On the Role of the Flaming to Smoldering Transition in the Seasonal Cycle of African Fire Emissions
On the Role of the Flaming to Smoldering Transition in the Seasonal Cycle of African Fire Emissions
复制标题
燃烧到阴燃过渡在非洲火灾排放季节性循环中的作用
DOI：
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发表时间：
2018
影响因子：
5.2
通讯作者：
Yilong Wang
中科院分区：
文献类型：
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作者：
B. Zheng;F. Chevallier;P. Ciais;Yi Yin;Yilong Wang
燃烧面积的卫星估计，相关的一氧化碳（CO）排放量的估计，和CO柱检索不同意在非洲的火灾高峰月，明显的北方和南部非洲，虽然不同的燃烧季节性。在这里，我们使用（1）2005-2016年期间对流层CO柱中污染测量的自上而下的贝叶斯反演来分析这个长期存在的问题，以及（2）自下而上的全球火灾排放数据库4.1 s。我们发现，全球火灾排放数据库4.1 s在火灾季节后期低估了12-62%的CO排放量，并假设这部分是因为它假设了季节性静态排放因子。然而，排放因子必须在整个季节中变化以使自上而下和自下而上一致的程度无法通过过去的实地测量来确认。改进对燃烧面积、燃料燃烧和排放因子季节性的观测约束，将进一步减少自下而上和自上而下排放估计之间的差异。
Satellite estimates of burned area, associated carbon monoxide (CO) emission estimates, and CO column retrievals do not agree on the peak fire month in Africa, evident in both Northern and Southern Africa though distinct in the burning seasonality. Here we analyze this long‐standing problem using (1) a top‐down Bayesian inversion of Measurements Of Pollution In The Troposphere CO columns during 2005–2016 into surface CO emissions and (2) the bottom‐up Global Fire Emissions Database 4.1 s. We show that Global Fire Emissions Database 4.1 s underestimates CO emissions by 12–62% in the late fire season and hypothesize that this is partly because it assumes seasonally static emission factors. However, the degree to which emission factors would have to vary through the season to bring top‐down and bottom‐up in agreement cannot be confirmed by past field‐based measurements. Improved observational constraint on the seasonality of burned area, fuel combustion, and emission factors would further reduce the discrepancy between bottom‐up and top‐down emission estimates.