Publications

Qin, ZF; Liao, H (2024). Observation-Constrained Climate Change in China over 1850-2014 by Aerosols in CMIP6 Models. JOURNAL OF CLIMATE, 37(24).

Abstract
Aerosols play a very important role in climate change with large uncertainties. Using the multimodel results from CMIP6, we analyzed the aerosol effective radiative forcing (ERF) and aerosol-induced surface air temperature (SAT) change in China in the present day (PD;11-yr mean of 2004-14) relative to the preindustrial (PI) time (11-yr mean of 1850-60). With the increase in the anthropogenic emissions, the simulated surface PM 2.5 concentration and aerosol optical depth (AOD) averaged over eastern China (EC; 18 degrees-44 degrees N, 103 degrees-122 degrees E) increased by 21.43 +/- 7.58 mu g m-3 and 0.47 +/- 0.33, respectively, from PI to PD. The simulated aerosol ERFs in EC were-4.91 +/- 2.56 and-5.35 +/- 2.40 W m-2 from equilibrium and transient simulations, respectively. The simulated change in SAT caused by the increases in aerosols was-1.37 degrees +/- 0.38 degrees C in EC from PI to PD. The simulated values of equilibrium and transient climate sensitivity to aerosols (CSA; aerosol-induced SAT change per unit aerosol ERF) in EC were 0.236 degrees and 0.222 degrees C (W m-2 )-1 , respectively. By using the observed AOD from MODIS to constrain aerosol ERF, the constrained aerosol equilibrium and transient ERFs over EC were-4.66 and-4.93 W m-2, respectively, which were smaller in magnitude than the simulated values directly from the models. By using the observed SAT from the Climatic Research Unit temperature version 5 to constrain aerosol- induced cooling, the surface cooling caused by aerosols was magnified to-1.47 degrees C. The adjusted CSA after the constraint was calculated by dividing adjusted aerosol-induced SAT change by adjusted aerosol ERF. Adjusted equilibrium and transient CSA values in EC were 0.32 degrees and 0.34 degrees C (W m-2 )-1 , respectively.

DOI:
10.1175/JCLI-D-24-0204.1

ISSN:
0894-8755