Climate change and Covid-19 related shutdown in China

Scientists find out that there is a sudden and fast drop in emissions because of Covid-19. This sudden decline in greenhouse gases has probably played a major role in record rainfall in Mainland China back in 2020, when the pandemic has started. 

Hundreds of people died and millions more were evacuated during a summer of record rainfall, however, long-term cuts in emissions are unlikely to trigger similar events.

The decline in greenhouse gases and small particles called aerosols caused atmospheric changes that intensified the downpours two years ago. Different eastern regions in China experienced severe flooding in June and July.  Scientists believe that the reductions in emissions contributed to the extreme summer rain.

The Yangtze river saw the heaviest rainfall since 1961. There was a 79% increase in June and July in contrast to the average for the period over the last four decades. 

Some scientific studies were pointing to the extreme conditions in the Indian Ocean. A few days ago, an international team has publicly talked about a brand new scientific theory, stating that the abrupt reduction in emissions of greenhouse gases and aerosols, caused by shutdowns during the Covid-19 pandemic, was a key cause of the intense downpours. The authors say that over the past four decades summer rainfall over eastern and central China has decreased significantly due to the increase in the number of aerosols in the atmosphere.

These particles, often associated with the burning of coal, can reduce the occurrence of large-scale storms which resulted in lower rainfall. This new research shows that the absence of these particles, and lower greenhouse gas emissions two years ago had a direct effect on the abrupt climate changes and caused a significantly high percentage of rain.

“There was heating over land due to aerosol reductions but also cooling over the ocean due to a decrease in greenhouse gases, which intensified the land/sea temperature difference in the summer,” explained lead author Prof Yang Yang from Nanjing University of Information Science and Technology, in China.