Sizzling Hot Duisburg: Explaining Germany's Sweltering Heat Capital
In the heart of North Rhine-Westphalia, Duisburg has been making headlines as one of the hottest places in Germany. On July 1, the city was ranked second in DTN's "Hitlist Germany" with a scorching 37.9 degrees, and just a day later, the German Weather Service (DWD) measured a staggering 38.3 degrees in Duisburg-Baerl.
The geographical location and topography of Duisburg play a significant role in the high temperatures. Nestled in the west German lowlands, the city is situated in a triangle between the Cologne Bay, Lower Rhine, and western Ruhr area, making it one of the lowest areas in North Rhine-Westphalia. This location allows hot air masses from Africa and Spain to flow unimpeded into the west of the region.
However, it's not just the geography that's driving the heat. The urban heat island (UHI) effect is a major contributor to the extreme temperatures in Duisburg. The UHI effect causes urban areas to be significantly warmer than their rural surroundings, and Duisburg is no exception.
The city's urban density and infrastructure are key factors in the UHI effect. With a high concentration of buildings, paved surfaces, and industrial facilities, Duisburg absorbs and retains heat during the day, releasing it slowly at night, elevating local temperatures compared to greener, less developed areas.
Industrial activity also plays a significant role. The city's industrial operations generate waste heat and contribute to localized warming, further intensifying the heat that accumulates in the urban environment, particularly during heatwaves.
Climate change is exacerbating the UHI effect by increasing baseline temperatures. Recent heat records, such as the 41.2°C recorded in Duisburg-Baerl in July 2019, illustrate how global warming makes heatwaves more intense and frequent across Europe, including Germany.
Lack of cooling green spaces is another factor. Urban areas like Duisburg often have fewer trees, parks, and water bodies that naturally cool the environment via shade and evapotranspiration. This absence limits opportunities to moderate temperatures within the city.
In addition, the DWD explains that an additional burden due to reduced nocturnal cooling is expected in Duisburg's densely built-up area. The city's urban layout, intense industrial activity, and heating of built environments combined with the broader impact of climate change contribute to its higher temperatures relative to other parts of Germany.
Duisburg's status as Europe's largest steel site further contributes to the heat. The city's industrial operations generate significant amounts of heat, adding to the urban heat island effect.
The perceived temperature in Duisburg was given as up to 46 degrees by the service Wetterkontor on Wednesday. Despite the heat, Duisburg continues to battle the urban heat island effect, with efforts underway to increase green spaces and improve urban planning to mitigate the effects of the UHI.
[1] Source: DTN, DWD, and Kesseler-Lauterkorn.
Science and environmental science are crucial in understanding why Duisburg, a city in North Rhine-Westphalia, has been experiencing exceptionally high temperatures. The urban heat island effect, driven by the city's urban density, infrastructure, industrial activity, and climate change, contributes significantly to these heatwaves. Furthermore, the lack of cooling green spaces exacerbates the problem, making it essential to focus on increasing urban green spaces to combat the urban heat island effect.
