United States Historical Climatology Network (USHCN) Version 1

The U.S. Historical Climatology Network is a high-quality moderate sized data set of monthly averaged maximum, minimum, and mean temperature and total monthly precipitation developed to assist in the detection of regional climate change. The USHCN is comprised of 1221 high-quality stations from the U.S. Cooperative Observing Network within the 48 contiguous United States. An additional data set containing 46 stations for Alaska is also available; however, data for these stations are not adjusted for inhomogeneities as outlined below for the USHCN. The period of record varies for each station but generally includes the period 1900-1995. The stations were chosen using a number of criteria including length of period of record, percent missing data, number of station moves and other station changes that may affect the data homogeneity, and spatial coverage. Included with the data set are metadata files that contain station history information about station moves, instrumentation, observing times, and elevation.