The function estimates body temperatures (K, operative environmental temperature) of an ectotherm using an approximation based on Campbell and Norman (1998) and Mitchell (1976) .

Tb_CampbellNorman(
  T_a,
  T_g,
  S,
  alpha_S = 0.7,
  alpha_L = 0.96,
  epsilon = 0.96,
  c_p = 29.3,
  D,
  V
)

Arguments

T_a

numeric air temperature (K).

T_g

numeric ground temperature (K).

S

numeric flux density of solar radiation (W m-2), combining direct, diffuse, and reflected radiation accounting for view factors.

alpha_S

numeric organismal solar absorptivity (proportion).

alpha_L

numeric organismal thermal absorptivity (proportion); 0.965 for lizards (Bartlett and Gates 1967) .

epsilon

numeric longwave infrared emissivity of skin (proportion), 0.95 to 1 for most animals (Gates 1980) .

c_p

numeric specific heat of air (J mol-1 K-1).

D

numeric characteristic dimension of the animal (m).

V

numeric wind speed (m s-1).

Value

numeric operative environmental temperature, T_e (K).

Details

Boundary conductance uses a factor of 1.4 to account for increased convection (Mitchell 1976) . The function assumes forced conduction.

References

Bartlett PN, Gates DM (1967). “The energy budget of a lizard on a tree trunk.” Ecology, 48, 316-322.

Campbell GS, Norman JM (1998). Introduction to environmental biophysics, 2nd ed. edition. Springer, New York. ISBN 0387949372.

Gates DM (1980). Biophysical Ecology. Springer-Verlag, New York, NY, USA.

Mitchell JW (1976). “Heat transfer from spheres and other animal forms.” Biophysical Journal, 16(6), 561-569. ISSN 0006-3495, doi:10.1016/S0006-3495(76)85711-6 , https://www.sciencedirect.com/science/article/pii/S0006349576857116.

Examples

Tb_CampbellNorman (T_a     = 303, 
                   T_g     = 303, 
                   S       = 823, 
                   alpha_S = 0.7, 
                   alpha_L = 0.96, 
                   epsilon = 0.96, 
                   c_p     = 29.3, 
                   D       = 0.17, 
                   V       = 1)
#> [1] 332.5574