近日，北京大学S. Peng团队研究了甲烷在本世纪20年代初在大气中激增的原因。2026年2月5日出版的《科学》杂志发表了这项成果。

大气甲烷（CH₄）增长率在2019年后急剧上升，于2020年达到峰值（16.2?ppb/年），随后在2023年降至8.6?ppb/年。

通过采用多组基于观测与模型预设的羟基自由基（OH）场及甲烷大气数据进行约束的大气反演分析，研究组发现：2020–2021年间OH自由基的下降，以及随后在2022–2023年间的恢复，解释了甲烷增长率年际变化的83%；其余部分则与湿地及内陆水域的排放变化有关，该类排放在2019年至2020–2022年间增加（+8.6?±?2.6?TgCH₄/年），随后在2022年至2023年间减少（−9.9?±?3.3?TgCH₄/年）。2019年至2023年期间的大部分排放变化发生在非洲和亚洲的北热带湿地，而南美洲湿地排放自2019年后有所下降，北极地区排放则呈现增加趋势。

附：英文原文

Title: Why methane surged in the atmosphere during the early 2020s

Author: P. Ciais, Y. Zhu, Y. Cai, X. Lan, S. E. Michel, B. Zheng, Y. Zhao, D. A. Hauglustaine, X. Lin, Y. Zhang, S. Sun, X. Tian, M. Zhao, Y. Wang, J. Chang, X. Dou, Z. Liu, R. Andrew, C. A. Quinn, B. Poulter, Z. Ouyang, W. Yuan, K. Yuan, Q. Zhu, F. Li, N. Pan, H. Tian, X. Yu, G. Rocher-Ros, M. S. Johnson, M. Li, M. Li, D. Feng, P. Raymond, X. Yang, J. G. Canadell, R. B. Jackson, X. Yu, Y. Li, M. Saunois, P. Bousquet, S. Peng

Issue&Volume: 2026-02-05

Abstract: The atmospheric methane (CH4) growth rate surged after 2019, peaking at 16.2 parts per billion per year (ppb year1) in 2020 before declining to 8.6 ppb year1 in 2023. Using multiple atmospheric inversions constrained by observation- and model-based prescribed hydroxyl radical (OH) fields and CH4 atmospheric data, we show that a drop of OH radicals in 2020–2021, followed by recovery in 2022–2023, accounted for 83% of year-on-year variations in the CH4 growth rate, the rest being explained by wetland and inland water emissions, which increased between 2019 and 2020–2022 [+8.6 ± 2.6 teragrams of CH4 per year (TgCH4 year1)] and then decreased between 2022 and 2023 (9.9 ± 3.3 TgCH4 year1). Most emission changes from 2019 to 2023 occurred in northern tropical wetlands in Africa and Asia, whereas South American wetlands emissions declined and Arctic emissions increased after 2019.

DOI: adx8262

Source: https://www.science.org/doi/10.1126/science.adx8262