Output from a model run of a modified version of WRF-Chem, which we refer to as WRF-Chem Volcano (WCV). At the time of submission of this dataset, these data were the basis of the modelling part of a paper in preparation, working title: "WRF-Chem modelling and TROPOMI observations of halogen chemistry within the plume of Etna's Christmas 2018 eruption". The code of WCV is maintained here. Development of this code will continue after the submission of this repository, This branch is a permanent record of the code as used to create this dataset. This is a simulation of the chemistry of the plume of the 2018 eruption of Mount Etna. This simulation includes bromine, chlorine and mercury chemistry. The time period covered is the 24-27 December, however please note that the author considers the first 24 hours of simulation to be "spin up", and that the modelled volcanic fluxes were assigned based on observations at midday on the 25th, and were not calibrated specifically for the 26th or 27th. "Run L2" refers the internal serial number assigned to this model run. Overview of files Output files: wrfout_d0*_YYYY-MM-DD_HH:MM:SS Output data is contained in NetCDF files. Each file contains hourly snapshots of the 3D simulation with fields for various parameters. Most of the 4D (three spatial dimensions and time) variables record modelled mixing ratios of various species (in units ppm). Many other variables are standard WRF-Chem output variables; please see WRF-Chem's documentation. If the meaning of a variable is unclear, please contact the author. Files are separated by model domain and by time. The "d0x" value specifies the model domain. Domain 1 is the full extent of the modelled area and has grid cells of 30 km × 30 km. Domains 2, 3, 4 each model a successively smaller area subset at a 3x greater resolution than their parent domain. Please see the ACPD paper for further details on this. For operational reasons, the number of hours in different output files is slightly irregular: Files wrfout_d0x_2018-12-24_00:00:00 contain 24 hourly snapshots from 2018-12-24_00:00:00 -- 2018-12-24_23:00:00 Files wrfout_d0x_2018-12-25_00:00:00 contain 24 hourly snapshots from 2018-12-25_00:00:00 -- 2018-12-25_23:00:00 Files wrfout_d0x_2018-12-26_00:00:00 contain 1 snapshot, 2018-12-26_00:00:00 only Files wrfout_d0x_2018-12-26_01:00:00 contain 24 hourly snapshots from 2018-12-26_01:00:00 -- 2018-12-27_00:00:00 Files wrfout_d0x_2018-12-27_01:00:00 contain 24 hourly snapshots from 2018-12-27_01:00:00 -- 2018-12-28_00:00:00 Input files This repository also contains various input files for the WRF-Chem simulation. wrfinput_d0x (netcdf format) defines the initial conditions assigned for the beginning of the simulation (2018-12-24 00:00:00) for each of the model domains. wrfbdy_d01 (netcdf format) defines the boundary conditions for the simulation. wrfchemi_d0x_YYYY-MM-DD_HH:MM:SS (netcdf format) defines, for each day and domain of the simulation, anthropogenic emissions. wrfchemv_d0x (netcdf format) defines the volcanic emissions. A file is specified for each domain. namelist.input (text file) defines various wrf-chem runtime options