State Key Laboratory of Loess and Quaternary Geology, Center for Excellence in Quaternary Science and Global Change, Chinese Academy of Sciences, Xi'an 710061, China.
Key Laboratory of Aerosol Chemistry and Physics, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an 710061, China.
Proc Natl Acad Sci U S A. 2020 Mar 10;117(10):5184-5189. doi: 10.1073/pnas.1822035117. Epub 2020 Feb 24.
Wildfire can influence climate directly and indirectly, but little is known about the relationships between wildfire and climate during the Quaternary, especially how wildfire patterns varied over glacial-interglacial cycles. Here, we present a high-resolution soot record from the Chinese Loess Plateau; this is a record of large-scale, high-intensity fires over the past 2.6 My. We observed a unique and distinct glacial-interglacial cyclicity of soot over the entire Quaternary Period synchronous with marine δO and dust records, which suggests that ice-volume-modulated aridity controlled wildfire occurrences, soot production, and dust fluxes in central Asia. The high-intensity fires were also found to be anticorrelated with global atmospheric CO records over the past eight glacial-interglacial cycles, implying a possible connection between the fires, dust, and climate mediated through the iron cycle. The significance of this hypothetical connection remains to be determined, but the relationships revealed in this study hint at the potential importance of wildfire for the global climate system.
野火可以直接或间接影响气候，但人们对第四纪野火与气候之间的关系知之甚少，尤其是在冰期-间冰期循环中野火模式是如何变化的。在这里，我们呈现了来自中国黄土高原的高分辨率烟尘记录；这是过去 260 万年大规模高强度火灾的记录。我们观察到整个第四纪时期烟尘存在独特而明显的冰期-间冰期周期性，与海洋δO 和尘埃记录同步，这表明冰量调节的干旱控制了中亚野火的发生、烟尘的产生和尘埃通量。过去八个冰期-间冰期循环中，高强度火灾也与全球大气 CO 记录呈反相关，这意味着火灾、尘埃和气候之间可能通过铁循环联系在一起。这种假设联系的意义仍有待确定，但本研究揭示的关系表明，野火对全球气候系统可能具有重要意义。
