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  2. Physical properties of soil - Wikipedia

    en.wikipedia.org/wiki/Physical_properties_of_soil

    Whiter soil tends to have a higher albedo than blacker soil cover, which encourages whiter soils to have lower soil temperatures. [85] The specific heat of soil is the energy required to raise the temperature of soil by 1 °C. The specific heat of soil increases as water content increases, since the heat capacity of water is greater than that ...

  3. Soil thermal properties - Wikipedia

    en.wikipedia.org/wiki/Soil_thermal_properties

    One possible way of assessing soil thermal properties is the analysis of soil temperature variations versus depth Fourier's law, Q = − λ d T / d z {\displaystyle Q=-\lambda dT/dz\,} where Q is heat flux or rate of heat transfer per unit area J·m −2 ∙s −1 or W·m −2 , λ is thermal conductivity W·m −1 ∙K −1 ; dT / dz is the ...

  4. Geothermal gradient - Wikipedia

    en.wikipedia.org/wiki/Geothermal_gradient

    Geothermal gradient is the rate of change in temperature with respect to increasing depth in Earth 's interior. As a general rule, the crust temperature rises with depth due to the heat flow from the much hotter mantle; away from tectonic plate boundaries, temperature rises in about 25–30 °C/km (72–87 °F/mi) of depth near the surface in ...

  5. Permafrost - Wikipedia

    en.wikipedia.org/wiki/Permafrost

    Permafrost temperature profile. Permafrost occupies the middle zone, with the active layer above it, while geothermal activity keeps the lowest layer above freezing. The vertical 0 °C or 32 °F line denotes the average annual temperature that is crucial for the upper and lower limit of the permafrost zone, while the red lines represent seasonal temperature changes and seasonal temperature ...

  6. USDA soil taxonomy - Wikipedia

    en.wikipedia.org/wiki/USDA_soil_taxonomy

    The cryic temperature regime distinguishes some higher-level groups. These regimes are based on the mean annual soil temperature (MAST), mean summer temperature, and the difference between mean summer and winter temperatures all at a soil depth of 50 cm. It is normally assumed that the MAST (in °C) equals the sum of the mean annual air ...

  7. Permeability of soils - Wikipedia

    en.wikipedia.org/wiki/Permeability_of_soils

    For a given soil, the greater the void ratio, the higher the value of the coefficient of permeability. Here 'e' is the void ratio. Based on other concepts it has been established that the permeability of a soil varies as e2 or e3 / (1+e). Whatever may be the exact relationship, all soils have e versus log k plot as a straight line.

  8. Soil formation - Wikipedia

    en.wikipedia.org/wiki/Soil_formation

    It takes decades [116] to several thousand years for a soil to develop a profile, [117] although the notion of soil development has been criticized, soil being in a constant state-of-change under the influence of fluctuating soil-forming factors. [118] That time period depends strongly on climate, parent material, relief, and biotic activity.

  9. Earth's crust - Wikipedia

    en.wikipedia.org/wiki/Earth's_crust

    The temperature of the crust increases with depth, [2] reaching values typically in the range from about 100 °C (212 °F) to 600 °C (1,112 °F) at the boundary with the underlying mantle. The temperature increases by as much as 30 °C (54 °F) for every kilometer locally in the upper part of the crust.