Extreme weather is the "new norm"

Source: World Meterological Organization

From mountain tops to ocean depths, the summer of extremes continues. Heatwaves are baking large parts of the northern hemisphere, fuelling unprecedented wildfires and disrupting marine ecosystems. Floods have transformed desert landscapes. The high-impact weather in August follows the hottest ever month on record in July.

"This is the new normal and does not come as a surprise," said Alvaro Silva, a climate expert with WMO. "The frequency and intensity of many extremes, such as heatwaves and heavy precipitation, have increased in recent decades. There is high confidence that human induced climate change from greenhouse emissions, is the main driver. This gives us the long-term context for the increasing occurrence and severity of such extreme weather and extreme events," he told a regular media briefing in Geneva.

He said that the behaviour of the jet stream was also a contributing factor - its position has sometimes been. more southern than usual and has been meandering in some regions generating blocking (persistent weather pattern) conducive of extreme weather events such as heatwaves as warmer air is pulled from subtropical regions.

"There are several studies suggesting a connection between rapid warming and changes in the Arctic, due to human-induced climate change, and midlatitude weather patterns, including in atmospheric dynamics such as the jet stream but further in depth research is needed to fully understand and explain the extremes occurring this summer," said Mr Silva.