Effects of aerosols on cloud and precipitation in East‐Asian drylands

Abstract

Extensive observational and numerical simulations have been performed to better characterize the role of aerosols in affecting the clouds and precipitation. However, due to the large uncertainties of aerosol property, the effect of aerosols on clouds and precipitation over the arid and semiarid region (briefly called ‘drylands’) of East Asia (EA) is still unclear. Basing on observations and model simulations from the Coupled Model Intercomparison Project Phase 5 (CMIP5), we investigated the aerosol's effects on the cloud properties and precipitation over the drylands of EA from 1850 to the present and projected forward to 2,300. It is found that, during 1850–2005, with the mean aerosol optical depth (AOD) over the drylands of EA increasing, the cloud droplet number concentration (CDNC) increases, while the cloud effective droplet radius (CEDR) decreases significantly at a rate of −0.40 μm·century−1. Besides, the cloud water path (CWP) and precipitation show slightly increasing trends with the AOD increasing. Additionally, the effect of aerosols on cloud properties is saturated when the AODs reach 0.21 and 0.15 over the arid region (AR) and semiarid region (SR), respectively. According to the prediction for the period 2006–2300, the AOD and CDNC tend to decline over the drylands of EA, while the CWP, CEDR and precipitation show increasing trends. Particularly, the aerosol, clouds and precipitation indicate more significant changes over the SR in EA during 2006–2300. In future research, there is an urgent need to quantify the contribution of aerosol‐cloud interaction to the precipitation change over the drylands of EA.

Spatial Heterogeneity of Aerosol Effect on Liquid Cloud Microphysical Properties in the Warm Season Over Tibetan Plateau

“…Aerosol directly scatters and absorbs shortwave and longwave radiation through radiative effect (Abdoul et al., 2020; Chylek & Wong, 1995; Penner et al., 1992; Y. Sun and Zhao, 2020), and indirectly affects cloud macro‐ and micro‐physical properties and precipitation processes as cloud condensation nucleus (CCN) and ice nucleus through microphysical effect (Garrett & Zhao, 2006; Liu et al., 2019; R. Luo et al., 2021; Rosenfeld, Sherwood, et al., 2014, Rosenfeld, Andreae, et al., 2014; Rotstayn, 1999; Twomey, 1977).…”

Aerosol characteristics in CMIP6 models' global simulations and their evaluation with the satellite measurements

“…Unlike the representative concentration pathways (RCP) of the CMIP5, the 6th phase SSPs incorporated additional attributes such as land, energy use, and economic activities along with the impact of emissions for respective scenarios (Eyring et al, 2016). Aerosol optical depth from CMIP GCMs had been used to understand the relationship of AA with the global water cycle (Boé, 2016; Lin et al, 2018; Monerie et al, 2022; Sanap et al, 2015; Sobel et al, 2019), their influence on clouds (Cherian & Johannes, 2020; Frey et al, 2017; Hua et al, 2020; Luo et al, 2021) and Asian aerosol dipole patterns (Ramachandran et al, 2022; Wang et al, 2021). Spatiotemporal variations of AA in CMIP5 and CMIP6 models in eastern central China report an underestimation of AOD that decreased from 40% (CMIP5) to 8% (CMIP6) in comparison with satellite AOD during 2000–2005 (Ali et al, 2022; Li et al, 2021).…”

Dust Aerosol Impacts on the Time of Cloud Formation in the Badain Jaran Desert Area

“…Many studies have investigated the influence of aerosols on cloud formation and development. Some studies divided aerosols into two types that act as cloud condensation nuclei (CCN) and ice nucleating particles (INP), and explored the effects of aerosols on cloud microphysical properties, which is referred as the aerosol microphysical effect (Luo et al., 2021; Twomey, 1977; Zhao et al., 2012). There are also studies that divided aerosols into absorbing and non‐absorbing types, and explored the changes of atmospheric thermal structure through aerosol radiative effects that can further affect the cloud formation and properties, which is referred as the aerosol radiative effect (Ackerman et al., 2000; Andreae et al., 2004; Sun & Zhao, 2020; Zhou et al., 2017).…”

“…The sixth annual report (AR6) of Intergovernmental Panel on Climate Change (IPCC) also pointed out that the impact of aerosols on clouds is one of the largest uncertainties in current weather forecast and climate change research (Forster et al, 2021).Many studies have investigated the influence of aerosols on cloud formation and development. Some studies divided aerosols into two types that act as cloud condensation nuclei (CCN) and ice nucleating particles (INP), and explored the effects of aerosols on cloud microphysical properties, which is referred as the aerosol microphysical effect (Luo et al, 2021;Twomey, 1977;Zhao et al, 2012). There are also studies that divided aerosols into absorbing and non-absorbing types, and explored the changes of atmospheric thermal structure through aerosol radiative effects that can further affect the cloud formation and properties, which is referred as the aerosol radiative effect (…”