| \(A\) |
surface or cross-sectional area (\(m^2\)) |
|
| \(a\) |
altitude angle of the sun (degrees) (subscripts: s, for normal to a slope; c ,for the axis of a cylinder); albedo (subscript: s, surface) |
|
| \(Acondfact\) |
proportion of the animal surface area that is in contact with the ground |
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| \(Agradfact\) |
proportion of the animal projected area exposed to radiation from the ground |
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| \(abs\) |
absorptivity to solar radiation (proportion) |
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| \(air_{pressure}\) |
air pressure (kPa) |
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| \(aran\) |
scale performance value for performance curve? if aran = 0, no scaling; if aran = 1, includes a thermodynamic effect on mean performance |
|
| \(breadth\) |
breadth of the thermal performance curve |
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| \(c\) |
specific heat capacity (subscripts: \(a\), air; \(p\), air at constant pressure; \(so\), soil) (\(J kg^{-1}K^{-1}\) or \(J kg^{-1}{°C}^{-1}\)) |
|
| \(CT\) |
critical thermal limit (\(°C\)) (subscripts: min, minima; max, maxima), the lower and upper temperature limit for performance |
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| \(D\) |
characteristic dimension (\(m\)); thoracic diameter (\(cm\)) |
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| \(d\) |
thickness of material (\(m\)); diameter of a cylinder (\(m\)) |
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| \(day\) or \(doy\) |
day of year |
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| \(deg\) |
angle (degrees) |
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| \(depth\) |
depth (\(cm\)) |
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| \(e\) |
water vapor pressure (\(N m^{-2}, mbar\)) (subscripts: \(a\), of the air; \(s\), at saturation) |
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| \(ef\) |
enhancement factor, used to adjust convective heat transfer coefficient to field conditions |
|
| \(elev\) |
elevation above mean sea level (\(m\)). |
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| \(F\) |
view factor between the animal and radiation stream (dimensionless) (subscripts: \(a\), atmospheric radiation; \(d\), diffuse solar radiation; \(g\), ground thermal radiation; \(r\), reflected solar radiation) |
|
| \(g_{a}\) |
a shape factor for soil particles |
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| \(H\) |
solar radiation (\(W m^{-2}\)) (subscripts: \(sdir\), for direct flux; \(sdif\), for diffuse flux; \(sref\), for reflected flux) |
|
| \(H_L\) or \(H\) |
convective heat transfer coefficient (\(W m^{-2}{°C}^{-1}\) or \(W m^{-2}K^{-1}\)) |
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| \(Hr\) |
mean month relative humidity (percentage) |
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| \(h\) |
height (\(m\)); length of a cylinder (\(m\)); relative humidity (decimal fraction); Planck’s constant (\(J s\)); hour angle (rad) |
|
| \(hour\) |
hour (0-24) |
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| \(K\) |
thermal conductance (\(W m^{-2}{°C}^{-1}\)) (subscripts f, fur; g, substrate; s, skin; sf, skin and fur; o, overall heat conductance for an animal; c, surface boundary layer for convection; so, soil). |
|
| \(k\) |
von Karman’s constant (dimensionless), k~0.41 |
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| \(k_{so}\) |
soil thermal conductivity (\(W m^{-1}K^{-1}\)) |
|
| \(K_t\) or \(kt\) |
clearness index, the ratio of the global solar radiation measured at the surface to the total solar radiation at the top of the atmosphere (dimensionless) |
|
| \(L\) |
Monin-Obukhov length (\(m\)), a measure of the instability of heat flow |
|
| \(l\) or \(L\) |
length (\(m\)) |
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| \(lon\) |
longitude (degrees) |
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| \(lat\) |
latitude (degrees) |
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| \(LDT\) |
lower developmental threshold (\(°C\)) |
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| \(lw\) |
downward flux of near-infrared radiation (\(Wm^{-2}\)) |
|
| \(m\) |
mass (\(kg\) or \(g\)); air mass (dimensionless) |
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| \(P\) |
monthly precipitation (\(mm\)) |
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| \(psa\) |
proportion surface exposed (dimensionless) (subscripts: \(air\), for exposure to air; \(ref\), for exposure to ground; \(dir\), for exposure to sky or enclosure; \(g\), for exposure to substrate) |
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| \(Q_{abs}\) |
solar and thermal radiation absorbed (\(W\)) |
|
| \(Q_{emit}\) |
thermal radiation emitted (\(W\)) |
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| \(Q_{conv}\) |
energy exchange between an animal and the surrounding substance due to convection (\(W\)) |
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| \(Q_{cond}\) |
energy exchange between an animal and the surface due to conduction (\(W\)) |
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| \(Q_{met}\) |
energy emitted due to metabolism (\(W\)) |
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| \(Q_{evap}\) |
energy emitted due to evaporative water loss (\(W\)) |
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| \(r\) |
reflectance (decimal fraction) (subscripts: \(g\), of ground; \(S\), to direct sunlight; \(s\), to skylight); diffusion resistance to water vapor (\(s m^{-1}\)) (subscripts: \(b\), boundary layer; \(i\), internal or intercellular); resistance to heat flow (\(s m^{-1}\)) (subscripts: \(h\), \(ha\), boundary layer; \(j\), diffusion resistance to molecular species j; radius (\(m\)) (subscripts: \(b\), of inside body wall of animal; \(r\), of outer surface of animal) |
|
| \(rad\) |
angle (radians) |
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| \(raz\) |
solar azimuth angle (degrees) |
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| \(S\) |
amount of sunlight incident upon the earth’s surface (\(W m^{-2}\)) (subscripts: \(dir\), direct solar radiation; \(dif\), diffuse solar radiation; \(h\), on a horizontal surface; \(ref\), reflected solar radiation) |
|
| \(shade\) |
whether soil temperature is calculated in the shade or not |
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| \(shift\) |
mode of the thermal performance curve |
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| \(skew\) |
skewness of the thermal performance curve |
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| \(sol.elev\) |
solar elevation angles (degrees) |
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| \(solrad\) |
solar radiation (\(W m^{-2}\) per day) |
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| \(SSA\) |
solar absorptivity of soil surface (proportion) |
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| \(svl\) |
lizard snout vent length (\(mm\)) |
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| \(t\) |
time (\(hr\) or \(s\)) (subscripts: \(as\), after sunset; \(n\), time of minimum temperature; \(r\), sunrise; \(s\), sunset; \(p\), rise the following day; \(x\), time of maximum temperature) |
|
| \(T\) |
temperature (\(°C\) or \(K\) or \(°F\)) (subscripts: \(a\), air; \(g\), ground; \(s\), surface; \(sh\), shade; \(sky\), effective radiant temperature of the sky) |
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| \(T_{dewpoint}\) |
dewpoint temperature (\(°C\)) |
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| \(T_{e}\) |
Operative environmental temperature (\(°C\)) |
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| \(T_{max}\) |
maximum temperature of the day (\(°C\)) |
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| \(T_{min}\) |
minimum temperature of the day (\(°C\)) |
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| \(Tg_{max}\) |
maximum soil surface temperature of the day (\(°C\)) |
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| \(Tg_{min}\) |
minimum soil surface temperature of the day (\(°C\)) |
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| \(T_{opt}\) |
thermal optima, the temperature at which peak performance occurs (\(°C\)) |
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| \(T_{soil0}\) |
initial soil temperature (\(°C\)) |
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| \(tolerance\) |
maximal breath (\(°C\)) of the thermal performance curve |
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| \(u\) |
wind speed (\(m s^{-1}\)) (subscripts: \(r\), reference height or heights) |
|
| \(UDT\) |
upper developmental threshold (\(°C\)) |
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| \(V\) |
velocity (\(m s^{-1}\)); volume (\(m^{3}\)) |
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| \(water_{content}\) |
water content (percent) |
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| \(x\) |
vector of volume fractions of soil constituents (e.g., clay, quartz, minerals other than quartz, organic matter, water, air) |
|
| \(z\) |
distance, or height above a surface (\(m\)); zenith angle (°) |
|
| \(zr\) |
reference height (\(m\)) |
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| \(z0\) |
roughness height (\(m\)) |
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