Towards Measuring Atmospheric CO2 Enhancements and Quantifying CO2 Emissions from Wildfires – an Airborne Demonstration
Jianping Mao, NASA GSFC/University of Maryland, jianping.mao@nasa.gov (Presenter)
James B. Abshire, NASA GSFC and Univ. of Maryland, james.b.abshire@nasa.gov
Stephan Randolph Kawa, NASA GSFC, stephan.r.kawa@nasa.gov
Haris Riris, NASA GSFC, haris.riris@nasa.gov
Xiaoli Sun, NASA GSFC, xiaoli.sun-1@nasa.gov
Paul T. Kolbeck, University of Maryland, kolbeckpaul@gmail.com
Brad Weir, NASA GSFC GMAO / GESTAR USRA, brad.weir@nasa.gov
Niels Andela, NASA GSFC, niels.andela@nasa.gov
Vegetation fires are a major source of greenhouse gases. Recent wildfires in California have had profound impacts on air quality and have emitted a record amount of CO2. The CO2 emissions from fires estimated with fire emission models or databases have large discrepancies and uncertainties. Ground-based and airborne measurements of fire emissions are few and difficulty to obtain, and CO2 retrievals from satellite measurements using passive remote sensing are significantly degraded by scattering effects of smoke in the scene.
NASA Goddard Space Flight Center has developed the CO2 Sounder lidar, an integrated-path, differential absorption lidar approach to measure global atmospheric column-averaged CO2 (XCO2) from space as a candidate for NASA’s Planned ASCENDS mission. This pulsed laser approach measures CO2 absorption at multiple wavelengths across a CO2 line centered at 1572.335 nm. Measurements of height-resolved laser backscatter profiles allow this technique to accurately estimate XCO2 through fire smoke plumes.
We demonstrate this measurement capability over wildfires using lidar measurements from the summer 2017 ASCENDS/ABoVE airborne science campaign. On July 21, the calibration flight was conducted in the Central Valley, CA. Significant CO2 enhancements in lidar XCO2 retrievals were detected over smoke plumes blown from the Detwiler wildfires near the Yosemite National Park. During the August 8 flight over Vancouver Island, there were dense smoke plumes from the record-breaking wildfires in the Canadian Rockies. The aircraft overflow this region at a 9-km altitude, the lidar XCO2 retrievals showed up to a few ppm enhancements. We compared these enhancements with those from the Goddard chemistry transport models using the Global Fire Emission Database (GFED) and the Quick Fire Emissions Dataset (QFED). The comparison results suggest that the CO2 emissions from GFED and QFED for these wildfires were underestimated by more than a factor of 2.
The results show that future airborne campaigns and spaceborne missions with this capability will significantly reduce the uncertainty in emission modeling and improve estimates of the impact of wildfires on air quality and ecosystem. This capability will further benefit atmospheric transport process studies and estimates of carbon fluxes.
Poster: Poster_Mao__140_25.pdf
Presentation Type: Poster
Session: 3.2a Observations to quantify hot spots and local/urban emissions
Session Date: Wednesday (6/16) 9:45 AM