| (1) | H_N = \sqrt{\frac{a_e \, A_T }{\pi}} \, \ln \frac{\delta T_A }{\delta T_{\rm cut} } |
where
H_N | true vertical of the Neutral Temperature Layer below the Earth's surface |
a_e | Local average Thermal diffusivity of the soil between Earth's surface and neutral layer |
A_T | Period of annual temperature variation cycle: A_T = 1 \, {\rm year} |
\delta T_A | Annual average surface temperature variation based on weather reports |
\delta T_{\rm cut} | Temperature measurement threshold (usually \delta T_{\rm cut} = 0.001 \, {\rm °C}) |
See Also
Geology / Neutral Temperature Layer
[ Geothermal Temperature Field ] [ Geothermal Temperature Profile ]