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We present a new product with explicit aerosol corrections, POMINO-TROPOMI, for tropospheric nitrogen dioxide (NO2) vertical column densities (VCDs) over East Asia, based on the newly launched TROPOspheric Monitoring Instrument with an unprecedented high horizontal resolution. Compared to the official TM5-MP-DOMINO (OFFLINE) product, POMINO-TROPOMI shows stronger concentration gradients near emission source locations and better agrees with MAX-DOAS measurements (R2=0.75 ; NMB=0.8 % versus R2=0.68 , NMB=-41.9 %). Sensitivity tests suggest that implicit aerosol corrections, as in TM5-MP-DOMINO, lead to underestimations of NO2 columns by about 25 % over the polluted northern East China region. Reducing the horizontal resolution of a priori NO2 profiles would underestimate the retrieved NO2 columns over isolated city clusters in western China by 35 % but with overestimates of more than 50 % over many offshore coastal areas. The effect of a priori NO2 profiles is more important under calm conditions. [ABSTRACT FROM AUTHOR]

Using the Community Earth System Model (CESM) version 1.2, this study investigates the changes in secondary inorganic aerosols (SIOAs) over the Northern Hemisphere from 1850 to 2007, regional contributions, and consequences on surface air temperature. Results show that SIOAs changes can be divided into two stages. At the first stage (1850–1980), European and North American SIOAs concentrations increase, with a cooling effect especially over Europe and Eastern Siberia. At the second stage (1980–2007), SIOAs concentrations over Europe and North America are reduced with a warming effect in the mid-high latitudes, whereas SIOAs increase over East Asia and South Asia leading to a cooling effect there. The temperature changes over the emission source regions are mainly driven by radiative forcing. Horizontal transfer of heat leads to a temperature response in the Siberian region. [ABSTRACT FROM AUTHOR]