calculate_tidal_offset

  • Calculates the spherical harmonic offset to change tide systems

Calling Sequence

from geoid_toolkit.calculate_tidal_offset import calculate_tidal_offset
delta = calculate_tidal_offset(TIDE, GM, R, refell)

Source code

geoid_toolkit.calculate_tidal_offset(TIDE, GM, R, refell, LOVE=0.3, REFERENCE='tide_free')[source]

Calculates the spherical harmonic offset to change permanent tide systems [4, 6]

Parameters:
TIDE: str

Output permanent tidal system

  • 'tide_free': no permanent direct and indirect tidal potentials

  • 'mean_tide': permanent tidal potentials (direct and indirect)

  • 'zero_tide': permanent direct tidal potential removed

R: float

Average radius used in gravity model

GM: float

Geocentric gravitational constant used in gravity model

refell: str

Reference ellipsoid name

  • 'CLK66': Clarke 1866

  • 'GRS67': Geodetic Reference System 1967

  • 'GRS80': Geodetic Reference System 1980

  • 'HGH80': Hughes 1980 Ellipsoid

  • 'WGS72': World Geodetic System 1972

  • 'WGS84': World Geodetic System 1984

  • 'ATS77': Quasi-earth centred ellipsoid for ATS77

  • 'NAD27': North American Datum 1927

  • 'NAD83': North American Datum 1983

  • 'INTER': International

  • 'KRASS': Krassovsky (USSR)

  • 'MAIRY': Modified Airy (Ireland 1965/1975)

  • 'TOPEX': TOPEX/POSEIDON ellipsoid

  • 'EGM96': EGM 1996 gravity model

LOVE: float, default 0.3

Load love number for degree 2

REFERENCE: str, default ‘tide_free’

Original permanent tidal system of gravity modeld

  • 'tide_free': no permanent direct and indirect tidal potentials

  • 'mean_tide': permanent tidal potentials (direct and indirect)

  • 'zero_tide': permanent direct tidal potential removed

Returns:
delta: float

Offset for changing to tide system