READ ME File For Dataset supporting the University of Southampton doctoral Thesis "Observational and simulation studies of the structure of Earth's magnetotail during periods of northward IMF" Dataset DOI: 10.5258/SOTON/D2646 ReadMe Author: Laura Fryer, University of Southampton, ORCID ID:0000-0002-5215-6942 This dataset supports the thesis entitled "Observational and simulation studies of the structure of Earth's magnetotail during periods of northward IMF" AWARDED BY: Univeristy of Southampton DATE OF AWARD: 2023 DESCRIPTION OF THE DATA This thesis uses the closed-source GUMICS-4 code. A GUMICS license was provided to the University of Southampton by the Finnish Meteorological Institute, Helsinki, Finland, to run the GUMICS-4 model locally. GUMICS-4 is also available open source at https://ccmc.gsfc.nasa.gov/models/GUMICSāˆ¼4-HC-1.11/ through the CCMC interface. All parameters that can be input into the open-source version of GUMICS are listed in each respective chapter of this thesis which could be used to recreate the runs described. (Note: The output of the GUMICS-CCMC code has not been verified against this output run directly with the GUMICS model). This dataset contains a movie created to support the description of the analysis in Chapter 4. Licence: Creative Commons Attribution CC-BY Related projects/Funders: LJF was supported by the UK's Science and Technology Facilities Council (STFC) through studentship ST/T506424/1 (2279917) Related publication: 1. 3D GUMICS Simulations of Northward IMF Magnetotail Structure (https://doi.org/10.1029/2023JA031317) 2. Observations of Closed Magnetic Flux Embedded in the Lobes During Periods of Northward IMF (https://doi.org/10.1029/2021JA029281) Date that the file was created: 09, 2023