komanawa.basgra_nz_py.supporting_functions.conversions#

Author: Matt Hanson Created: 23/10/2020 10:06 AM

Functions#

convert_RH_vpa(rh, tmin, tmax)

calculate vapour pressure from rh tmin/tmax assumes tmean is tmin+tmax/2 as per https://www.weather.gov/media/epz/wxcalc/vaporPressure.pdf

convert_wind_to_2m(ws, z)

Convert wind speed measured at different heights above the soil surface to wind speed at 2 m above the surface, assuming a short grass surface. Based on FAO equation 47 in Allen et al (1998).

Module Contents#

convert_RH_vpa(rh, tmin, tmax)[source]#

calculate vapour pressure from rh tmin/tmax assumes tmean is tmin+tmax/2 as per https://www.weather.gov/media/epz/wxcalc/vaporPressure.pdf

Parameters:
  • rh – relative humidity (%, 0-100)

  • tmin – min temperature (degrees c)

  • tmax – max temperature (degrees c)

Returns:

vapour pressure (kpa)

convert_wind_to_2m(ws, z)[source]#

Convert wind speed measured at different heights above the soil surface to wind speed at 2 m above the surface, assuming a short grass surface. Based on FAO equation 47 in Allen et al (1998).

Parameters:
  • ws – Measured wind speed [m s-1]

  • z – Height of wind measurement above ground surface [m]

Returns:

Wind speed at 2 m above the surface [m s-1]