Steve Wilkinson's Sandbox
Soil and air temperature relationship
I found some posted notes by a faculty member in the Technishe Universitat Braunschweig (although the format of the notes has a UConn logo) explicitly on soil temperature. Using the heat equation he develops the same formula in Chang, Mingteh; Crowley, Christopher M.; Juin, Eric; Watterston, Kenneth G., 1994: "Air and soil temperatures under three forest conditions in east Tex." However, the parameters in the model have solid meaning that we can adapt for our purposes. The link to the notes is http://www.pci.tu-bs.de/agbauerecker/VorlesungSolarthermieUndWaermepumpen2014/WaermeeintragErdeLecture17_Spring2004.pdf
- "Soil temperature is a factor of primary importance for many physical, chemical, and biological processes. It governs:
- Evaporation and soil aeration
- All kind of chemical processes and reactions within the soil
- Biological processes such as seed germination, seedling emergence and growth, root development, microbial activity
- There are three fundamental characteristics related to diurnal and annual soil thermal regimes.
- We observe diurnal and annual temperature cycles in response to the fluctuating (cyclic) inputs of solar radiation.
- The incoming solar radiation energy is utilized to heat as it travels down the soil profile. That means the available energy decreases with depth. Thus we observe the phenomenon of amplitude damping, or a reduction in the magnitude of these temperature cycles with increasing depth.
- Because it takes time for heat to travel into and out of the soil, there is a delay in the time at which any specific location on the temperature cycle reaches a given point in the soil, and this time lag becomes more pronounced with increasing distance.