Rapid transport of East Asian pollution to the deep tropics

摘要: Anthropogenic emissions from East Asia have in- creased over recent decades. These increases led to changes in atmospheric composition as far afield North America under the prevailing westerly winds. Here we show that, during Northern Hemisphere (NH) winter, pollution originating also directly affects deep tropics. We present observations of marked intra-seasonal variability anthropogenic tracer perchloroethene (C2Cl4) collected at two locations Borneo (117.84 E, 4.98 N and 118.00 4.22 N) NH winter 2008/2009. use trajectories calculated with Numerical Atmospheric-dispersion Modelling Environment that observed enhancements C2Cl4 mixing ra- tio are caused by rapid meridional transport, form "cold surges", relatively polluted Asian land mass. In these events air masses can move 35 4 days. then data Monitor- ing Atmospheric Composition Climate reanalysis which suggest high may contain levels pollutants carbon monoxide ozone approx- imately double typical "background" Borneo. addition strengthening transport north, cold surges enhance convection Southeast Asia, further trajectory calculations indicate subsequently be lifted tropical upper troposphere. This suggests a potentially important connec- tion between midlatitude sources very low stratosphere.