w_etp {htsr}

Compute the potential evapotranspiration with several methods

Description

ETP calculation

Usage

w_etp(
  method = c("Turc", "Penman-Monteith", "Priestley-Taylor", "Makkink",
    "Heargraves-Samani"),
  freq = c("day", "month"),
  f_temp,
  f_relh = NA,
  f_radg = NA,
  f_radn = NA,
  f_atmp = NA,
  f_wvel = NA,
  f_tmin = NA,
  f_tmax = NA,
  lat = NA,
  alt = NA,
  albedo = NA,
  z = NA
)

Arguments

method

Method "Turc", "Penman-Monteith", "Priestley-Taylor", "Makkink", "Heargraves-Samani"

freq

Frequency "day", "month"

f_temp

File of air temperature in degC, mandatory

f_relh

File of relative humidity in percent, mandatory

f_radg

File of global radiation in W/m2

f_radn

File of net radiation in W/m2

f_atmp

File of atmospheric pressure in hPa

f_wvel

File of wind velocities in m/s

f_tmin

File of air min temperature in degC

f_tmax

File of air max temperature in degC

lat

Latitude in deg

alt

Altitude in m

albedo

Albedo

z

Anemometer high in m

Details

f_temp and f_relh are mandatory in all cases.

For the Turc method, f_radg is needed.

For the Penman-Monteith method, f_atmp, f_wvel, h and z are needed. If f_radn is not avalaible, lat, f_tmin and ftmax are also needed.

The Turc method only works with a monthly frequence.

Value

An hts files resulting of the operation with a name composed as:

<J or M><EtpTu>_<Station_id>.hts for the Turc method,

<J or M><EtpPM>_<Station_id>.hts for the Penman-Monteith method,

<J or M><EtpPT>_<Station_id>.hts for the Priestley-Taylor method

<J or M><EtpMa>_<Station_id>.hts for the Makkink method

<J or M><EtpHS>_<Station_id>.hts for the Heargraves-Samani method

Author(s)

P. Chevallier - April 2020-Nov2022

Source

Hingray, B., Picouet, C., Musy A., Hydrologie, une science pour l'ingénieur, Presses Plolytechniques et Universitaires Romandes, 2008,

Allen, R.G., L.S. Pereira, D. Raes, and M. Smith. 1998. Crop Evapotranspiration. Guidelines for Computing Crop Water Requirements. FAO Irrigation and Drainage Paper 56. 300p

Er-Raki, S., A. Chehbouni, S. Khabba, V. Simonneaux, L. Jarlan, A. Ouldbba, J. C. Rodriguez, and R. Allen. 2010. “Assessment of Reference Evapotranspiration Methods in Semi-Arid Regions: Can Weather Forecast Data Be Used as Alternate of Ground Meteorological Parameters?” Journal of Arid Environments 74 (12): 1587–96. https://doi.org/10.1016/j.jaridenv.2010.07.002.