STEAD: a high-resolution daily gridded temperature dataset for Spain

Using 5520 observatories covering the whole territory of Spain (about 1 station per 90 km(2) considering the whole period), a daily gridded maximum and minimum temperature was built covering a period from 1901 to 2014 in peninsular Spain and 1971 to 2014 in the Balearic and Canary Islands. A comprehensive quality control was applied to the original data, and the gaps were filled on each day and location independently. Using the filled data series, a grid of 5 km x 5 km spatial resolution was created by estimating daily temperatures and their corresponding uncertainties at each grid point. Four daily temperature indices were calculated to describe the spatial distribution of absolute maximum and minimum temperature, number of frost days and number of summer days in Spain. The southern plateau showed the maximum values of maximum absolute temperature and summer days, while the minimum absolute temperature and frost days reached their maximums at the northern plateau. The use of all the available information, the complete quality control and the high spatial resolution of the grid allowed for an accurate estimate of temperature that represents a precise spatial and temporal distribution of daily temperatures in Spain.