Publications

Tao, Minghui; Chen, Liangfu; Wang, Zifeng; Tao, Jinhua; Che, Huizheng; Wang, Xinhui; Wang, Yang (2015). Comparison and evaluation of the MODIS Collection 6 aerosol data in China. JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES, 120(14), 6992-7005.

Abstract
Several important improvements have been made in recent Moderate Resolution Imaging Spectroradiometer (MODIS) Collection 6 aerosol retrievals, but few regional validations are conducted. We compared Deep Blue (DB) and Dark Target (DT) retrievals over China and evaluated their performance with ground observations. Sampling frequency of DB was much higher than that of DT, which was mainly caused by unavailable retrieval of DT in bright surface and heavy pollution conditions. It is found that merged aerosol optical depth (AOD) will miss some cases if it was determined only by vegetation density. Collocated comparison shows that DT AOD was substantially higher than DB with seasonal difference exceeding 0.3-0.4 over eastern China. However, when all available retrievals were considered, DT AOD was obviously lower than DB in all the seasons except spring due to their large difference in spatial coverage in high-AOD conditions. DB can well reveal spatial extent of the widespread haze pollution while there were few values in DT. More than one half of the situations with AOD>1.0 was missed by DT, which largely underestimated the common regional haze pollution in eastern China. Ground validations show that DT tended to overestimate the aerosol loading by underestimation of the surface contribution and single scattering albedo of aerosols. DB performed generally well with higher accuracy in northern China but exhibited obvious underestimation in northwestern and southern China. Despite of slight decrease in accuracy, DB retrievals with all quality enable a large increase in spatial coverage, especially when dense haze clouds existed.

DOI:
10.1002/2015JD023360

ISSN:
2169-897X