The Climate.gov web site has a good introductory section on climate data.  You can find the primer at https://www.climate.gov/maps-data/primer/climate-data-primer.  It includes information on how climate is measured, how the data are processed and quality controlled, how past climates are interpreted and how future climate is predicted, and where to get climate data.  I also have a slide set on “Sources of Weather and Climate Data” that I would be happy to send you if you email me (pknox “at” uga.edu).  And you can also contact me if you need any help determining what data you need  and where to get it.

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