Dataset in support of PhD thesis - Investigating radiative adjustments to anthropogenic aerosol perturbations using novel modelling techniques

1. ABOUT THE DATASET------------ Title: Investigating radiative adjustments to anthropogenic aerosol perturbations using novel modelling techniques - PhD Thesis Creator(s): Max R. Coleman (https://orcid.org/0000-0002-5709-6141) Organisation(s): University of Reading, Met Office Rights-holder(s): University of Reading Publication Year: 2025 Description: This dataset contains data output from the UK Earth System Model 1 (UKESM1) using Unified Model (UM) version 11.1 and SOCRATES radiative transfer codes, produced in support of research into radiative adjustments arising from anthropogenic aerosol radiative adjustments, focused on the use of nudging and the Partial Radiative Perturbation technique. The dataset includes various outputs, including: radiative flux fields, aerosol concentrations, radiatively active climate variables (e.g. albedo, clouds, temperature, specific humidity), horizontal wind and potential temperature diagnostics for nudging, and diagnostics from the UM nudging code from UKESM1; and inputs from UKESM1 to the SOCRATES radiative transfer codes as well as radiative flux outputs from SOCRATES. All data originates from fixed SST experiments and is from a number of perturbation experiments, perturbing either black carbon or sulphate aerosol emissions and varying different nudging parameters, following the fixed SST approach (see Hansen et al 2005). Cite as: Coleman, Max R. (2025): 'Dataset in support of PhD thesis - Investigating radiative adjustments to anthropogenic aerosol perturbations using novel modelling techniques'. University of Reading. Dataset. Related publications: Coleman, Max R. (2024): 'Investigating radiative adjustments to anthropogenic aerosol perturbations using novel modelling techniques'. PhD Thesis. University of Reading. Coleman, M., Collins., W. J., Shine, K. P., Bellouin, N., O’Connor, F. M., Dalvi, M.. Significant effects of model nudging on cloud radiative adjustments under aerosol perturbations in UKESM1. Manuscript in preparation. Contact: [e-mail] Acknowledgements: Thanks go to my PhD supervisors - William J. Collins, Keith P. Shine, Nicolas Bellouin, Fiona M. O'Connor - and to my Met Office collaborators - Mohit Dalvi and James Manners - without whom this work would not have been possible. 2. TERMS OF USE------------ Copyright 2025 University of Reading. This dataset is licensed under a Creative Commons Attribution 4.0 International Licence: https://creativecommons.org/licenses/by/4.0/. 3. PROJECT AND FUNDING INFORMATION------------ Title: Investigating radiative adjustments to anthropogenic aerosol perturbations using novel modelling techniques, PhD project Dates: 09-2019 - 03-2024 Funding organisation: Scenario NERC Doctoral Training Partnership (NE/S007261/1); Met office (via CASE funding) 4. CONTENTS------------ The dataset is split primarily into folders with data concerning specific atmospheric variables. There are also folders related to specific aspects of the work, including nudging and socrates. Within each folder there are data output from a number of different fSST UKESM1 experiments, each experiment denoted by 'u-' followed by a 5 digit ID (e.g. u-br793). The setup for each experiment is listed below as well as in an .xlsx file in the dataset. The SOCRATES folder also contains data output from the offline SOCRATES radiation codes. Generally the data in most folders are multiannual (time) means or monthly means. However, the net_flux, nudging, and socrates folders contain an assortment of different data. The net_flux folder contains TOA fluxes from single experiments; differences between TOA fluxes from experiments (i.e. radiative forcing); and often these are also separated into all, clear, clean, clearclean, aerosol direct radative effect (DRE) and cloud radiative effect (CRE) sky types, which are calculated following the decomposition outlined in Ghan (2012). The data from nudging experiments is either .pp files produced from UKESM1 experiments, .nc files generated from processing of the .pp data, and some other data. The data from SOCRATES work is either .pp files from UKESM1 experiments (used as input to SOCRATES), or netCDF files using file extensions unique to variables (input variables or output flux fields). Experiments:Suite ID G Lower ramp Upper ramp Lvls Species Nudging Type Temporal Resolution Other NotesU-br793 n/a 4 2 10–83 control Free 6 hour input U-cd964 n/a 4 2 10–83 control Free 6 hour input 1M cycles and SOCRATES diagsU-cq059 n/a 4 2 10–83 control Free 6 hour input DEPRECATED; Was using to test bicgstab issue related to corrupted bc292 fileU-cj204 n/a 4 2 10–83 control Free 6 hour input DEPRECATEDU-bv046 n/a 4 2 10–83 SU Free 6 hour input U-cm885 n/a 4 2 10–83 SU Free 6 hour input 1M cycles and SOCRATES diagsU-cd559 n/a 4 2 10–83 BC Free 6 hour input DEPRECATED; 1M cycles and SOCRATES diagsU-ce067 n/a 4 2 10–83 BC Free 6 hour input U-co464 n/a 4 2 10–83 BC Free 6 hour input DEPRECATED; 1M cycles and SOCRATES diagsU-db548 n/a 4 2 10–83 BC Free 6 hour input 1M cycles and SOCRATES diagsU-bw477 1/6 4 2 10–83 control u v theta 6 hour input DEPRECATED; testing suiteU-bw797 1/6 4 2 10–83 control u v theta 6 hour input DEPRECATED; copy of existing suite for making my own suiteU-bw842 1/6 4 2 10–83 control u v theta 6 hour input Using N48 spatial resolution nudging inputU-by762 1/6 4 2 10–83 control u v theta 6 hour input Using N48 spatial resolution nudging inputU-by937 1/6 4 2 10–83 control u v theta 6 hour input Forgot to process beyond 2014 nudging input; when restart didn't run postproc or housekeeping until after 20151001 atmos_main time step (and preceding) done - meant all postproc adn housekeeping after 20150101 waiting, but probs okayU-bz236 1/12 4 2 10–83 control u v theta 6 hour input U-bz237 1/3 4 2 10–83 control u v theta 6 hour input U-bz380 1/6 4 2 10–83 control u v theta 6 hour input No copygrid (uses old interpolation?)U-bz528 1/1 4 2 10–83 control u v theta 6 hour input U-bz529 1/24 4 2 10–83 control u v theta 6 hour input U-by965 1/6 4 2 10–83 SU u v theta 6 hour input Forgot to process beyond 2014 nudging input; when restart didn't run postproc or housekeeping until after 20151001 atmos_main time step (and preceding) done - meant all postproc adn housekeeping after 20150101 waiting, but probs okayU-bz234 1/12 4 2 10–83 SU u v theta 6 hour input U-bz235 1/3 4 2 10–83 SU u v theta 6 hour input U-bz381 1/6 4 2 10–83 SU u v theta 6 hour input No copygrid (uses old interpolation?)U-bz526 1/1 4 2 10–83 SU u v theta 6 hour input U-bz527 1/24 4 2 10–83 SU u v theta 6 hour input U-bz531 1/6 4 2 10–83 control u v 6 hour input U-ca680 1/1 4 2 10–83 control u v 6 hour input U-ca681 1/3 4 2 10–83 control u v 6 hour input U-ca682 1/12 4 2 10–83 control u v 6 hour input U-ca683 1/24 4 2 10–83 control u v 6 hour input U-cb530 1/6 4 2 10–83 SU u v 6 hour input U-ca684 1/1 4 2 10–83 SU u v 6 hour input U-ca685 1/3 4 2 10–83 SU u v 6 hour input U-ca686 1/12 4 2 10–83 SU u v 6 hour input U-ca687 1/24 4 2 10–83 SU u v 6 hour input U-cd563 1/6 4 2 10–83 BC u v theta 6 hour input U-cb470 1/6 4 2 10–83 BC u v 6 hour input U-cb108 1/6 1 2 1–83 control u v theta 6 hour input U-cb110 1/6 4 2 1–83 control u v theta 6 hour input U-cf764 1/1 1 2 1–83 control u v theta 6 hour input U-ch277 1/6 1 2 1–83 control u v theta 3 hour input U-ch425 1/6 1 2 1–83 control u v theta 1 hour input U-ch999 1/3 1 2 1–83 control u v theta 3 hour input U-ci119 1/3 1 2 1–83 control u v theta 1 hour input U-cj765 1/6 1 2 0–83 control u v theta 6 hour input Copy of u-cb108 with nudging set to Lvls 0–83, with change to branch to allow bottom level nudgingU-cb109 1/6 1 2 1–83 SU u v theta 6 hour input U-cb111 1/6 4 2 1–83 SU u v theta 6 hour input U-cf765 1/1 1 2 1–83 SU u v theta 6 hour input U-ch278 1/6 1 2 1–83 SU u v theta 3 hour input U-ch424 1/6 1 2 1–83 SU u v theta 1 hour input U-ci000 1/3 1 2 1–83 SU u v theta 3 hour input U-ci120 1/3 1 2 1–83 SU u v theta 1 hour input U-cj766 1/6 1 2 0–83 SU u v theta 6 hour input Copy of u-cb109 with nudging set to Lvls 0–83, with change to branch to allow bottom level nudgingU-ce303 1/6 1 2 1–83 BC u v theta 6 hour input U-cb349 1/6 1 2 1–83 control u v 6 hour input U-cb351 1/6 4 2 1–83 control u v 6 hour input U-cb350 1/6 1 2 1–83 SU u v 6 hour input U-cb352 1/6 4 2 1–83 SU u v 6 hour input U-ce304 1/6 1 2 1–83 BC u v 6 hour input Key:Suite ID - ID of experimentG - relaxation parameter for nudgingLower ramp - number of levels upwards from lowest level nudged to increase the nudging relaxation parameter from 0 to GUpper ramp - number of levels downwards from highest level nudged to increase the nudging relaxation parameter from 0 to GLvls - model levels over which nudging was appliedSpecies - whether the experiment represents a control (all emissions 2014), sulphate (SU) perturbed (anthropogenic sulphate emissions set to 1850 levels) or black carbon (BC) perturbed (anthropogenic and biomass burning black carbon emissions set to 1850 levels) experimentNudging type - whether non-nudged (Free), nudging horizontal wind fields (u v) or nudging horizontal winds and potential temperature fields (u v theta)Temporal Resolution - time interval of nudging inputOther notes - other notes about experiment or reason for experiment for non main experiments 5. METHODS----------- Code used to process the data and produce figures can mostly be found at https://doi.org/10.5281/zenodo.15690941 (nudging analysis code) or https://doi.org/10.5281/zenodo.15689941 (Socrates analysis code). However, code for conducting the experiments is not recorded here due to proprietary and other constraints, but includes use of the UKESM1 and SOCRATES as well as processing scripts using NCO (netCDF Climate Operators) and the Cylc workflow engine for running and processing inputs/outputs to/from SOCRATES. All UKESM1 experiments were atmosphere-only (with UKCA) fSST experiments. See corresponding thesis and papers (above) for full methods.