Consistency of Tropospheric Water Vapor between Reanalyses and Himawari-8/AHI Measurements over East Asia

High spatiotemporal resolution radiances from the advanced imagers onboard the new generation of geostationary weather satellites provide a unique opportunity to evaluate the abilities of various reanalysis datasets to depict multilayer tropospheric water vapor (WV), thereby enhancing our understanding of the deficiencies of WV in reanalysis datasets. Based on daily measurements from the Advanced Himawari Imager (AHI) onboard the Himawari-8 satellite in 2016, the bias features of multilayer WV from six reanalysis datasets over East Asia are thoroughly evaluated. The assessments show that wet biases exist in the upper troposphere in all six reanalysis datasets; in particular, these biases are much larger in summer. Overall, we find better depictions of WV in the middle troposphere than in the upper troposphere. The accuracy of WV in the ERA5 dataset is the highest, in terms of the bias magnitude, dispersion, and pattern similarity. The characteristics of the WV bias over the Tibetan Plateau are significantly different from those over other parts of East Asia. In addition, the reanalysis datasets all capture the shift of the subtropical high very well, with ERA5 performing better overall.