LSMOD.2 - Global paleomagnetic field model for 50 -- 30 ka BP

Global spherical harmonic paleomagnetic field model LSMOD.2 describes the magnetic field evolution from 50 to 30 ka BP based on published paleomagnetic sediment records and volcanic data. It is an update of LSMOD.1, with the only difference being a correction to the geographic locations of one of the underlying datasets. The time interval includes the Laschamp (~41 ka BP) and Mono Lake (~34 ka BP) excursions. The model is given with Fortran source code to obtain spherical harmonic magnetic field coefficients for individual epochs and to obtain time series of magnetic declination, inclination and field intensity from 49.95 to 30 ka BP for any location on Earth. For details see M. Korte, M. Brown, S. Panovska and I. Wardinski (2019): Robust characteristics of the Laschamp and Mono lake geomagnetic excursions: results from global field models. Submitted to Frontiers in Earth Sciences



File overview:



LSMOD.2 -- ASCII file containing the time-dependent model by a list of spline basis knot points and spherical harmonic coefficients for these knot points.

LSfield.f -- Fortran source code to obtain time series predictions of declination, inclination and intensity from the model file.

LScoefs.f -- Fortran source code to obtain the spherical harmonic coefficients for an individual age from the time-dependent model file.



The data are licenced under the Creative Commons Attribution 4.0 International Licence (CC BY 4.0) and the Fortran Codes under the Apache License, Version 2.0.



The Fortran source code should work with any standard Fortran 77 or higher compiler. Each of the two program files can be compiled separately, all required subroutines are included in the files. The model file, LSMOD.1 or LSMOD.2, is read in by the executable program and has to be in the same directory. The programs work with interactive input, which will be requested when running the program.