In response to a strong El Niño, fires in Indonesia during September and October 2015 released a large amount of carbon dioxide and created a massive regional smoke cloud that severely degraded air quality in many urban centers across Southeast Asia. Although several lines of evidence indicate that peat burning was a dominant contributor to emissions in the region, El Niño-induced drought is also known to increase deforestation fires and agricultural waste burning in plantations. As a result, uncertainties remain with respect to partitioning emissions among different ecosystem and fire types. Here we measured the radiocarbon content (¹⁴C) of carbonaceous aerosol samples collected in Singapore from September 2014 through October 2015, with the aim of identifying the age and origin of fire-emitted fine particulate matter (particulate matter with an aerodynamic diameter less than or equal to 2.5 μm). The Δ¹⁴C of fire-emitted aerosol was −76 ± 51‰, corresponding to a carbon pool of combusted organic matter with a mean turnover time of 800 ± 420 y. Our observations indicated that smoke plumes reaching Singapore originated primarily from peat burning (∼85%), and not from deforestation fires or waste burning. Atmospheric transport modeling confirmed that fires in Sumatra and Borneo were dominant contributors to elevated PM_2.5 in Singapore during the fire season. The mean age of the carbonaceous aerosol, which predates the Industrial Revolution, highlights the importance of improving peatland fire management during future El Niño events for meeting climate mitigation and air quality commitments.

为应对厄尔尼诺现象，2015年9月至10月印度尼西亚发生的大火释放出大量二氧化碳，并形成了巨大的区域烟云，严重恶化了东南亚许多城市中心的空气质量。虽然一些证据表明，泥炭燃烧是主要贡献者在该地区的排放量，萨尔瓦多NIN Ø诱导的干旱也被称为增加砍伐森林火灾和农业废物焚烧种植。结果，在不同生态系统和火灾类型之间分配排放方面仍然存在不确定性。在这里，我们测量了放射性碳含量（¹⁴C）从2014年9月至2015年10月在新加坡收集的碳质气溶胶样品，目的是确定发射火的细颗粒物（空气动力学直径小于或等于2.5微米的颗粒物）的年龄和来源。的Δ ¹⁴火发射气溶胶的C为-76±51‰，对应于燃烧的有机物的碳池800±420为y的平均周转时间。我们的观察表明，进入新加坡的烟羽主要来自泥炭燃烧（约占85％），而不是森林砍伐大火或废物燃烧所致。大气传输模型证实，苏门答腊和婆罗洲的火灾是造成PM _2.5升高的主要因素在大火季节在新加坡。在工业革命之前，碳质气溶胶的平均年龄凸显了在未来的厄尔尼诺事件中改善泥炭地火管理的重要性，以满足气候减缓和空气质量承诺。