DOI: 10.5061/dryad.5qfttdzgg
title: Fractional change of scattering and absorbing aerosols contributes to Northern Hemisphere Hadley Circulation expansion

description: This dataset contains the original monthly outputs simulated by CESM1.2.2
 forced by aerosol mass concentration fields derived from MERRA-2. The
 atmosphere component is CAM4, and the ocean component is slab ocean model.
 For more details of experiment design, see the original article.
description: Original monthly outputs simulated by CESM1.2.2 CAM4-SOM forced
 by aerosols derived from MERRA-2.
description: # Fractional change of scattering and absorbing aerosols contributes to
 Northern Hemisphere Hadley Circulation expansion
 [https://doi.org/10.5061/dryad.5qfttdzgg](https://doi.org/10.5061/dryad.5qfttdzgg) ## Description of the data and file structure These files includes the original monthly output data of CESM1.2.2 CAM4-SOM aerosol forcing experiments. Detailed description of the experiment design can be found at Ying et al, 2024, 'Fractional change of scattering and absorbing aerosols contributes to Northern Hemisphere Hadley Circulation expansion'. ### Files #### File: E2000\_aer\_aod1721-ssa1721\_merra2.rar **Description:** This simulation was forced by the aerosol mass cencentration fields derived from MERRA-2 averaged from 2017 to 2021. Please ignore the data of the first two years, since they are the same as the following two years. #### File: E2000\_aer\_aod1721-ssa8084\_merra2.rar **Description:** This simulation was forced by the aerosol mass cencentration fields derived from MERRA-2. The aerosol mass concentration fields were scaled so that the AOD was set to the mean state of 2017-2021, while the SSA was set to the mean state of 1980-1984. #### File: E2000\_aer\_aod8084-ssa1721\_merra2.rar **Description:** This simulation was forced by the aerosol mass cencentration fields derived from MERRA-2. The aerosol mass concentration fields were scaled so that the AOD was set to the mean state of 1980-1984, while the SSA was set to the mean state of 2017-2021. #### File: E2000\_aer\_aod8084-ssa8084\_merra2.rar **Description:** This simulation was forced by the aerosol mass cencentration fields derived from MERRA-2 averaged from 1980 to 1984. Please ignore the data of the first two years, since they are the same as the following two years. #### File: E2000\_ghg0804-aod8084-ssa8084\_merra2.rar **Description:** Similar to other simulations, but for GHGs were set to 1980-1984 level. The file name was set to '0804' by mistake and please ignore that. #### File: E2000\_ghg1721-aod1721-ssa1721\_merra2.rar **Description:** Similar to other simulations, but for GHGs were set to 2017-2021 level with aerosols of 2017-2021. #### File: E2000\_ghg1721-aod8084-ssa8084\_merra2.rar **Description:** Similar to other simulations, but for GHGs were set to 2017-2021 level with aerosols of 1980-1984. ### **Description of file structure:** Each of the rar file contains the original CESM output of one simulation. Each subfolder in '$CASENAME/archive/' contains the output of one model component. 'atm', 'lnd', 'ice' and 'rof' represent atmosphere, land, sea ice and river run-off, respectively, whereas other model components are inactive and thus there's no output. The 'rest' subfolder contains the initial fields prepared for continuing the simulation. Since our experiments are run with slab ocean model, the sea surface temperature is included in the output of sea ice component, and there's no output data in the 'ocn' subfolder. Within each subfolder, the output data are contained in 'hist', for example the output of the atmosphere component CAM4 is in '$CASENAME/archive/atm/hist'. The 'log' folder contains the log file for the whole simulation, which is usually used for debug. The 'h0' netcdf files in '$CASENAME/archive/atm/hist' are monthly output, and the 'h1' files are daily output. ### **Description of variables:** Variables within each monthly output file includes meteorological variables (such as temperature 'T', zonal wind 'U', meridional wind 'V', pressure velocity 'OMEGA', sea level pressure 'PSL', specific humidity 'Q', variables related to cloud 'CLD...', and other commonly used variables)， radiation variables (for exapmle, net shortwave radiation at surface 'FSNS'), 3-d aerosol optical depth (such as 3-d aerosol optical depth at visible band 'AEROD_v_3d', 3-d optical depth of different aerosol species 'ODV_3d'), and coordinates (longitude 'lon', latitude 'lat', and variables for the vertical hybrid coordinate: 'p0', 'hyam', 'hybm', 'hyai', 'hybi', pressure at each hybrid level could be computed as: p=a*p0+b*ps). Variables in daily output files are precipitation, as well as temperature and wind vector at several pressure level. See attributes of all variables for detailed description.