There is a great need to define health-affecting pollution by small particles as “respirable aerosol”. The wintertime San Joaquin Valley experiences severe episodes that need full maps. A few air pollution monitors are set out by agencies in such regions. Satellite data on haziness and daily calibration using the monitors map out improved pollution estimates for the winter of 2012–2013. These show patterns of valuable empirical information about sources, transport, and cleanout of pollution.