近日，美国加州理工学院Byrne, Brendan研究组报道了2023年加拿大野火的碳排放量。2024年8月28日出版的《自然》杂志发表了这项成果。

据研究人员介绍，与前四十年相比，2023年的加拿大森林大火在规模和强度上都达到了极限，平均年烧毁面积是以往的7倍多。

研究人员基于卫星一氧化碳观测的逆建模，量化了2023年5月至9月这些火灾的碳排放量。研究发现，碳排放量为647TgC (570-727TgC)，与大国的化石燃料年排放量相当。研究人员还发现，广泛的干热天气是火灾蔓延的主要驱动因素，2023年是至少自1980年以来最温暖和最干燥的一年。

尽管与历史记录相比，温度是极端的，但气候预估表明，即使在温和的气候减缓情景下(共享社会经济途径，SSP2-4.5)，这些温度在2050年代也可能是典型温度。这样的条件可能会导致火灾活动增加，并抑制加拿大森林的碳吸收，加剧了人们对这些森林作为碳汇的长期持久性的担忧。

附：英文原文

Title: Carbon emissions from the 2023 Canadian wildfires

Author: Byrne, Brendan, Liu, Junjie, Bowman, Kevin W., Pascolini-Campbell, Madeleine, Chatterjee, Abhishek, Pandey, Sudhanshu, Miyazaki, Kazuyuki, van der Werf, Guido R., Wunch, Debra, Wennberg, Paul O., Roehl, Coleen M., Sinha, Saptarshi

Issue&Volume: 2024-08-28

Abstract: The 2023 Canadian forest fires have been extreme in scale and intensity with more than seven times the average annual area burned compared to the previous four decades. Here, we quantify the carbon emissions from these fires from May to September 2023 on the basis of inverse modelling of satellite carbon monoxide observations. We find that the magnitude of the carbon emissions is 647 TgC (570–727TgC), comparable to the annual fossil fuel emissions of large nations, with only India, China and the USA releasing more carbon per year. We find that widespread hot–dry weather was a principal driver of fire spread, with 2023 being the warmest and driest year since at least 1980. Although temperatures were extreme relative to the historical record, climate projections indicate that these temperatures are likely to be typical during the 2050s, even under a moderate climate mitigation scenario (shared socioeconomic pathway, SSP2–4.5). Such conditions are likely to drive increased fire activity and suppress carbon uptake by Canadian forests, adding to concerns about the long-term durability of these forests as a carbon sink.

DOI: 10.1038/s41586-024-07878-z

Source: https://www.nature.com/articles/s41586-024-07878-z