A cross-checked global monthly weather station database for precipitation covering the period 1901 to 2010

This database entry represents a comprehensive compilation of monthly weather station records for precipitation from multiple data sources for the period 1901-2010, with an emphasis on climate normal averages for the period 1961-1990. The database corresponds to the journal publication: Castellanos-Acuña, D. and Hamann, A. 2020. A cross-checked global monthly weather station database for precipitation covering the period 1901 to 2010. Geoscience Data Journal (https://rmets.onlinelibrary.wiley.com/journal/20496060, article in press, January 2020).

We use digital elevation models and nearby stations to search for inconsistencies in reported station locations and recorded precipitation values. We also estimated missing values in weather station time series using a linear model approach based on interpolated anomaly surfaces. The resulting station records were ranked into ten classes, according to the completeness of records, the reliability of missing value estimations and other criteria. We corrected incomplete or erroneous location and elevation information for 12% of all available station records. A total of 23% of monthly records that had missing values could be estimated with high or moderate confidence. We sub-sampled our global database of more than 80,000 stations with various spatial filters, so that only the highest quality station for a given area was retained.

Our contribution significantly enhances global data coverage compared to individual databases currently available. Even when accepting only the stations within the top two quality ranks in our combined database, and applying the coarsest spatial filter of one station per approximately 1,600 km², the remaining station count of more than 20,000 stations exceeds the largest alternative database (without a spatial filter applied) by more than 50%.

The database contains a "Station Statistics" file with various flags indicating station quality and completeness of records. Monthly precipitation data is provided as one large file, but also broken down into regional files with less than one million rows each. Climate normal estimates for the 1961-1990 period, useful as a baseline prior to significant anthropogenic warming, are provided in multiple files with global coverage, but with different spatial filters applied that select the highest quality stations based for a global grid at different resolutions.