A11T-05
The Chemical Link between Isoprene and Formaldehyde
Monday, 14 December 2015: 09:10
3004 (Moscone West)
Glenn Wolfe1,2, Jennifer Kaiser3, Thomas F Hanisco2, Frank N Keutsch4, Joost A De Gouw5, Jessica Gilman6, Martin Graus7, Courtney Dyan Hatch8, John S Holloway9, Larry Wayne Horowitz10, Ben H. Lee11, Brian M Lerner12, Felipe Lopez-Hilfiker11, Jingqiu Mao13, Margaret Rosemary Marvin14, Jeff Peischl15, Ilana B Pollack16, James M Roberts12, Thomas B Ryerson17, Joel A Thornton18, Patrick R Veres12 and Carsten Warneke12, (1)University of Maryland Baltimore County, Joint Center for Earth Systems Technology, Baltimore, MD, United States, (2)NASA Goddard Space Flight Center, Greenbelt, MD, United States, (3)University of Wisconsin- Madison, Madison, WI, United States, (4)UW Madison, Madison, WI, United States, (5)NOAA Earth System Research Lab, Boulder, CO, United States, (6)NOAA ESRL, Boulder, CO, United States, (7)Cooperative Institute for Research in Environmental Sciences, Boulder, CO, United States, (8)Hendrix College, Conway, AR, United States, (9)CIRES, Boulder, CO, United States, (10)Geophysical Fluid Dynamics Laboratory, Princeton, NJ, United States, (11)University of Washington Seattle Campus, Seattle, WA, United States, (12)NOAA Boulder, Boulder, CO, United States, (13)Princeton University, Princeton, NJ, United States, (14)University of Maryland College Park, College Park, MD, United States, (15)Cooperative Institute for Research in Environmental Sciences, University of Colorado Boulder, Boulder, CO, United States, (16)ESRL Chemical Sciences Division, NOAA, Boulder, CO, United States, (17)NOAA, Boulder, CO, United States, (18)Univ Washington - Seattle, Seattle, WA, United States
Abstract:
Isoprene-fueled photochemistry defines near-surface atmospheric composition in many regions of the world. Formaldehyde (HCHO) is a major product of, and thus a tracer for, this chemistry. As one of the few volatile organic compounds (VOC) observable via remote sensing, HCHO offers an invaluable constraint on the global distribution of isoprene emissions. Shortcomings in current chemical mechanisms, however, challenge our understanding of the link between isoprene emissions and HCHO abundance. Uncertainties are most severe under low-NO
x conditions, which are often prevalent in regions with high biogenic emissions.
Using observations from the 2013 SENEX mission, we will quantify the isoprene-HCHO relationship across the wide range of chemical regimes encountered in the southeast U.S. Model-assisted analysis will focus on the NOx dependence of HCHO production and its mechanistic underpinnings. Accurate model representation of this relationship is crucial for top-down constraints of isoprene emissions. It is also a benchmark for overall mechanism performance with regard to VOC degradation.
