On July 8, on the occasion of Eco Forum Global Guiyang 2023, China Meteorological Administration (CMA) unveiled Blue Book on Climate Change of China 2023 (hereafter referred to as the Blue Book), which captures a comprehensive picture of the latest monitoring information of climate change in China and the world from the perspectives of atmosphere, hydrosphere, cryosphere, biosphere and drivers of climate change.

The Blue Book pointed out the global warming trend was still persisting. The global mean temperature dataset of CMA showcased that the global average temperature in 2022 recorded 1.13 ° C above the pre-industrial levels, ranking the sixth highest since meteorological observations existed in 1850. The years from 2015 to 2022 were the eight warmest years on record. The average surface temperature in China in 2022 registered 0.92 ° C higher than that in normal years, which was one of the three warmest years since the early 20th century. From 1961 to 2022, the average annual precipitation in China showed a rising trend, characterized by obvious regional differences in terms of precipitation variation. The average annual precipitation in Qinghai-Tibet showed a significant rising trend, while the average annual precipitation in Southwest China showed a dropping trend.

Global mean temperature anomaly from 1850 to 2022 (relative to the average from 1850 to 1900)

Annual days of cumulative rainstorm registered by meteorological stations in China from 1961 to 2022

In China, the frequency of extreme heat wave events is on the rise. The number of extreme heavy precipitation events is mounting, and the climate risk index takes on an increasing trend. From 1961 to 2022, the frequency of extreme heat wave events in China showed a significant increase trend, and that of extreme heat wave events in 2022 has ranked the first since 1961. The frequency of extreme daily precipitation events in China showed an increasing trend. The average intensity of typhoons landing in China has fluctuated and intensified since the late 1990s. China's climate risk index shows an increasing trend, and the heat wave and drought risk index in 2022 topped the list since 1961.

Global Distribution of SST Anomaly in 2022

Global ocean warming has accelerated markedly, and the average sea level has continued to rise. From 1958 to 2022, the global ocean heat content showed a significant increase trend, and in 2022, the global mean sea level reached the highest level since satellite observations began. From 1980 to 2022, the sea level change in China's coastal areas displayed an accelerating trend, and in 2022, the sea level in China's coastal areas reached the highest level since 1980. The annual variation of China's surface water resources is noticeable, and the water level of Qinghai Lake has risen for 18 consecutive years.

Global glacier melting was accelerating, and was in a constant state of retreat. The Arctic sea ice extent was dwindling, and showcased a consistent decreasing trend compared with that from 1979 to 2022. The Antarctic sea ice extent reached a new low, and in February 2022, that was 27.9% smaller than usual, reaching the minimum since satellite observation records began.

Vegetation cover in China has been steadily expanding and showing a continuous greening trend. From 2000 to 2022, the average annual normalized vegetation index (NDVI) in China showed a significant upward trend.

Change of climate risk index in China from 1961 to 2022

The Blue Book demonstrated that the global concentration of major greenhouse gases increased year by year, and the global atmospheric average concentration of carbon dioxide, methane and nitrous oxide has reached the highest level since the observation records in 2021. In China, the aerosol optical thickness generally showed a decreasing trend, and the characteristics of staged change are prominent.

Since 2011, CMA has consecutively released this annual document for 13 issues.

Editor: Liu Shuqiao