Summary

Description

Since the early 1990s the Global Historical Climatology Network-Monthly (GHCN-M) dataset has been an internationally recognized source of data for the study of observed variability and change in land surface temperature. It provides monthly mean temperature data for 7280 stations from 226 countries and territories, ongoing monthly updates of more than 2000 stations to support monitoring of current and evolving climate conditions, and homogeneity adjustments to remove non-climatic influences that can bias the observed temperature record. The release of version 3 monthly mean temperature data in 2011 introduced a number of improvements and changes from the previous release that included consolidating "duplicate" series, updating records from recent decades, and the use of new approaches to homogenization and quality assurance. The next version of GHCN-Monthly is expected to be released in 2015. Version 4 will contain more than 30,000 stations with monthly mean temperature data and improved quality control and bias correction processes.