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Thermal internal boundary layer.

Source: R/boundary_layers.R
bound_thermal_avg.Rd

This function calculates the average height of the thermal internal boundary layer (TIBL). The TIBL height is calculated based on various meteorological parameters such as windspeed, height of the anemometer, type of surface, distance to the point of temperature change, potential temperatures, and lapse rate, following the method described by Bendix (2004, p. 242).

Usage

bound_thermal_avg(
  v,
  z,
  temp_change_dist,
  t_pot_upwind,
  t_pot,
  lapse_rate,
  surface_type = NULL,
  obs_height = NULL
)

Arguments

v

Numeric. The windspeed at the height of the anemometer in meters per second (m/s).

z

Numeric. The height of the anemometer in meters (m).

temp_change_dist

Numeric. The distance to the point of temperature change in meters (m).

t_pot_upwind

Numeric. The potential temperature in the upwind direction in degrees Celsius (°C).

t_pot

Numeric. The potential temperature at the site in degrees Celsius (°C).

lapse_rate

Numeric. The lapse rate in degrees Celsius per meter (°C/m).

surface_type

Character. The type of surface. Options: "field", "acre", "lawn", "street", "agriculture", "settlement", "coniferous forest", "deciduous forest", "mixed forest", "city", "water", "shrub". Either surface_type or obs_height must be provided.

obs_height

Numeric. The observation height for roughness length calculation in meters (m). Either obs_height or surface_type must be provided.

Value

Numeric. The average height of the thermal boundary layer in meters (m).

Details

The thermal internal boundary layer (TIBL) forms as air flows over a surface with a different temperature, causing thermal stratification. This function computes the average height of the TIBL, which is influenced by windspeed, temperature differences, and the atmospheric lapse rate.

The function uses the formula: $$height = \frac{u_*}{v} \sqrt{\frac{d \Delta \theta}{\gamma}}$$ where \(u_*\) is the friction velocity, \(v\) is the windspeed, \(d\) is the distance to the temperature change point, \(\Delta \theta\) is the potential temperature difference, and \(\gamma\) is the lapse rate.

References

Bendix, J. (2004). Weather and Climate: An Introduction. Springer.

Examples

# Calculate the average height of the TIBL with given parameters
bound_thermal_avg(
  v = 5, z = 10, temp_change_dist = 500,
  t_pot_upwind = 15, t_pot = 20,
  lapse_rate = 0.0065, surface_type = "lawn"
)
#> [1] 63.41207