Subroutine UM513 - set the DGRF/IGRF model coefficients
CALL UM513 (tm, lbl)
Epoch of the geomagnetic field calculation expressed in year [in]
Label of the geomagnetic field model [out]
The subroutine UM513 initializes the expansion coefficients of
the geomagnetic field inside the common block UC140
with the coefficients of the DGRF/IGRF model.
tm arguments specifies the epoch to which the model
has to be extrapolated. The base epochs of the model are the year
multiple of 5 between 1945 and 1995. The expansion coefficients are
extrapolated from the nearst base epoch that precedes the
As result, the
lbl argument contains a string with the
name of the model.
In version 1.11 and earlier, the description of the IGRF/DGRF 45-95
geomagnetic field models were included in a specific block data
Since some Fortran compilers (e.g. Microsoft PowerStation) are not
able to link correctly such block data, the DATA statements have been
included in the subroutine UM533.
Note that the common block
DGRF is not more present in the UNILIB library.
magnetic field description
select a geomagnetic field model
perform a Schmidt normalisation
set the Jensen & Cain 1960 model coefficients
set the GSFC 12/66 model coefficients