Pedestrians holding umbrellas to shield from the sun and heat walk in the street in Beijing, June 23, 2023. (Photo: China News Service/Jia Tianyong)

In what is believed to be the hottest week on Earth in at least 100,000 years, China issued a blue book on climate change on Saturday, warning of ever more frequent extreme heat events across the country and rising climate risks. 

Located in a sensitive region when it comes to global warming, China has been significantly affected by it, with a series of indicators reaching new highs, including average summer temperature, coastal sea levels, and active layer thickness in permafrost regions, according to the blue book.

According to meteorological records, 2015-22 has become the warmest eight years on record in China, the China Meteorological Administration confirmed. Over the past decade (2013-22), the global average temperature was 1.14 C higher than pre-industrial levels.

China's warming rate is higher than the global average, and the frequency of extreme heat events is significantly increasing, the Blue Book on Climate Change in China (2023) noted. A total of 3,501 extreme heat events were recorded in 2022, the most frequent since 1961. Among them, 366 events in Southwest China's Chongqing Municipality, Central China's Hubei Province, and other regions saw temperatures surpassing historical records.

Average annual precipitation levels in China are also rising, along with instances of extreme rainfall. From 1961 to 2022, the average annual precipitation in China increased by 0.8 percent every 10 years, with great regional differences in precipitation changes.

The number of days with accumulated heavy rainfall (daily precipitation ≥ 50 millimeters) in China is also on the rise, increasing by an average of 4.2 percent every 10 years.

As a result, China's climate risk index is climbing. 2022 saw both heat and drought risk indices reaching their highest levels since 1961. 

On Sunday, China's National Meteorological Center issued an orange alert for high temperatures nationwide for the sixth straight day, forecasting 35 C and higher temperature across the majority of the country, with six regions reaching up to 40 C and above. 

CNN also reported on the hottest week globally, as the average global temperature on Monday reached a record-high 17.01 C and climbed even further to 17.18 C the next day, the US National Centers for Environmental Prediction's data showed. Europe's climate change authority also confirmed record highs from their weather station services.

This week's records are probably the warmest in "at least 100,000 years," Jennifer Francis, a senior scientist at Woodwell Climate Research Center, was quoted as saying in the CNN report.

The scorching weather is a result of the onset of El Nino conditions coupled with global warming, said analysts. The World Meteorological Organization declared on Tuesday that El Nino conditions have developed in the tropical Pacific for the first time in seven years, setting the stage for a likely surge in global temperatures and disruptive weather and climate patterns.

"Last year's and this year's high temperatures are highly abnormal," said Sun Ying, chief scientist at China's National Climate Center, at the Eco Forum Global Guiyang 2023.

 "The impact of these extreme temperatures goes beyond mere heat. Last year's high temperatures triggered numerous events including the severe drought in the Yangtze River basin, which was exacerbated by the lack of rainfall following the heat wave."

To cope with these challenges, China has emergency plans in place to deal with the ever-changing weather conditions, Sun noted. 

She introduced that the current focus is on the "three accuracies," namely accurate forecasting, accurate predictions, and accurate services. The goal is to provide precise forecasts for disastrous weather events as early as possible, in order to strengthen public awareness and preparedness.

According to Sun, human activities are the most significant cause of global warming. The impact of human activities on the climate system, including land degradation, rising sea levels, ecosystem degradation, and glacier retreat, have already had severe consequences on society. These effects may have serious implications for the future of human survival and development. 

"It is essential for us to unite with the international community to confront climate change. On the one hand, we need to strengthen our scientific understanding and continue conducting in-depth research on climate change. Besides this, we must actively adapt to climate change by enhancing our capacity to cope with climate risks and disasters. Most importantly, we need to reduce greenhouse gas emissions through various means to mitigate climate warming. We can start by taking action on an individual level and collaborating with society as a whole to alleviate the impact of climate change," she said.

According to the blue book, global ocean warming has also significantly accelerated, with ocean heat content reaching new highs. The global mean sea level continues to rise, and China's coastal sea level shows an overall accelerating upward trend.

As for the cryosphere, global glacier retreat has sped up. From 1960 to 2022, glaciers worldwide have been in a state of melting and retreat, with an accelerated pace observed since 1985. Multiple glaciers in China are experiencing an accelerated melting trend. 

Vegetation coverage in China has been steadily on the rise, showing a continuous greening trend, the blue book suggested. From 2000 to 2022, the annual average Normalized Difference Vegetation Index (NDVI) in China has exhibited an upward trend. In 2022, the average NDVI in China was 0.379, marking an increase of 8.7 percent compared with that from 2011 to 2020.