EGU21-2457
https://doi.org/10.5194/egusphere-egu21-2457
EGU General Assembly 2021
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.

Strong aerosol effects on cloud amount based on long-term satellite observations over the East Coast of the United States

Yang Cao1,2, Minghuai Wang1,2, Daniel Rosenfeld1,3, Yannian Zhu1,2, Yuan Liang1,2, Zhoukun Liu1,2, and Heming Bai4
Yang Cao et al.
  • 1Nanjiang University, Nanjing, China (caoyang@smail.nju.edu.cn)
  • 2Joint International Research Laboratory of Atmospheric and Earth System Sciences & Institute for Climate and Global Change Research, Nanjing University, China
  • 3Institute of Earth Sciences, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
  • 4Research Center for Intelligent Information Technology, Nantong University, China

Here we use 16-year satellite and reanalysis data in combination with a multivariate regression model to investigate how aerosols affect cloud fraction (CF) over the East Coast of the United States. Cloud droplet number concentrations (Nd), cloud geometrical thickness, lower tropospheric stability, and relative humidity at 950 hPa (RH950) are identified as major cloud controlling parameters that explain 97% of the variability in CF. Nd is shown to play an important role in regulating the dependence of cloud fraction on RH950. The observed annual-mean CF shows no significant trend due to the cancelation from the opposite trends in Nd and RH950. The multivariate regression model revealed that the decline in Nd alone would lead to a about 20% relative decline in CF. Our results indicate the significant aerosol effects on CF and suggest the need to account for pollution-induced cloud changes in quantifying cloud feedback based on long-term observations.

How to cite: Cao, Y., Wang, M., Rosenfeld, D., Zhu, Y., Liang, Y., Liu, Z., and Bai, H.: Strong aerosol effects on cloud amount based on long-term satellite observations over the East Coast of the United States, EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-2457, https://doi.org/10.5194/egusphere-egu21-2457, 2021.

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