Source backtracking for dust storm emission inversion using adjoint method: case study of northeast China

doi:10.5194/acp-2020-435

GSTDTAP > 地球科学

DOI	10.5194/acp-2020-435
	Source backtracking for dust storm emission inversion using adjoint method: case study of northeast China
	Jianbing Jin, Arjo Segers, Hong Liao, Arnold Heemink, Richard Kranenburg, and Hai Xiang Lin
	2020-07-22
发表期刊	Atmospheric Chemistry and Physics
出版年	2020
英文摘要	Emission inversion using data assimilation fundamentally relies on having the correct assumptions on the emission background error covariance. A perfect covariance accounts for the uncertainty based on prior knowledge, and is able to explain differences between model simulations and observations. In practice, emission uncertainties are constructed empirically, hence a partially unrepresentative covariance is unavoidable. Concerning its complex parameterization, dust emissions are a typical example where the uncertainty could be induced from many underlying inputs, e.g., information on soil composition and moisture, landcover and erosive wind velocity, and these can hardly be taken into account together. This paper describes how an adjoint model can be used to detect errors in the emission uncertainty assumptions. This adjoint based sensitivity method could serve as a supplement of a data assimilation inverse modeling system to trace back the error sources, in case that large observation-minus-simulation residues remain after assimilation based on empirical background covariance. The method follows on application of a data assimilation emission inversion for an extreme severe dust storm over East Asia (Jin et al., 2019b). The assimilation system successfully resolved observation-minus-simulation errors using satellite AOD observations in most of the dust-affected regions. However, a large underestimation of dust in northeast China remained despite the fact the assimilated measurements indicated severe dust plumes there. An adjoint implementation of our dust simulation model is then used to detect the most likely source region for these unresolved dust loads. The backward modeling points to the Horqin desert as source region, which was indicated as a non-source region by the existing emission scheme. The reference emission and uncertainty are then reconstructed over the Horqin desert by assuming higher surface erodibility. After the emission reconstruction, the emission inversion is performed again and the posterior dust simulations and reality are now in much closer harmony. Based on our results, it is advised that emission sources in dust transport models include Horqin desert as a more active source region.
领域	地球科学
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文献类型	期刊论文
条目标识符	http://119.78.100.173/C666/handle/2XK7JSWQ/286721
专题	地球科学
推荐引用方式 GB/T 7714	Jianbing Jin, Arjo Segers, Hong Liao, Arnold Heemink, Richard Kranenburg, and Hai Xiang Lin. Source backtracking for dust storm emission inversion using adjoint method: case study of northeast China[J]. Atmospheric Chemistry and Physics,2020.
APA	Jianbing Jin, Arjo Segers, Hong Liao, Arnold Heemink, Richard Kranenburg, and Hai Xiang Lin.(2020).Source backtracking for dust storm emission inversion using adjoint method: case study of northeast China.Atmospheric Chemistry and Physics.
MLA	Jianbing Jin, Arjo Segers, Hong Liao, Arnold Heemink, Richard Kranenburg, and Hai Xiang Lin."Source backtracking for dust storm emission inversion using adjoint method: case study of northeast China".Atmospheric Chemistry and Physics (2020).