Number of combined summer days (Tmax over 30°C) and tropical nights (Tmax over 20°C) per year (1987-2016 average), Jan. 2019

The dataset presents the average number of combined hot days - with maximum temperature over 30 degrees Celsius - and tropical nights - with minimum temperature over 20 degrees Celsius - in the period 1987-2016, for a series of individual European cities from Eurostat's Urban Audit 2011-2014 spatial dataset. The associated values are based on the E-OBS dataset from the EU-FP6 project ENSEMBLES (http://ensembles-eu.metoffice.com) and around 10,000 meteorological stations across Europe. The combination of hot days and warm nights is particularly dangerous to human health, as the high temperatures during night time does not allow for the cities and buildings to cool down. Such combination, if lasting over several days (heatwaves) can have severe health implications or even be fatal to the elderly, babies or those in poor health. Therefore, the knowledge of the occurrence of such conditions in a given location can be useful in planning adaptation to the changing climate and protection of the vulnerable groups from heat. This dataset has been used also in the EEA Report No 22/2018 "Unequal exposure and unequal impacts: social vulnerability to air pollution, noise and extreme temperatures in Europe" (https://www.eea.europa.eu/publications/unequal-exposure-and-unequal-impacts/at_download/file).