Why is the weather so hot?

Monitoring from the National Climate Center shows that since June 13, a regional high-temperature weather process has occurred in our country, which is wide in scope, long in duration, highly extreme, and has a large impact. As of July 12, the high temperature event has lasted for 30 days, covering a land area of ​​5.021 million square kilometers and affecting a population of more than 900 million people.

Especially since July 7, high temperatures have suddenly emerged in the south. Jiangsu, Zhejiang, and Sichuan and Chongqing have become the national high temperature centers. High temperatures above 40°C have occurred in many places, and historical high temperature records have been frequently broken.

High temperature weather has recently occurred not only in China, but also in many places in the northern hemisphere.

Fu Jiaolan, chief forecaster of the Central Meteorological Observatory, said that since the beginning of the 21st century, high temperature and heat wave events have become increasingly frequent in the northern hemisphere in summer, and global warming is the root cause of frequent high temperature and heat wave events.

According to monitoring by the National Climate Center of the China Meteorological Administration, in June this year, the global average temperature was about 0.4°C higher than normal, the highest since 1979. Among them, northern Russia, western Europe and other places were 2°C higher. Above, many cities in France, Spain, the United States, Japan and other countries set new high temperature records.

The Sixth Assessment Report of the United Nations Intergovernmental Panel on Climate Change pointed out that in the past 50 years, global warming has occurred at an unprecedented rate since the past 2000, and the instability of the climate system has intensified. United Nations Secretary-General Guth said Reis called it a "red alert for all mankind."

Relevant experts from the National Climate Center said that global warming is the climate background for frequent high-temperature and heat wave events in the northern hemisphere, and abnormal atmospheric circulation is the direct cause of frequent high-temperature and heat waves in many places around the world since June.

Since June this year, over the subtropical regions of the northern hemisphere, the western Pacific subtropical high, Atlantic high and Iranian high have all strengthened in stages, thus forming a large-scale global warm high pressure belt. Downdrafts prevail under the control of warm high-pressure belts, which is conducive to ground warming. In addition, under the influence of large-scale high-pressure belts, the air is drier and less likely to form clouds. It also makes it easier for solar radiation to reach the ground, leading to frequent high temperatures. , and the intensity is relatively strong, resulting in sustained high temperature heat wave events in many places in the northern hemisphere.