Abstract:
Except in the context of major pollution events, the impact of airborne particles on planetary habitability was largely unappreciated until the dawn of the satellite age. Space-based imagery starting in the late 1960s provided evidence that aerosols can be transported thousands of kilometers, frequently in sufficient amounts to affect global climate as well as regional air quality. The MODIS and MISR instruments, both aboard the NASA Earth Observing System’s Terra satellite, were launched into orbit in December 1999, marking the beginning of the EOS era. MODIS is a broad-swath, single-angle imager with 36 spectral channels, observing the entire planet every day or two, whereas MISR, an entirely new instrument concept at the time, has nine separate cameras pointing toward Earth at different angles, each acquiring data in four spectral bands, and sampling the whole planet about once per week. Both instruments continue to acquire data nominally after more than 22 years.
After almost two decades of studying the MISR data, developing and refining the analysis tools, we are now learning more about Earth than we are about MISR. From the hyper-stereo observations we derive geometrically the heights and associated motion vectors for wildfire, volcano, and dust plumes. From reflectance measured at multiple slant paths through the atmosphere, aerosol amount can be retrieved with substantial confidence, even over relatively bright land surfaces. Taken together, the multi-angle, multi-spectral data also contain qualitative information about particle size, shape, and light-absorption properties, provided the column-amount is sufficiently high. This talk will review what we are learning about how wildfire smoke particles evolve downwind, what volcanos, even in remote areas, emit over time, the way desert dust is mobilized and transported across oceans, and how these results can be used to constrain and to refine climate and air quality models.
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/