This distribution contains the pfm9k geomagnetic field models and datafiles as presented in A. Nilsson, R. Holme, M. Korte, N. Suttie and M. Hill (2014): Reconstructing Holocene geomagnetic field variation: new methods, models and implications. Geophys. J. Int., doi: 10.1093/gji/ggu120. Please see this publication for details on the models


Files:

pfm9kfield.f - Fortran source code to predict time series of declination, inclination and intensity
pfm9kcoefs.f - Fortran source code to calculate model Gauss coefficients for a given time

pfm9k.1      - pfm9k.1 model coefficients
pfm9k.1a     - pfm9k.1a model coefficients
pfm9k.1b     - pfm9k.1b model coefficients with uncertainties

pfm9k.0_DAT  - Initial dataset, before outlier rejection and declination/intensity calibration
pfm9k.0a_DAT - Initial timescale adjusted dataset, before outlier rejection and declination/intensity calibration
pfm9k.1_DAT  - Final dataset used for pfm9k.1
pfm9k.1a_DAT - Final dataset used for pfm9k.1a (adjusted timescales for the sedimentary data)
pfm9k.1b_DAT - Final dataset used for pfm9k.1b


Each data file contains the following columns:

Age - Age of datum, or data bin for the sedimentary data.
sA  - Standard deviation of the age.
Abb - A three letters abbreviation of the lake name (See Nilsson et al. 2014, Table 1), all archaeomagnetic data are assigned with ”ARC”.
lat - Site latitude.
lon - Site longitude.
Dec - Declination between -180 and 180 degrees.
sD  - Standard error of the declination.
Inc - Inclination.
sI  - Standard error of the inclination.
F   - Intensity in microtesla.
sF  - Standard error of the intensity in microtesla.

Null values are always expressed as ”-999", with exception for the Age data, which are always defined.