Title: Dataset for the "Response of the Geospace System to the Solar Wind Dynamic Pressure Decrease on 11 June 2017: Numerical Models and Observations" Authors: Dogacan Su Ozturk, Shasha Zou, James A. Slavin, Aaron J. Ridley Date generated: 19 February 2018 Contact: dogacan.s.ozturk@jpl.nasa.gov Grant no: NSF Grant - AGS1400998 Full citation for the publication: Ozturk, D. S., Zou, S. , Ridley, A. J., & Slavin, J. A. (2019), The response of the Geospace System to the Solar Wind Dynamic Pressure Decrease on 11 June 2017: Numerical Models and Observations +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Research Overview: The global magnetosphere-ionosphere-thermosphere (M-I-T) system is intrinsically coupled and susceptible to external drivers such as solar wind dynamic pressure enhancements. On 11 June 2017, a sudden solar wind dynamic pressure decrease occurred at 1437 UT according to the OMNI solar wind data. The solar wind velocity did not change signicantly,while the density dropped from 42 cm^-3 to 10 cm^-3 in a minute. The IMF BZ was in weakly northward during the event, while the BY changed from positive to negative. Using the University of Michigan Block Adaptive Tree Solarwind Roe Upwind Scheme (BATS-R-US) global magnetohydrodynamics (MHD) code, the global responses to the decrease in the solar wind dynamic pressure were studied. The simulation revealed that the magnetospheric expansion consisted of two phases similar to the responses during magnetospheric compression, namely a negative preliminary impulse and a negative main impulse phase.The simulated plasma flow and magnetic fields reasonably reproduced the THEMIS and MMS spacecraft in situ observations. Two separate pairs of dawn-dusk vortices formed during the expansion of the magnetosphere, leading to two separate pairs of Field-Aligned Current (FAC) cells. The effects of the flow and auroral precipitation on the I-T system were investigated using the Global Ionosphere Thermosphere Model (GITM) driven by simulated ionospheric electrodynamics. The perturbations in the convection electric fields caused enhancements in the ion and electron temperatures. This study shows that, like the well-studied sudden solar wind pressure increases, sudden pressure decreases can have large impacts in the coupled I-T system. In addition, the responses of the I-T system depend on the initial convection flows and FAC profiles before the solar wind pressure perturbations. Key Points: - The decrease in the solar wind dynamic pressure led to two separate pairs of oppositely rotating vortices in the dawn and dusk. - FACs accompanied each magnetospheric vortex and altered the ionosphere convection patterns. - Joule heating increased in the regions sandwiched by the perturbation FACs, leading to increased ion temperatures. +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Methods: We used the Global Magnetosphere (GM), Inner Magnetosphere (IM) and Ionospheric Electrodynamics (IE) modules of the Space Weather Modeling Framework (SWMF) (Toth et al., 2005). The global MHD code Block Adaptive Tree Solar Wind Roe Upwind Scheme (BATS-R-US) was used in the GM region to solve for the ideal MHD equations and was coupled with the IM and IE components (Powell et al., 1999; Toth et al., 2005; Ridley et al., 2016). The IE component was the Ridley Ionosphere Model (RIM) (Ridley et al., 2004), which was driven by the FACs and auroral power computed from the GM component and estimated the ionospheric electric potential based on FACs and conductance. The potential solution was then mapped out to the GM inner boundary at 2.5 Re where it was used to drive the motion of the magnetic field lines in BATS-R-US. The results obtained from the coupled GM-IM-IE modules including convection and auroral precipitation were used to drive the Global Ionosphere Thermosphere Model (GITM) (Ridley, et al., 2006). GITM is a three-dimensional, parallel, spherical code that uses a stretched altitude grid and allows non-hydrostatic solutions (Ridley et al., 2006). The model self-consistently solves the electron, ion and neutral temperatures (Zhu & Ridley, 2016). For this study, we used a spatial resolution of 4 degree in longitude to 1 degree in latitude for the region between ~100 km to ~600 km. The GITM simulation was also driven by the same solar wind and IMF conditions that was used to run SWMF, to specify the ionospheric potentials according to the Weimer model (2005) and the auroral power according to the Ovation model (2002), from 09/06/2017-0000 UT, i.e., two days before the event, to 11/06/2017-1400 UT, i.e., ~10 minutes before the decompression. From 1405 UT onwards, we used the electric potentials and auroral powers obtained from the MHD simulation to drive the GITM model, updating the electrodynamic patterns every 10 seconds to better capture the temporal and spatial variations associated with the solar wind drivers. The simulation data were generated through the use of the following models: the Block Adaptive Tree Solarwind Roe Upwind Scheme (BATS-R-US), Rice Convection Model (RCM), Ridley Ionosphere Model (RIM) and the Global Ionosphere Thermosphere Model (GITM). The simulations were performed on the Cheyenne Supercomputer Clusters provided by National Center for Atmospheric Research (NCAR) Computational and Information Systems Laboratory, sponsored by the National Science Foundation. References: Powell, K. G., P. L. Roe, T. J. Linde, T. I. G 651 ombosi, D. L. De Zeeuw (1999), A Solution Adaptive Upwind Scheme for Ideal Magnetohydrodynamics, Journal of Computational Physics, 154, 284-309, doi:10.1006/jcph.1999.6299 Ridley, A. J., Gombosi, T. I., & DeZeeuw, D. L. (2004). Ionospheric control of the magnetosphere: conductance. Annales Geophysicae, 22 , 567-584, https://doi.org/10.5194/angeo-22-567-2004. Ridley, A. J., Y. Deng, G. Toth (2006), The global ionosphere-thermosphere model (GITM), Journal of Atmospheric Solar-Terrestrial Physics, 68, 839-864 Toffoletto, F., Sazykin, S., Spiro, R., & Wolf, R. (2003). Inner magnetospheric modeling with the rice convection model. Space Science Reviews, 107 , 175-196, https://doi.org/10.1023/A:1025532008047. Toth, G., Sokolov, I. V., Gombosi, T. I., Chesney, D. R., Clauer, C. R., DeZeeuw, D. L., . . . Yu, B. (2005). Space weather modeling framework: A new tool for the space science community. Journal of Geophysical Research, https://doi.org/10.1029/2005JA011126. Weimer, D. R. (2005). Predicting surface geomagnetic variations using ionospheric electrodynamic models. Journal of Geophysical Research, https://doi.org/10.1029/2005JA011270. Zhu, J., and A. J. Ridley (2016), Investigating the 753 performance of simplified neutral-ion collisional heating rate in a global IT model, Journal of Geophysical Research Space Physics, 121, 578–588, doi:10.1002/2015JA021637 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Model Information: Information on the models used can be found at http://csem.engin.umich.edu/tools/ SWMF/BATS-R-US/RIM: http://csem.engin.umich.edu/tools/swmf/ RCM: https://ccmc.gsfc.nasa.gov/models/modelinfo.php?model=RCM GITM: https://github.com/aaronjridley/GITM Weimer: https://ccmc.gsfc.nasa.gov/models/modelinfo.php?model=Weimer OvationPrime: https://ccmc.gsfc.nasa.gov/models/modelinfo.php?model=Ovation%20Prime +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ File Inventory: This repository contains: - 3D Tecplot binary files from coupled SWMF simulations between 1435-1457 UT (*.plt) - 3D IDL binary files from GITM simulations between 1435-1457 UT (*.bin) - 2D ascii files from IE/RIM component between 1435-1457 UT (*.idl) - 2D ascii files from virtual magnetometers in the SWMF simulations between 1435-1457 UT (*.out) - 1D ascii files from virtual satellites in the SWMF simulations between 1435-1457 UT (*.sat) - Readme file Definition of Terms and Variables: The global magnetosphere-ionosphere-thermosphere (M-I-T) system is intrinsically coupled and susceptible to external drivers such as solar wind dynamic pressure variations. In order to understand the large-scale dynamic processes in the M-I-T system due to the decompression associated with the solar wind dyanmic pressure drops, the 11 June 2017 event was studied in detail using global numerical models. This data set is comprised of the simulation data generated from these models. Contents of 3d__mhd_FORMAT.bin and similar files MHD - vars: X Y Z rho Ux Uy Uz Bx By Bz P Jx Jy Jz X: x coordinate Y: y coordinate Z: z coordinate rho: density Ux: x-component of velocity Uy: y-component of velocity Uz: z-component of velocity Bx: x-component of magnetic field By: y-component of magnetic field Bz: z-component of magnetic field P: pressure Jx: x-component of the current Jy: y-component of the current Jz: z-component of the current Contents of itFORMAT.idl and similar files "Theta [deg]","Psi [deg]" "SigmaH [S]","SigmaP [S]" "JR [`mA/m^2]","PHI [kV]" "E-Flux [W/m^2]" "Ave-E [eV]" "RT 1/B [1/T]","RT Rho [amu/cm^3]","RT P [Pa]" "JouleHeat [mW/m^2]" "IonNumFlux [/cm^2/s]" "conjugate dLat [deg]" "conjugate dLon [deg]" Contents of mag_grid_FORMAT.out and similar files Lon Lat dBn dBe dBd dBnMhd dBeMhd dBdMhd dBnFac dBeFac dBdFac dBnHal dBeHal dBdHal dBnPed dBePed dBdPed Lon: Magnetic longitude Lat: Magnetic latitude dBn: N-component of total magnetic perturbation (north) dBe: E-component of total magnetic perturbation (east) dBd: D-component of total magnetic perturbation (horizontal) Mhd: Contribution from magnetospheric currents Fac: Contribution from FAC currents Hal: Contribution from Hall currents Ped: Contribution from Pedersen currents Contents of 3DALL_FORMAT.bin and similar files Altitude: Altitude from the surface of the planet (m) Ar: Argon density (m-3) Ar Mixing Ratio: Argon mixing ratio CH4 Mixing Ratio: Methane mixing ratio Conduction: Heat conduction EuvHeating: EUV Heating rate H: Hydrogen density (m-3) H!U+!N: H+ density (m-3) H2 Mixing Ratio: Molecular Hydrogen mixing ratio HCN Mixing Ratio: Hydrogen Cyanide mixing ratio He: Helium density (m-3) He!U+!N: He+ density (m-3) Heaing Efficiency: Heating efficiency Heat Balance Total: Heat balance total Latitude: Geographic latitude (degrees) Longitude: Geographic longitude (degrees) N!D2!N: N2 density (m-3) N!D2!U+!N: N+2 density (m-3) N!U+!N: N+ density (m-3) N(!U2!ND): N(2D) density (m-3) N(!U2!NP): N(2P) density (m-3) N(!U4!NS): N(4S) density (m-3) N2 Mixing Ratio: Molecular nitrogen mixing ratio NO: Nitrious Oxide density (m-3) NO!U+!N: NO+ density (m-3) O!D2!N: O2 density (m-3) O!D2!U+!N: O+2 density (m-3) O(!U1!ND): O(1D) density (m-3) O(!U2!ND)!U+!N: O(2D) density (m-3) O(!U2!NP)!U+!N: O(2P) density (m-3) O(!U3!NP): O(3P) density (m-3) O 4SP !U+!N: O(4SP)+ density (m-3) RadCooling: Radiative Cooling rate Rho: Neutral density (m-3) Temperature: Neutral temperature (K) V!Di!N (east): Ion velocity towards geographic East (m s-1) V!Di!N (north): Ion velocity towards geographic North (m s-1) V!Di!N (up): Vertical ion velocity (m s-1) V!Dn!N (east): Neutral velocity towards geographic East (m s-1) V!Dn!N (north): Neutral velocity towards geographic North (m s-1) V!Dn!N (up): Vertical neutral velocity (m s-1) V!Dn!N (up,N!D2!N): Vertical N2 velocity (m s-1) V!Dn!N (up,N(!U4!NS)): Vertical N(4S) velocity (m s-1) V!Dn!N (up,NO): Vertical NO velocity (m s-1) V!Dn!N (up,O!D2!N): Vertical O2 velocity (m s-1) V!Dn!N (up,O(!U3!NP)): Vertical O(3P) velocity (m s-1) e-: electron density (m-3) eTemperature: electron temperature (K) iTemperature: ion temperature (K) time: Universal time Contents of sat_FORMAT.sat and similar files [GSM coordinates] Satellite data for Satellite: mms4_20170611.dat it year mo dy hr mn sc msc X Y Z Rho Ux Uy Uz Bx By Bz P b1x b1y b1z e jx jy jz theta1 phi1 status theta2 phi2 it: iteration number year: simulation year mo: simulation month dy: simulation day hr: simulation hour mn: simulation minute sc: simulation second msc: simulation milisecond X: x coordinate Y: y coordinate Z: z coordinate Rho: density Ux: velocity in x coordinate Uy: velocity in y coordinate Uz: velocity in z coordinate Bx: magnetic field in x coordinate By: magnetic field in y coordinate Bz: magnetic field in z coordinate P: pressure b1x: magnetic field perturbation in x coordinate b1y: magnetic field perturbation in y coordinate b1z: magnetic field perturbation in z coordinate e: charge jx: current density in x coordinate jy: current density in y coordinate jz: current density in z coordinate theta1: colatitude of mapped field line along B phi1: longitude of mapped field line along B status: field line topology theta2: colatitude of mapped field line along -B phi2: longitude of mapped field line along -B Omni Database: https://omniweb.gsfc.nasa.gov Solar wind density, velocity, y and z components of the Interplanetary Magnetic Field are downloaded from the OMNI Database for the studied interval. CDAWeb Database: https://cdaweb.sci.gsfc.nasa.gov/index.html/ THEMIS-D velocity data and MMS-1 magnetic field data are downloaded from CDAWeb database for the studied interval. +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Use and Access: The data provided in this repository is open to public access. Anyone can download and reuse the data. Restrictions apply for publishing with the data presented here. Please contact, author Dogacan Ozturk (dogacan.s.ozturk@jpl.nasa.gov) for further information and permission. +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Data citation: Please use the following format to cite the data directly. Ozturk, D.S. (2018). Dataset for the "Response of the Geospace System to the Solar Wind Dynamic Pressure Decrease on 11 June 2017: Numerical Models and Observations". University of Michigan Deep Blue Data Repository. https://doi.org/10.7302/Z26T0JW6 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++