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Group canopy_wind

Modules > canopy_wind

Wind speed profile calculations within and above canopy.

Public Functions

Type Name
subroutine canopy_wind_mod::canopy_wind_most (HCM HCM, ZK ZK, FAFRACK FAFRACK, UBZREF UBZREF, Z0GHC Z0GHC, CDRAG CDRAG, PAI PAI, HREF HREF, D_H D_H, ZO_H ZO_H, LAMBDARS LAMBDARS, CANBOT_OUT CANBOT_OUT, CANTOP_OUT CANTOP_OUT, CANWIND CANWIND)
Calculate canopy wind speed profile using MOST.

Public Functions Documentation

function canopy_wind_most

Calculate canopy wind speed profile using MOST. 

subroutine canopy_wind_mod::canopy_wind_most (
    HCM HCM,
    ZK ZK,
    FAFRACK FAFRACK,
    UBZREF UBZREF,
    Z0GHC Z0GHC,
    CDRAG CDRAG,
    PAI PAI,
    HREF HREF,
    D_H D_H,
    ZO_H ZO_H,
    LAMBDARS LAMBDARS,
    CANBOT_OUT CANBOT_OUT,
    CANTOP_OUT CANTOP_OUT,
    CANWIND CANWIND
)

Computes mean wind speed for given height (z) below the canopy top using Monin-Obukhov Similarity Theory above canopy and Massman et al. (2017) parameterization within canopy

Parameters:

  • HCM Height of canopy top (m)
  • ZK Above/Below canopy height, z (m)
  • FAFRACK Fractional (z) shapes of the plant surface distribution (dimensionless)
  • UBZREF Mean wind speed at reference height (ZREF) (m/s)
  • Z0GHC Ratio of ground roughness length to canopy top height (dimensionless)
  • CDRAG Drag coefficient (dimensionless)
  • PAI Total plant/foliage area index (dimensionless)
  • HREF Reference Height above the canopy (ZREF = HCM + HREF; m)
  • D_H Zero plane displacement heights (dimensionless)
  • ZO_H Surface (soil+veg) roughness lengths (dimensionless)
  • LAMBDARS Value representing influence of roughness sublayer (dimensionless)
  • CANBOT_OUT Canopy bottom wind reduction factor = canbot (dimensionless)
  • CANTOP_OUT Canopy top wind reduction factor = cantop (dimensionless)
  • CANWIND Mean canopy wind speed at current z (m/s)

Author:

P. C. Campbell

Date:

Jun 2022

Note:

Based on Massman et al. (2017) algorithms below the canopy and use of MOST above canopy Massman, W.J., J.M. Forthofer, M.A. Finney (2017). An improved canopy wind model for predicting wind adjustment factors and wildland fire behavior. Canadian Journal of Forest Research, 47(5), 594-599. https://doi.org/10.1139/cjfr-2016-0354