In 2018, severalheat waves with temperatures far above the long-time average and droughts were recorded in theNorthern Hemisphere:[1] The earth's average surface temperature in 2018 was the fourth highest in the 140 years of record keeping.[2] It is assumed that thejet stream is slowing down, trapping cloudless, windless and extremely hot regions ofhigh pressure. The jet stream anomalies could be caused bypolar amplification, one of the observed effects ofglobal warming.[3][4]
According to theWorld Meteorological Organization, the severe heat waves across the Northern Hemisphere in the summer of 2018, are linked toclimate change, as well as events of extreme precipitation. The results were an increase in mortality of the elderly, severe declines incrop yields, as well as the biggestalgae bloom in theBaltic Sea in decades. This poisoned water both for human and animal use. Additionally,nuclear power plants inEurope were having issues, because the water in the rivers used for cooling thereactors was too warm. This had the effect ofelectricity grids crashing in areas on four continents. The impacts were severe, even in some countries that are considered well prepared to deal with the impacts of climate change.[5][6]
This heatwave across much of the northern hemisphere could continue for weeks, and possibly even months. Accelerated warming in the Arctic compared to the rest of the planet could be a key contributor. The heatwaves have killed dozens in Japan and Korea, have triggered wildfires in California and Sweden, and have led to prolonged dry weather in the UK and across northern Europe, raising temperatures beyond 30°C in Scandinavian sectors of the Arctic Circle. In Greece, the deadliest wildfires in more than a decade have claimed at least 74 lives. "It could persist for weeks, potentially for months," a spokesperson for the UK Meteorological Office told New Scientist.
The rapid retreat of Arctic sea ice caused by climate change may be to blame for more frequent prolonged spells of extreme weather in Europe, Asia and North America, such as heat waves, freezing temperatures or storms. ... They are related to "stuck" weather patterns, Jennifer Francis of Rutgers University in New Brunswick, New Jersey, told a conference on Arctic sea ice reduction in London on 23 September. "Is it global warming? I think it's safe to answer yes," she told the meeting.