Abstract:
The Orbiting Carbon Observatory (OCO-2) makes global measurements of CO2. This seminar reviews how the OCO-2 experiment retrieves CO2, and discusses physics (due to 3D cloud radiative effects) which is not included in the operational retrieval. Clouds outside of the OCO-2 footprints can scatter light towards observation footprints, and thereby increase observed radiances. Sun-cloud-observation footprint geometry can also lead to cloud shadowing (a decrease in radiance). Analysis of OCO-2 data files indicates that there are many more “cloud brightening” than “cloud shadowing” events. 3D and 1D radiative transfer calculations, and analysis of several years of OCO-2 and Moderate Resolution Imaging Spectrometer (MODIS) data files, indicate that a) retrievals are impacted when observations are within 4 km of clouds, and b) 40% of OCO-2 retrievals are within 4 km of clouds. 3D cloud effect biases are calculated over ocean and land for the northern and southern hemispheres. Mitigation of the 3D cloud effect biases is discussed in terms of a simple empirical look-up table algorithm.
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Zoom Info: If you’re interested in attending virtually, please contact Heather Mallander (heather.mallander@lasp.colorado.edu) to be added to the mailing list. For more info: https://lasp.colorado.edu/home/events-and-outreach/lasp-science-seminars/
Address Info:
LASP – Space Science Building
SPSC-W120
3665 Discovery Drive, Boulder, CO 80303
Map: https://lasp.colorado.edu/home/maps/spsc-w120/
The Physics Frontiers Centers (PFC) program supports university-based centers and institutes where the collective efforts of a larger group of individuals can enable transformational advances in the most promising research areas. The program is designed to foster major breakthroughs at the intellectual frontiers of physics by providing needed resources such as combinations of talents, skills, disciplines, and/or specialized infrastructure, not usually available to individual investigators or small groups, in an environment in which the collective efforts of the larger group can be shown to be seminal to promoting significant progress in the science and the education of students. PFCs also include creative, substantive activities aimed at enhancing education, broadening participation of traditionally underrepresented groups, and outreach to the scientific community and general public.