Why summer 2022 is so hot both in China and globally? Experts point to La Nina, predict ‘roast mode’ to linger
Published: Aug 13, 2022 08:00 PM
A citizen walks by a fountain amid high temperature in Minhang District of east China's Shanghai, July 10, 2022. Photo:Xinhua

A citizen walks by a fountain amid high temperature in Minhang District of east China's Shanghai, July 10, 2022. Photo:Xinhua

Multiple Chinese provinces and regions continued to endure "roast mode" after 23 consecutive high temperature alerts were issued by the China Meteorological Administration (CMA), which on Friday evening issued the first red heat wave alert, the highest level, for the year of 2022. 

Readings over 40 C, an unimaginable temperature even for summer, has become the new normal this year for Chinese cities. Even 40 C cannot qualify a city to enter the top 10 hottest cities in the country. The threshold for the ranking is as high as 42 C on Saturday, according to CMA data. 

On social media, people complained about skyrocketing power prices for air conditioning and some places, including East China's Anhui Province, have introduced power restrictions for designated industries. Agriculture has also been impacted, as extreme temperatures threaten growth and yields of many economic crops such as tea and oranges. 

Posts of fun pictures on social media show zoos serving iced fruits and water to relieve fur-covered animals from the extreme heat while there have also been multiple reports of outdoor workers dying of heatstroke. 

The Beginning of Autumn, which fell on August 7 this year, failed to deliver lower temperatures. Experts predicted the current heat wave, which started as early as June in some southern provinces, will linger for another one or two weeks, triggering broad public disappointment. 

Chen Lijuan, a weather forecaster from the Beijing Climate Center under the CMA, told media that this year's prolonged heat wave could be the strongest since records were first kept. Another forecaster, Chen Tao, said the high temperatures will continue for another one to two weeks with the lower reaches of the Yangtze and Yellow rivers being hardest hit.

Why this year's heat wave is so long and so strong? Zheng Fei, a research fellow at the Institute of Atmospheric Physics of the Chinese Academy of Sciences, explained the major reason to be the abnormal persistence of an extensive subtropical anticyclone.

The anticyclone system means sinking airflows prevail and cause a significant rise in the near-surface temperatures. The sinking airflows also lead to clear weather with less cloud cover, which increases solar radiation and causes higher temperatures on the ground, Zheng explained. 

The persistence of an anticyclone system has not only affected China but also European countries and American states along similar latitudes, and it is part of a La Nina phenomenon.

Experts noted that with climate change accelerating, extreme weather and abnormal weather systems could become more frequent.