I have climatic-related data of weather stations and intend to generate maps for these data using spatial interpolations. The data include growing degree days (GDD), frost-free period (FFP) and occurence of low winter temperature. I have noticed that researches on spatial climatic mapping have done for precipitation and minimum, maximum temperature by regression, geostatistics and other methods, but not for climatic variables derived from precipitation and temperature (like GDD and FFP, both were calculated from daily temperature data). Does anyone know references that apply spatial interpolations directly to these derived climatic variables? Will that be valid to do so? Or do I have to map the temperature data (ex.monthly mean or minimum temperature) first and use the modelled temperature to generate the GDD and FFP maps that I want?
Any suggestions are appreciated. Thank you very much.
[Non-text portions of this message have been removed]