absolute_humidity_factor#

hydrometlib.cosmos.absolute_humidity_factor(q, ref_q0)[source]#

Calculate absolute humidity correction factor to neutron counts [unitless]

\[f_Q = 1 + 0.0054 \, (Q - Q_0)\]

where \(Q\) is the absolute humidity and \(Q_0\) (ref_q0) the reference condition; 0.0054 is the empirical structure constant.

References

  • Rosolem, R., W. J. Shuttleworth, M. Zreda, T. E. Franz, X. Zeng, and S. A. Kurc, 2013: The Effect of Atmospheric Water Vapor on Neutron Count in the Cosmic-Ray Soil Moisture Observing System. J. Hydrometeor., 14, 1659-1671, https://doi.org/10.1175/JHM-D-12-0120.1

  • M. Andreasen, K.H. Jensen, D. Desilets, T.E. Franz, M. Zreda, H.R. Bogena, and M.C. Looms. 2017: Status and perspectives on the cosmic-ray neutron method for soil moisture estimation and other environmental science applications. Vadose Zone J. 16(8). https://doi.org/10.2136/vzj2017.04.0086

  • Bogena et al. (2022): https://doi.org/10.5194/essd-14-1125-2022

Empirical structure constant = 0.0054

Parameters:

  • q (Expr) – Absolute humidity [g m-3] (grams per cubic meter)

  • ref_q0 (Expr) – Site attribute - reference condition of absolute humidity [g m-3]

Return type:

Expr

Returns:

Expression or Series for absolute humidity factor [unitless]