Comparing multiple model-derived aerosol optical properties to collocated ground-based and satellite measurements
Ilissa B. Ocko1 and Paul A. Ginoux21Environmental Defense Fund, New York, 10010, USA 2NOAA Geophysical Fluid Dynamics Laboratory, Princeton, 08540, USA
Received: 31 Aug 2016 – Accepted for review: 12 Oct 2016 – Discussion started: 17 Oct 2016
Abstract. Anthropogenic aerosols are a key factor governing Earth’s climate, and play a central role in human-caused climate change. However, because of aerosols’ complex physical, optical, and dynamical properties, aerosols are one of the most uncertain aspects of climate modeling. Fortunately, aerosol measurement networks over the past few decades have led to the establishment of long-term observations for numerous locations worldwide. Further, the availability of datasets from several different measurement techniques (such as ground-based and satellite instruments) can help scientists increasingly improve modeling efforts. This study explores the value of evaluating several model-simulated aerosol properties with data from collocated instruments. We compare optical depth (total, scattering, and absorption), single scattering albedo, Ångström exponent, and extinction vertical profiles in two prominent global climate models to seasonal observations from collocated instruments (AERONET and CALIOP) at seven polluted and biomass burning regions worldwide. We find that models may accurately reproduce one variable while totally failing at another; data from collocated instruments can reveal underlying aerosol-governing physics; column properties may wash out important vertical distinctions; and "improved" models does not mean all aspects are improved. We conclude that it is important to make use of all available data (parameters and instruments) when evaluating aerosol properties derived by models.
Ocko, I. B. and Ginoux, P. A.: Comparing multiple model-derived aerosol optical properties to collocated ground-based and satellite measurements, Atmos. Chem. Phys. Discuss., doi:10.5194/acp-2016-790, in review, 2016.