An advection fog event response to future climate forcing in the 2030s-2080s:a case study for Shanghai

Fog may continue to inhibit industry in the future.Here,we focused on a specific advection fog event in Shanghai,China,and applied a pseudo global warming method to examine advection fog under the RCP8.5 highemission scenario.The method involved downscaling the future atmospheric conditions over the ensemble average of 19 global climate models from the fifth phase of the Coupled Model Intercomparison Project(CMIP5).We used the Weather Research and Forecasting Model coupled with a single-layer urban canopy model(WRF‒UCM)to run four sensitivity experiments and examined the advection fog and its relationship to changes in meteorological conditions.The results showed that:1)The advection fog event tended to remain in Shanghai despite global warming;2)advection fog will not change greatly in the future;however,the onset and dissipation times will change slightly;3)relative humidity(RH)locally increases prior to the onset of the advection fog,and decreases at the dissipating stage,despite the current and future experiments having the same RH initial and boundary conditions;4)a small increase in surface air temperature and an increase in RH contribute to the early advection fog onset,and vice versa.Windspeed facilitates the early onset and dissipation of advection fog.