Des longs (et chauds) étés

Jonathan Watts, The Guardian :

Rising temperatures in the Arctic have slowed the circulation of the jet stream and other giant planetary winds, says the paper, which means high and low pressure fronts are getting stuck and weather is less able to moderate itself.

The authors of the research, published in Nature Communications on Monday, warn this could lead to “very extreme extremes”, which occur when abnormally high temperatures linger for an unusually prolonged period, turning sunny days into heat waves, tinder-dry conditions into wildfires, and rains into floods.

« We show that interactions between Arctic teleconnections and other remote and regional feedback processes could lead to more persistent hot-dry extremes in the mid-latitudes », expliquent les auteurs. « The exact nature of these non-linear interactions is not well quantified », précisent-ils, « but they provide potential high-impact risks for society. »