Some thoughts on the Global Historical Climate Network Daily (GHCN-D) Data
Introduction The GHCN-D data is the primary source data for most land-based climate data bases. The data is accessible at https://www.ncei.noaa.gov/products/land-based-station/global-historical-climatology-network-daily . This data is collected by NOAA. These are very large files, with each year's file approximately 1 gigabyte in size, though the files become smaller as one goes back in time. There are approximately 125,000 stations in the files, though as we shall see, only about a third of those stations have data at any point in time. The data I collected includes three temperature measurements, TMAX, TMIN, and TAVG (the maximum observed temperature, the minimum observed temperature, and the average observed temperature) each measured in 10s of degrees Celsius, two snow measurements SNOW and SNWD (snow fall and snow depth on the ground) each in mm, and PRCP (precipitation) measured in mm. In addition to the observed value for each variable, the data set includes three other va