A43A-0257
Retrieval of Aerosol Within Cloud Fields Using the MODIS Airborne Simulator (MAS)
Thursday, 17 December 2015
Poster Hall (Moscone South)
Leigh A Munchak1,2, Robert C Levy1, Shana Mattoo2, Falguni Patadia3,4, Eric M Wilcox5 and Alexander Marshak1, (1)NASA Goddard Space Flight Center, Greenbelt, MD, United States, (2)Science Systems and Applications, Inc., Lanham, MD, United States, (3)NASA/Goddard Space Flight Ctr, Greenbelt, MD, United States, (4)Morgan State University, Greenbelt, MD, United States, (5)Desert Research Institute Reno, Reno, NV, United States
Abstract:
Passive satellite remote sensing has become essential for obtaining global information about aerosol properties, including aerosol optical depth (AOD) and aerosol fine mode fraction (FMF). However, due to the spatial resolution of satellite aerosol products (typically 3 km and larger), observing aerosol within dense partly cloudy fields is difficult from space. Here, we apply an adapted version of the MODIS Collection 6 dark target algorithm to the 50-meter MODIS airborne simulator retrieved reflectances measured during the SEAC4RS campaign during 2013 to robustly retrieve aerosol with a 500 m resolution. We show good agreement with AERONET and MODIS away from cloud, suggesting that the algorithm is working as expected. However, closer to cloud, significant AOD increases are observed. We investigate the cause of these AOD increases, including examining the potential for undetected cloud contamination, reflectance increases due to unconsidered 3D radiative effects, and the impact of humidification on aerosol properties. In combination with other sensors that flew in SEAC4RS, these high-resolution observations of aerosol in partly cloudy fields can be used to characterize the radiative impact of the “twilight zone” between cloud and aerosol which is typically not considered in current estimates of direct aerosol radiative forcing.
