gmeterpy.corrections.atmosphere¶
Atmospheric pressure correction.
This module contains the atmospheric correction to the gravity observations.
Functions
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Atmospheric pressure correction. |
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Normal atmospheric pressure. |
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atmospheric_pressure_correction(height: Unit("m"), pressure: Unit("Pa"), barometric_factor: Unit("uGal / mbar") = <<class 'astropy.constants.constant.Constant'> name='Default sensitivity of changes in gravity with variations in atmospheric pressure.' value=0.3 uncertainty=0.0 unit='uGal / mbar' reference='IAG 1983 Resolution no.9'>) -> Unit("uGal")[source]¶ Atmospheric pressure correction.
- Parameters
height (Quantity) – Height above sea level.
pressure (Quantity) – Observed atmospheric pressure.
barometric_factor (Quantity) – Barometric factor. Default is 0.3 uGal / mBar as recommended by IAG.
- Returns
delta_g_atm – Atmospheric pressure correction.
- Return type
Quantity
Notes
The lumped effects of direct gravitation of air mass changes and indirect effect via deformation of the solid earth have been determined empirically from air pressure variations. It is recommended to reduce these effects through (IAG 1983 resolution no. 9)
\[\Delta g = 0.30\times 10^{-10} (p_a - p_n)\quad [\textrm{ms}^{-2}]\]where \(p_a\) – actual observed air pressure, \(p_n\) – normal pressure calculated by gmeterpy.corrections.atmosphere.normal_pressure function, 0.3 uGal / mBar – default barometric factor.
The actual value of \(p_n\) needs to be documented.
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normal_pressure(height: Unit("m")) -> Unit("Pa")[source]¶ Normal atmospheric pressure.
- Parameters
height (Quantity) – Height above sea level.
- Returns
pn – Normal pressure.
- Return type
Quantity
Notes
The normal pressure is referred to the DIN5450 (ISO 2533:1975) Standard Atmosphere 1:
\[p_n = 101325 \left(1 - 0.0065 \dfrac{H}{288.15}\right)^{5.2559}\quad [\textrm{Pa}]\]where \(H\) – physical height of the station in metres.
- 1
International Organization for Standardization 1975 Standard Atmosphere ISO 2533 1975