Derivation of Hemispheric Ionospheric Current Functions From Ground-Level Magnetic Fields

These files provide the input and output data for the Figures shown in the paper "Derivation of<br> Hemispheric Ionospheric Current Functions From Ground-Level Magnetic Fields" by Daniel Weimer, published in the Journal of Geophysical Research, Space Physics, paper number 2018JA026191, doi:10.1029/2018JA026191 Two IDL program files and the original, PDF versions of the figures are included. The data are provided as IDL "SAVE" files, readable in IDL with the "RESTORE" command. NetCDF<br> versions are included, readable with any NetCDF software library. These NetCDF files have the same<br> names as the ".xdr" files, except they have the extension ".nc". Scalar variables (length 1) are put<br> into the Global Attributes in these files. The files in this archive are: Figures:<br> Figure_1.PDF<br> Figure_2.PDF<br> Figure_3.PDF<br> Figure_4.PDF<br> Figure_5.PDF<br> Figure_6.PDF IDL Programs:<br> spherical_cap_90_fits.pro : Routines for fitting magnetic field data on a hemispheric cap (90<br> degrees), using spherical harmonics having both internal and external sources (or external alone),<br> and functions for evaluating the results as equivalent currents, or the magnetic field components. AllLegendre.pro : Required by spherical_cap_90_fits.pro, provides computations of Associated<br> Legendre Polynominals as arrays, for all combinations of l and m, up to Lmax and Mmax, as well as first derivatives. Data Files: Figures_1_2_3_4_dB_ModelData.xdr : Magnetic field values (output from the 2013 empirical model),<br> shown in Figure 1, and used to calculate the coefficients used to make Figures 2, 3, and 4.<br> Contents:<br> ALLLATS FLOAT = Array[8640] , array of latitude values, degrees<br> ALLMLTS FLOAT = Array[8640] , array of Magnetic Local Time (MLT) values, hours<br> DBNS FLOAT = Array[8640] , array of northward magnetic field values<br> DBES FLOAT = Array[8640] , array of eastward magnetic field values<br> DBVS FLOAT = Array[8640] , array of vertical (downward) magnetic field values<br> NLATS FLOAT = 180.000<br> NMLTS INT = 48<br> empirical model inputs:<br> BT FLOAT = 10.0000 , magnitude of the IMF<br> ANGLE FLOAT = 180.000 , IMF clock angle<br> F107 FLOAT = 120.000 , F10.7 solar index<br> SWVEL FLOAT = 400.000 , solar wind velocity<br> TILTA FLOAT = 0.00000 , dipole tilt angle Figures_2_3_4_SCHA90FitResults.xdr : The coefficients obtained from the fits, used to generate<br> Figures 2, 3, and 4.<br> Contents:<br> SPHCE DOUBLE = Array[115] , external spherical harmonic coefficients<br> SPHCI DOUBLE = Array[115] , interal spherical harmonic coefficients<br> NOINT_SPHCE DOUBLE = Array[115] , external spherical harmonic coefficients,<br> derived without using the internal terms in the fitting of the magnetic potential<br> The following variables are documented in the IDL program spherical_cap_90_fits.pro:<br> MAXL INT = 34<br> MAXM INT = 3<br> ODD INT = 1<br> EVEN INT = 0<br> CSIZE INT = 115<br> LS INT = Array[115]<br> MS INT = Array[115]<br> AB BYTE = Array[115] Figures_3_4_dB_ModelData-Dst.xdr : Magnetic field values, after subtraction of the ring current<br> magnetic field, used to calculate the coefficients to make Figures 3 and 4.<br> Contents: Same variables as in file Figures_1_2_3_4_dB_ModelData.xdr Figures_3_4_SCHA90FitResults-Dst.xdr : The coefficients obtained from fitting the magnetic field<br> that had the ring current subtracted, used to make Figures 3, and 4.<br> Contents: Same variables as in file Figures_2_3_4_SCHA90FitResults.xdr Figure_5_dB_ModelDataTilt3x-Dst.xdr : eight sets of magnetic field values, after subtraction of the<br> ring current magnetic field, used to calculate the coefficients to generate Figure 5.<br> Contents: Similar variables as in file Figures_1_2_3_4_dB_ModelData.xdr, except that TILTA is<br> replaced by TILTS, an array with the eight dipole tilt angles. The magnetic field values are<br> replaced by these arrays:<br> DBN3X FLOAT = Array[180, 48, 3] , northward magnetic field, eight sets<br> DBE3X FLOAT = Array[180, 48, 3] , eastward magnetic field, eight sets<br> DBV3X FLOAT = Array[180, 48, 3] , vertical magnetic field, eight sets Figure_5_SCHA90FitResultsTilt3x-Dst.xdr : eight sets of coefficients obtained from fitting the<br> magnetic field, used to make Figure 5.<br> Contents: Same variables as in file Figures_2_3_4_SCHA90FitResults.xdr, except for these arrays:<br> SPHCE3X DOUBLE = Array[115, 3] , external spherical harmonic coefficients, eight sets<br> SPHCI3X DOUBLE = Array[115, 3] , internal spherical harmonic coefficients, eight sets Figure_6_dB_ModelDataClock8x-Dst.xdr : Eight sets of magnetic field values, after subtraction of<br> the ring current magnetic field, used to calculate the coefficients to generate Figure 6.<br> Contents: Similar variables as in file Figures_1_2_3_4_dB_ModelData.xdr, except that ANGLE is<br> replaced by ANGLES, an array with the eight IMF clock angles. The magnetic field values are<br> replaced by these arrays:<br> DBN8X FLOAT = Array[180, 48, 8] , northward magnetic field, eight sets<br> DBE8X FLOAT = Array[180, 48, 8] , eastward magnetic field, eight sets<br> DBV8X FLOAT = Array[180, 48, 8] , vertical magnetic field, eight sets Figure_6_SCHAFitResultsClock8x-Dst.xdr : Eight sets of coefficients obtained from fitting the<br> magnetic field, used to make Figure 6.<br> Contents: Same variables as in file Figures_2_3_4_SCHA90FitResults.xdr, except for these arrays:<br> SPHCE8X DOUBLE = Array[115, 8] , external spherical harmonic coefficients, eight sets<br> SPHCI8X DOUBLE = Array[115, 8] , internal spherical harmonic coefficients, eight sets<br>