square meter per year.
A look into the national climate archive of the DWD shows: In the past ten years, below-average annual precipitation sums have been observed. However, precipitation generally "has a high variability," according to the hydrometeorologist. The dryness of the past years was now replaced by a very wet twelve-month period.
Climate change fuels moist extreme weather events
A possible reason could be global warming. Due to rising temperatures, more water evaporates from the ground and bodies of water. This increases the water vapor content in the air, which in turn strengthens the greenhouse effect. According to NASA, the water vapor content in the atmosphere increases by seven percent for each degree Celsius temperature rise. Other studies calculate an increase of one percent per decade. Depending on the model, the water vapor content has increased by up to four percent since 1990. However, the distribution is not evenly spread over the planet.
Warmer air can also absorb more moisture than cold air. In principle, moisture in the atmosphere provides ideal conditions for summer thunderstorms and storms. If the global temperature continues to rise, so will the water vapor content. The result: Storms will become more intense.
The new record of rainfall in Germany, as reported by the German Weather Service (DWD), exceeds the long-term average of the reference period by around 281 liters per square meter for each year. This heavy rainfall in Germany during the period of July 2023 to June 2024 broke previous records, making it the rainiest twelve-month period since the establishment of DWD in 1881.
