As NOAA's primary station data set, the Global Historical Climatology Network (GHCN) is an integrated database of daily climate summaries from land surface stations across the globe, including a common suite of quality assurance reviews. NOAA’s National Centers for Environmental Information (NCEI) produces the GHCN data set.
GHCN contains records from over 100,000 stations in 180 countries and territories. NCEI provides numerous daily variables, including maximum and minimum temperature, total daily precipitation, snowfall, and snow depth; however, about one half of the stations report precipitation only. Both the record length and period of record vary by station and cover intervals ranging from less than a year to more than 175 years.
Every day there are updates to GHCN-Daily station data from a variety of data streams, which also undergo a suite of quality checks. In addition the dataset is reconstructed each weekend from its 25-plus data source components to ensure that GHCN-Daily is generally in sync with its growing list of constituent sources. During this process, the system applies quality assurance checks to the full dataset.