Evaluation of long-term tropospheric NO2 data obtained by GOME over East Asia in 1996-2002

Abstract

Long-term tropospheric nitrogen dioxide (NO2) column data obtained by the Global Ozone Monitoring Experiment (GOME) (G-NO2) are evaluated to confirm the trends found in tropospheric NO2 abundances over East Asia between 1996 and 2002. For three locations in Central and East Asia, the G-NO2 values are compared with tropospheric columns estimated from coincident observations of total NO2 by ground-based UV/visible spectrometers and stratospheric NO2 by satellite solar occultation sensors (E-NO2). The comparisons show a slight linear drift in G-NO2 data from 1996 to 2002. However, it is much smaller than the standard deviation of the differences between G-NO2 and E-NO2 and much smaller than the increasing trends in NO2 seen by GOME over the industrial areas of China, demonstrating the validity of the trends estimated using the GOME data. Copyright 2005 by the American Geophysical Union.