Berkeley Earth Surface Temperature has created a preliminary merged dataset, combining 1.6 billion temperature reports from 16 pre-existing data files. Whenever possible, we used raw data rather than previously homogenized or edited data. After eliminating duplicate records, the current file contains over 39,000 unique stations. This is approximately five times the 7,280 stations found in the Global Historical Climatology Network (GHCN-M) monthly dataset that has served as the focus for many climate studies. The GHCN-M is limited by strict requirements for length, integrity, and the need for nearly complete reference periods used to define baselines. We developed new algorithms that reduce the need to impose these requirements (see methodology), and as such, we intentionally created a more comprehensive dataset. We performed a series of tests to identify dubious data and merge identical data from various files. In general, our process was to flag dubious data rather than simply eliminating it. Flagged values were generally excluded from subsequent analyses, but their content is preserved for future consideration.