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Three methods of analyzing Stratospheric Aerosol and Gas Experiment (SAGE) II tropospheric aerosol extinction data are described and intercompared in terms of global maps and vertical contour plots of the extinction coefficient, or its equivalent. The first method, which has been in use for several years, is found to be biased toward smaller aerosols (effective radius < about 0.25 mum), while the second more recently developed method characterizes the distribution of larger aerosols (effective radius > 0.25 mum). The third method which, unlike the first two methods, is capable of producing an altitude resolved aerosol climatology down to about I km above the earth's surface, requires an assumption about the amount of cloud contamination in the data set. Given the correctness of this assumption, the method is able to derive the total extinction due to both large and small aerosols. Aerosol climatologies produced by all three methods are shown and intercompared, with particular emphasis on the lofting of dust from Asian and other Northern Hemisphere deserts and its subsequent advection over the western Pacific Ocean.