Below is a one-year simulation of surface-level PM2.5 concentrations simulated in a new
nested South America domain (in prep) for the chemical transport model GEOS-Chem classic.
Accompanying this forward model simulation is an adjoint calculation of
sensitivities of PM2.5 in the
city of Santiago, Chile to emissions of its chemical precursors. In the below figure we calculate
sensitivities to ammonia.