Lake Constance: temperature shock! Record heat gives way to sudden cooling

Lake Constance: temperature shock! Record heat gives way to sudden cooling

Bodensee, Deutschland - The Lake Constance presents itself in July 2025 with a record of 27 degrees Celsius. But this gratifying state did not last long. After a sudden change in weather and rain showers, the temperature fell again to less than 23 degrees Celsius. Lake Constance describes this as a "cool Alpine margin lake", which represents a striking contrast to the high temperatures of the past few days. Historically, temperatures above 26 degrees in Lake Constance are rather rare, but such extreme values have been increasing steadily in recent years, as [https://www.vol.at/heisse-welle-kalte-dusche-der-bodensee-show---s--a--a--a--a--a--a--a--a--a--a--a--a--a--a--a--a--s--s--s-s--s--s--a--a--a--a--a--s-s--s--s--s--s--s--s--s--s--s--s--s--s--s---a--a--a-

The average water temperature in July of the past two decades was around 23 degrees, but now day agent temperatures between 24 and 26 degrees are no longer uncommon. The trend also shows that the maximum values are exceeded more often in the summer months. This change contributes to an overall perceptible warming of Lake Constance, because the data prove a continuous increase in day agent temperatures in summer since 2015.

Influence of climate change

Lake Constance is increasingly influenced by climate change. According to [research-und-wissen.de] (https://www.forschung-und-wissen.de/nachrichten/umwelt/wasseremperature-des-bodensees-nmt-klimamawandel-stig- zu-13379088), the average surface temperature from 10.5 degrees Celsius in 1962 rose to 13.6 degrees Celsius, with a maximum value of 14.1 degrees Celsius in 2022. These temperature changes are not only statistical data, but also have an immediate impact on the Ecosystem of Lake Constance. Fish have difficulties with reproduction because their food sources change, which leads to a risky imbalance in the food network.

In addition, the temperatures increase in deep water layers, which negatively influences circulation. Less oxygen gets into deeper layers, which increases the risk of lack of oxygen and endangers the water chemistry. Especially the cloudy, an important fish in Lake Constance, suffers from the higher water temperatures that endanger the survival of eggs and larvae. Statistics show that lower fishing numbers are the result.

long -term trends

Model calculations carried out in the “Sea Affairs Climate” project forecast a further increase in the surface water temperature between 1.3 and 2.2 degrees Celsius compared to the period 1981-2010, depending on the underlying climate scenario. This is expected to lead to longer and hotter summers as well as shorter, milder winters. The complete circulation of the water layers becomes less common, which has serious consequences for the quality of water, as well as igkb.org.

The changes in water storage behavior are also worrying. In the past decades, scientists have observed both higher water levels in winter and deeper water levels in summer. These extreme fluctuations are the result of a combination of reduced rainfall, which are stored as snow, as well as changed summer evaporation. Future tendencies could therefore indicate an increasing risk to the entire ecosystem.

Overall, Lake Constance faces challenging ecological changes that result from climate change. These developments affect not only the water temperature, but also the entire biodiversity and quality of life in the region.