Climate warming is intensifying the frequency and intensity of extreme weather climate events, which is manifested in the warm Arctic cold Eurasian type in winter and the high temperature heat wave in the Eurasian region in summer. On December 23, Ding Yihui, an academician of the Chinese Academy of Engineering, analyzed the relationship and performance between global warming and extreme weather and climate events at the expert innovation lecture jointly hosted by the Ministry of Human Resources and Social Security and the China Meteorological Administration, and said that the world has entered a new normal of climate change, and it is necessary to propose and establish new adaptation strategies and response mechanisms.

Extreme weather climate events and global average temperature are two key physical quantities that are related to each other to determine and quantify the evolution characteristics of global warming, but also represent different characteristics of global warming. Global warming is mainly characterized by the average temperature in different global time ranges, which is the spatio-temporal average of the temperature measurements obtained by all observation stations in a certain period of time, including land and ocean. Extreme weather and climate events represent weather and climate events that significantly deviate from the average climate value and have a very low probability of occurrence, but their intensity or variability is very large, such as rainstorm, flood, high temperature heat wave, etc., which often cause serious meteorological disasters.

Monitoring analysis shows that from 1989 to 2016, the winter temperature in the Arctic rose much faster than the global average temperature, while the winter in Europe and Asia became colder, with frequent strong cooling events. From December 2015 to January 2016, there was sudden warming in the Arctic. In China, the "super cold wave" occurred in the last ten days of January 2016, with the temperature 0 ℃ line pressing southward to the north of South China. The high temperature heat wave events in summer become more and more normal. From June 1 to August 18, 2022, the average number of high temperature days in China is 12.5 days, 5.3 days more than that in the same period of the normal year, which is the highest in the same period of history since 1961; The number of high temperature days in 2023 is only next to that in 2022, 3.9 days more than that in the same period of the year. The research shows that the historical hot summer or hot year will be a new normal for half of the world's population in the next 20 years, and many regions will probably turn into a new seasonal hot climate in the next 40 years.

The global observation system shows that the frequency and intensity of extreme weather and climate events and the severity of their impacts have not only changed since the 1950s, but will continue to change and strengthen with the increase of global warming in the future. If global warming can be stabilized at 1.5 ℃, it will obviously limit the change of extreme weather and climate events in the future.

Ding Yihui stressed that under the global warming, extreme weather and climate events have significantly affected the security of many fields in China. This is a new situation and problem that deserves our attention, and it also provides us with important enlightenment for coping with and adapting to climate change:

First, the world has entered a new normal of climate change. It is absolutely necessary to propose and establish new adaptation strategies and coping mechanisms under this new climate normal.

Second, under the general pattern of coordinated development of the national economy, we should pay attention to areas that are more sensitive and vulnerable to extreme weather and climate, such as water conservancy, agriculture and rural areas, ecological environment, and the formulation and implementation of reasonable development and adaptation measures for major coastal cities.

The third is to establish a climate risk assessment and long-term extreme weather and climate early warning system under the new normal climate to deal with serious and even catastrophic disasters caused by major climate risks that may occur in the medium and long term. (Author: Miao Yanli)