New Global Deep Blue Aerosol Product over Land and Ocean from VIIRS, and Its comparisons with MODIS

The impacts of natural and anthropogenic sources of air pollution on climate and human health have continued to gain attention from the scientific community. In order to facilitate these effects, high quality consistent long-term global aerosol data records from satellites are essential. Several EOS-era instruments (e.g., SeaWiFS, MODIS, and MISR) are able to provide such information with a high degree of fidelity. However, with the aging MODIS sensors and the launch of the VIIRS instrument on Suomi NPP in late 2011, the continuation of long-term aerosol data records suitable for climate studies from MODIS to VIIRS is needed urgently. VIIRS was designed to have similar capabilities to MODIS, with similar visible/infrared spectral channels, and spatial/ temporal resolution. However, small but significant differences in several key channels used in aerosol retrievals between MODIS and VIIRS mean that significant effort is required to revise aerosol models and surface reflectance determination modules previously developed using MODIS data. In this study, we will show the global (land and ocean) distribution of aerosols from Version 1 of the VIIRS Deep Blue data set. The preliminary validation results of these new VIIRS Deep Blue aerosol products using data from AERONET sunphotometers over land and ocean will be discussed. We will also compare the monthly averaged Deep Blue aerosol optical thickness (AOT) from VIIRS with the MODIS C6 products to investigate if any systematic biases may exist between MODIS C6 and VIIRS AOT.