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Title: Validation of satellite formaldehyde (HCHO) retrievals using observations from 12 aircraft campaigns
Abstract. Formaldehyde (HCHO) has been measured from space for morethan 2 decades. Owing to its short atmospheric lifetime, satellite HCHOdata are used widely as a proxy of volatile organic compounds (VOCs; pleaserefer to Appendix A for abbreviations and acronyms), providing constraintson underlying emissions and chemistry. However, satellite HCHO products fromdifferent satellite sensors using different algorithms have received littlevalidation so far. The accuracy and consistency of HCHO retrievals remainlargely unclear. Here we develop a validation platform for satellite HCHOretrievals using in situ observations from 12 aircraft campaigns with a chemicaltransport model (GEOS-Chem) as the intercomparison method. Application tothe NASA operational OMI HCHO product indicates negative biases (−44.5 %to −21.7 %) under high-HCHO conditions, while it indicates high biases (+66.1 % to+112.1 %) under low-HCHO conditions. Under both conditions, HCHO a priorivertical profiles are likely not the main driver of the biases. By providingquick assessment of systematic biases in satellite products over largedomains, the platform facilitates, in an iterative process, optimization ofretrieval settings and the minimization of retrieval biases. It is alsocomplementary to localized validation efforts based on ground observationsand aircraft spirals.  more » « less
Award ID(s):
1929210 1650275
PAR ID:
10203572
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ; ; ; ;
Date Published:
Journal Name:
Atmospheric Chemistry and Physics
Volume:
20
Issue:
20
ISSN:
1680-7324
Page Range / eLocation ID:
12329 to 12345
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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