Global Climate

Abstract

Throughout 2022, the "triple-dip" La Niña (three consecutive years) showed its hand in a large number of the essential climate variables and metrics that are covered in this chapter. La Niña conditions tend to have a cooling effect on global temperatures in comparison to neutral or El Niño years and impact precipitation patterns around the globe. Upper-level wind patterns at 200 hPa across the globe for 2020-22 showed a striking similarity with the last triple-dip La Niña that occurred in 1998-2000.Yet, despite the cooling effect of the ongoing La Niña, 2022 was still among the six warmest years since global records began in the mid-to-late 1880s, according to six datasets of global surface temperatures. It was also the warmest La Niña year on record, surpassing 2021.Exceptional heatwaves occurred across the globe in 2022, boosted by above-average temperatures that continue their relentless long-term rise. In Europe, the "unweather"-an Old English term for weather so severe that it appears to come from a different climate or world-shattered records across the continent during the summer months, while rivers and reservoirs fell to critically low levels. Meanwhile China experienced its hottest summer on record and at Wuhan, the Yangtze River reached record-low values.The extreme high summer temperatures over Europe resulted in unprecedented melting of glaciers in the Alps, with over 6% of their volume lost in Switzerland this year alone, a record loss. Globally, 2022 was the 35th consecutive year of glacier mass loss and the 14th consecutive year of exceptional loss (more than 500 mm water equivalent). Ice cover on lakes was almost nine days shorter than average, the fourth shortest since 1980; the five shortest ice seasons have all occurred since 2016. The average temperature anomaly for more than 1950 lakes across the Northern Hemisphere was the second highest since the beginning of the record in 1995.Drought conditions were pervasive, occurring across Europe (linked to the extreme summer temperatures), as well as the American West, China, and most of Southern Hemisphere South America. Globally, record-high areas of land experiencing extreme drought (6.2%) were reached in August 2022; overall, 29% of land experienced moderate or worse categories of drought. Low values of terrestrial water storage also occurred in Europe and parts of China (linked to the heatwaves), but La Niña influenced high values in southeastern Australia. Extreme rainfall was observed in southeastern and eastern Australia as well as in Pakistan, which received around three times its normal August monsoon rainfall. However, precipitation amounts for the globe as a whole and over the ocean was much lower than normal, but close to normal over land. Total column water vapor and surface humidity were close to normal over the ocean. Despite 'normal' rainfall amounts over land and lower terrestrial water storage, 2022 saw continued above-average soil moisture values, which are approaching the level of the previous global record in 2011. Lake water l...