Heatwaves are becoming more frequent, intense and prolonged worldwide as a result of climate change and global warming, the World Meteorological Organization (WMO), a UN agency, has warned. According to the organization, as the Earth’s average temperature continues to rise, extreme heat events are not only occurring more often but are also lasting longer and affecting larger areas.
Several parts of Europe are currently experiencing their fifth heatwave of the summer. Severe heat, combined with extreme drought and wildfires in various areas, has worsened the situation. Record temperatures have also been recorded in some locations.
Speaking at a news conference in Geneva, WMO climate data chief John Kennedy said heatwaves are now occurring more frequently than in the past, while their intensity and duration are also increasing. At the same time, these heatwaves are spreading across larger geographical areas. He said the current heatwave in Europe, the world’s fastest-warming continent, is being driven by a combination of atmospheric high-pressure systems and a warmer climate.
High-pressure systems create conditions conducive to rising temperatures. They can trap hot air over a particular region, reduce cloud cover and prevent cooler air from entering. As a result, unusually high temperatures can persist in an area for several days or even weeks.
The WMO said the ongoing European heatwave is not being driven by El Niño. The climate phenomenon normally plays an important role in natural variations in global temperatures. However, conditions in the tropical Pacific Ocean are currently largely neutral.
Comparing the current situation with the past, Kennedy said a similar atmospheric pattern of high- and low-pressure systems occurred in June 1976. However, global warming was less pronounced at that time, resulting in different impacts.
According to Kennedy, above-average temperatures in 1976 were largely confined to several isolated regions. The situation is markedly different today, with temperatures above the average being observed across much of the world. Because of global warming, the same type of weather pattern is now producing far more intense effects.
Unusually warm seas around Europe are also contributing to the severity of the current heatwave. Marine heatwaves in the Mediterranean and seas surrounding western Europe are helping to drive up temperatures over land.
Meanwhile, prolonged periods of below-average rainfall have reduced soil moisture across several parts of Europe. When soil moisture is low, the land heats up more rapidly. This can further increase surface temperatures and allow heatwaves to remain intense for longer periods.
Kennedy said there is no single factor behind the record-breaking temperatures recorded this year. Instead, a combination of natural and climate-related factors has become active at the same time, making the situation more complex and severe.
The WMO’s warning suggests that continued global warming could further alter the pattern of heatwaves in the future. Alongside more frequent episodes of extreme heat, the risk of heatwaves becoming longer-lasting and covering wider areas is also expected to increase.
Source: Reuters.