Summary

Description

The Global Annual PM2.5 Grids from MODIS, MISR and SeaWiFS Aerosol Optical Depth (AOD) data sets represent a series of three-year running mean grids (1998-2012) of fine particulate matter (solid particles and liquid droplets) that were derived from a combination of MODIS (Moderate Resolution Imaging Spectroradiometer), MISR (Multi-angle Imaging SpectroRadiometer) and SeaWIFS (Sea-Viewing Wide Field-of-View Sensor) AOD satellite retrievals. Together the grids provide a continuous surface of concentrations in micrograms per cubic meter of particulate matter 2.5 micrometers or smaller (PM2.5) for health and environmental research. For each satellite-derived PM2.5 source, the total column retrievals of AOD were converted to near-ground PM2.5 levels using the GEOS-Chem chemical transport model to represent local relationships between AOD and PM2.5. A global decadal (2001-2010) mean PM2.5 concentration grid was also produced. The raster grids have a grid cell resolution of 6 arc-minutes (0.1 degree or approximately 10 km at the equator) and cover the global land surface from 70 degrees north to 55 degrees south. Compared to SEDAC’s earlier data set, Global Annual Average PM2.5 Grids from MODIS and MISR Aerosol Optical Depth (AOD), v1 (2001-2010), this data set provides higher accuracy; longer temporal range; higher resolution (0.1 x 0.1 degrees); and time varying AOD to PM2.5 relationships, necessary for appropriate representation of trends.