The influence of snow cover on Ozone Monitor Instrument formaldehyde observations

Howlett，Careyanne1; Abad，Gonzalo González2; Miller，Christopher Chan2,3; Nowlan，Caroline Rebecca2; Ayazpour，Zolal4; Zhu，Lei5

2023

10.20937/ATM.53134

Atmosfera   影响因子和分区

0187-6236

2395-8812

Formaldehyde (HCHO) is measured from space using backscattered ultraviolet sun-light. Because of HCHO’s short lifetime, space-based observations of HCHO can serve as a proxy for volatile organic compounds, helping to characterize their global emissions and distributions. HCHO satellite observations rely on air mass factor (AMF) calculations to transform fitted slant columns into vertical column densities (VCD’s). Most HCHO satellite products do not explicitly consider the presence of snow on the ground during the calculation of AMFs. In this study, we leverage information from the Moderate-Resolution Imaging Spectroradiometer (MODIS) bidirectional reflectance distribution function (BRDF), MODIS snow cover information, and the Interactive Multisensor Snow and Ice Mapping System to evaluate the impact of ground snow on Ozone Monitoring Instrument (OMI) HCHO retrievals. We focus our analysis on the year 2005. We compare AMFs computed using daily MODIS BRDF to AMFs computed using OMI’s surface reflectance climatology, the baseline for NASA’s OMHCHO product. Over snow-covered regions, both sets of AMFs show significant differences. We observe two different behaviors. Regions with permanent snow cover (Greenland and Antarctica) show smaller AMFs calculated with MODIS BRDF than with the OMI climatology resulting in a 6% median annual increase of HCHO VCDs. Over regions with seasonal snow cover, the situation is more complex with more variability in the differences during the year. For example, a February 2005 case study over Europe shows that the NASA OMHCHO VCDs (calculated using the OMI Lambertian climatology) are on average 16% larger than HCHO columns retrieved using daily MODIS BRDF information

air mass factor BRDF formaldehyde ice MODIS OMI snow

SCI

英语

其他

National Aeronautics and Space Administration[80NSSC18K0691];

Meteorology & Atmospheric Sciences

Meteorology & Atmospheric Sciences

WOS:000982100400010

CENTRO CIENCIAS ATMOSFERA UNAM

2-s2.0-85153740065

Scopus

1.Khoury College of Computer Science,Northeastern University,Boston,02155,United States
2.Harvard-Smithsonian Center for Astrophysics,Cambridge,02138,United States
3.John A. Paulson School of Engineering and Applied Sciences,Harvard University,Cambridge,02138,United States
4.Department of Civil,Structural and Environmental Engineering,University at Buffalo,Buffalo,14228,United States
5.School of Environmental Science and Engineering,Southern University of Science and Technology,Shenzhen,Guangdong,518055,China

Howlett，Careyanne,Abad，Gonzalo González,Miller，Christopher Chan,et al. The influence of snow cover on Ozone Monitor Instrument formaldehyde observations[J]. Atmosfera,2023,37(1):159-174.

Howlett，Careyanne,Abad，Gonzalo González,Miller，Christopher Chan,Nowlan，Caroline Rebecca,Ayazpour，Zolal,&Zhu，Lei.(2023).The influence of snow cover on Ozone Monitor Instrument formaldehyde observations.Atmosfera,37(1),159-174.

Howlett，Careyanne,et al."The influence of snow cover on Ozone Monitor Instrument formaldehyde observations".Atmosfera 37.1(2023):159-174.