Which Remotely Sensed Quantities Relate to Pollutants and Toxics at the Surface? An Overview from California, October 2018 and WE-CAN 2018
Abstract
There is perennial interest in better ways of estimating the geographic distribution ("maps") of surface, nose-level pollutants based on remotely sensed column quantities. For areas influenced by fire plumes, the question has especial significance for health effects, both acute hospital morbidity). and chronic (cumulative lifetime dose). Since November 2017, we have detailed TropOMI column retrievals of NO2, CO, HCHO, and some aerosol indices. Retrievals of aerosols by multi-angle methods such as MAIAC (Lyapustin et al., AMT 2018)are available on an expanding set of satellites, low-Earth orbit, and soon, geostationary orbit. We will compare retrieved column quantities to the best available surface composition measurements from state and national monitors, including other species that have similar sources and dispersion.
The 2018 Camp Fire and associated fires affecting the San Francisco Bay Area and the northern Central Valley provide our major comparisons. Observations from the Colorado State / NSF WE-CAN also sampled extraordinarily intense Western Fires. WE-CAN vertical profiles will help describe patterns of column-to-near-surface relationships. We provide an overview of correlations between these remotely retrieved quantities (typically column abundances) and surface measurements for major fires in the American West. Surface measurement stations have varied capabilities, and this sets the limits of our studies for 2018. Ancillary information like estimated plume top near the source, some size information, and Aerosol Index measures of the absorbing component of particles may be useful for more detailed analysis. In some cases, instances and observations show good correlations; others do not. We attempt some general guidance on discriminating these cases. As time allows, we evaluate the success of "local calibration" of the column-to-surface relationships, exploiting multiple measurements with similar chemical and physical conditions. Conceptually, if we can form an appropriate x-y scatterplot of column and surface quantities, the method uses not simple y-to-x proportionality but rather an implied slope. Chatfield et al. (ACP D, 2019, submitted) found that using these methods to relate AOT and PM2.5 can partially resolve uncertainties regarding ambient backgrounds and dilution.- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2019
- Bibcode:
- 2019AGUFM.A51F..07C
- Keywords:
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- 0305 Aerosols and particles;
- ATMOSPHERIC COMPOSITION AND STRUCTURE;
- 3360 Remote sensing;
- ATMOSPHERIC PROCESSES;
- 4301 Atmospheric;
- NATURAL HAZARDS;
- 4337 Remote sensing and disasters;
- NATURAL HAZARDS