Climatological aspects of the increase of the skin cancer (melanoma) incidence rate in Europe

Ultraviolet radiation (UVR) has a detrimental impact on human health. Overexposures can lead to erythema and DNA damage causing various skin cancers, including the most dangerous melanoma. Recently, a large increase in melanoma incidents has been detected in Europe. We search for a link between the increase of the skin cancer incidence rate and early spring (April) trends in surface UVR and meteorological parameters (temperature, cloudiness, and precipitation) for several European sites: Belsk (Poland), Oslo (Norway), Reading (UK), and Uccle (Belgium). The trends are calculated for the periods of 1980-2004 and 2005-2018 using ground-based UV measurements and the reconstructed data by a multilinear regression model. The April trends are of special interest because after winter the human skin is not adapted to high UVR intensity and thus susceptible to solar exposure. Statistically insignificant UV trends are found for all stations except for Belsk with the trend of 5% per 10 years in the former period. Positive trends of 0.5-1.0 degrees C per 10 years (statistically significant) were calculated for all stations in the mean daily maximum temperature of April in the period 1980-2018. In April, total ozone values are negatively correlated with the daily maxima of the surface temperature, so if the temperature is higher than 15 degrees C, the corresponding total ozone values will go below the long-term mean, causing more intense surface UVR. Moreover, high temperatures in April may encourage people to stay longer in the sun and expose parts of the body previously covered by winter clothing, which may result in numerous sunburns yielding a higher risk of melanoma. Thus, social campaigns promoting healthy scenarios of outdoor activities should start earlier than before, that is, at the beginning of spring not just before the summer vacation.