Towards a combined SAGE II and SCIAMACHY aerosol dataset and implications for stratospheric aerosol trend analysis over East Asia
Scanning Imaging Absorption Spectrometer for Atmospheric Cartography (SCIAMACHY) limb observation data are used to retrieve stratospheric aerosol extinction profiles. The retrieved aerosol profiles are compared with Stratospheric Aerosol and Gas Experiment (SAGE) II aerosol data records. The comparisons are made over the period 2003–2004. The results show that the SCIAMACHY aerosol profile retrievals exhibit general agreement with the coincident SAGE II data records. In the 15–35 km altitude range, the percentage differences between the SCIAMACHY-retrieved and SAGE II–measured zonal mean aerosol extinction profiles are less than 20% for the 20–30°N and 30–40°N latitude zones, and less than 25% for the 40–50°N zone. The stratospheric aerosol optical depths in this altitude range calculated from SCIAMACHY retrievals are in good agreement with SAGE II measurements, with present differences less than 6% for the three latitude zones. The aerosol retrievals from SCIAMACHY observations are combined with the SAGE II aerosol data records, form a long-term data-set for the period 2000–2010. Using the combined SAGE II and SCIAMACHY data-set, the variation trends of the stratospheric aerosol layer over East Asia (20–50°N, 70–150°E) are analyzed. The results indicate that the stratospheric aerosols have a significant trend of increase over East Asia during 2000–2010. The stratospheric aerosol optical depths increase by about 5% per year over the 11-yr period. The increase in stratospheric aerosols is found to be obviously related to moderate volcanic eruptions.
利用SCIAMACHY临边探测资料反演出平流层气溶胶消光系数廓线。将2003–2004年SCIAMACHY气溶胶反演结果同SAGE II探测结果进行对比,结果表明在15–35 km 高度范围,反演结果在20–30°N和30–40°N范围平均相对偏差小于20%,在40–50°N范围小于25%。计算出的平流层气溶胶光学厚度与SAGE II探测结果的相对偏差在3个纬度范围均小于6%。将SCIAMACHY反演结果与SAGE II探测资料相结合,构建平流层气溶胶长期探测资料。根据这些资料,分析东亚(20–50°N,70–150°E)平流层气溶胶变化趋势。结果表明东亚平流层气溶胶在 2000–2010年期间呈现显著增加趋势。平流层气溶胶光学厚度在这11年期间平均每年增加5%。中等强度火山爆发对平流层气溶胶增加有显著影响。