oce (version 0.1-82)

apply.magnetic.declination: Earth magnetic declination

Description

Earth apply.magnetic declination

Usage

apply.magnetic.declination(x, declination=0, debug=getOption("oce.debug"))

Arguments

x

an oce object.

declination

magnetic declination (to be added to the heading)

debug

a debugging flag, set to a positive value to get debugging.

Value

• Object, with velocity components ajusted to be aligned with geographic north and east.

concept

tide

Details

Instruments that use magnetic compasses to determine current direction need to have corrections applied for magnetic declination, to get currents with the y component oriented to geographic, not magnetic, north. Sometimes, and for some instruments, the declination is specified when the instrument is set up, so that the velocities as recorded are already. Other times, the data need to be adjusted. This function is for the latter case.

References

http://www.ngdc.noaa.gov/IAGA/vmod/igrf.html

See Also

Use magnetic.declination to determine the declination at a given spot on the world, at a given time.

Examples

library(oce)