A High CO Episode of Long-Range Transport Detected by MOPITT

Recent developments in satellite remote sens- ing technologies resulted in the ability to observe major pollution events such as dust and smoke around the world on a daily basis. Satellite imagery can sometimes detect long-range transport episodes. In this paper, a high CO episode at remote GAW station, Mt. Waliguan, detected by MOPITT CO dataset during the end of April 2002, is described. CO concentrations above 600 hPa almost doubled on 27 April and CMDL surface sample mea- surements also observed this significant CO enhance- ment. Using NCEP data, satellite fire products data and backward trajectory model we suggest that this high CO episode of 27 April is not a local pollution event, but that it is due to long-range transport from active biomass burning and biofuel burning areas located in the border areas of PakistanandIndia. Thetrajectory cluster analysis shows that the origins of 5-day backward trajectories, for