研究显示北极极端天气事件近几十年显著增多

Core Insights - An international study led by the Finnish Meteorological Institute indicates a significant increase in various extreme weather events in the Arctic over recent decades, suggesting that the Arctic terrestrial ecosystem is increasingly exposed to unprecedented climate conditions, which may have profound impacts on the local natural environment [1][2] Group 1: Extreme Weather Events - The study highlights that the Arctic is warming at a rate approximately three to four times faster than the global average, leading to an overall increase in the frequency and intensity of extreme phenomena such as prolonged heatwaves, frost during the growing season, unusually warm winters, and "rain on snow" events [1] - A notable new extreme weather event identified is "rain on snow," which occurs when rain falls on snow during the snow season, affecting over 10% of the Arctic land area [1] Group 2: Ecological Impact - The occurrence of "rain on snow" can create ice layers within the snowpack, making it more difficult for certain mammals, such as reindeer, to access vital winter food sources like lichen [1] - The study also identifies significant "hotspot" areas in the Arctic where seasonal conditions and extreme weather events have changed notably, primarily located in western Scandinavia, the Canadian Arctic Archipelago, and central Siberia [2]