Chinese researchers say the impact of extreme fires on surface warming can last for decades

The night sky illuminated by extreme fires in high-latitude forests (file photo). Published by Xinhua Agency

The international academic journal "Nature" published online on the 25th the research results of a team led by Yue Chao, a young scientist at Northwest A & F University, titled "Surface Warming After Extreme Forest Fires." The article believes that in northern temperate and cold forests, extreme fires will not only increase the temperature of summer surface temperatures, but also amplify the temperature of summer surface temperatures for decades. However, this effect will decrease with the increase of broad-leaved trees. In order to mitigate the climate risk caused by fires, the proportion of broad-leaved trees can be appropriately increased.

Yue Chao (third from left), a young scientist at Northwest A & F University, discussed the scientific research plan with his team (data photo). Published by Xinhua Agency

Climate warming caused by anthropogenic greenhouse gas emissions has led to a widespread increase in extreme fire weather, making individual forest wildfires last longer and burn a larger area. Yue Chao's team found that the area of single forest fire events in forest wildfires in Canada, the United States and Australia has doubled or even tripled in recent decades. These phenomena mean that climate warming has caused extreme fires to become more frequent. However, the impact of frequent extreme fire incidents on the surface climate and their significance to land management policies have attracted little attention from all walks of life.

Research results show that in northern temperate and boreal forests, extreme fires have higher burning intensity per unit area of fire, the burning process releases more carbon dioxide, the tree mortality rate after fire is higher, and the summer surface temperature after fire rises more. In fact, the amplifying effect of extreme fires on summer surface warming can last for decades. But the study also found that this summer surface warming and its amplification effect with the scale of fires decrease as the proportion of broad-leaved trees increases.

This is the forest after the fire (file photo). Published by Xinhua Agency

"For the first time, this study reveals the amplifying effect of extreme fires on ecosystem destruction, forest fire carbon emissions and surface climate feedback from the unique perspective of forest fire scale, and also warns of the possible frequent occurrence of extreme fires-climate warming-A vicious cycle of more extreme fires warns." Yue Chao said that predictions show that future climate warming will lead to more extreme fires in sparsely populated temperate and boreal forests. This article is of significance for scientific understanding of the ecological and climate impacts of extreme fires and how to prevent and control the climate risks of extreme fires.