In the past few decades, many studies showed a significant worldwide warming, and consequently, changes in frequency and persistence of extreme high-temperature events were observed. In order to analyse summer Tuscany (Italy) patterns of climate change during the period 1955–2004, indices of temperature and of extreme events were investigated for evidence of trend and change in inter-annual variability by using data of 40 weather stations. Least square regression analysis and Theil-Sen nonparametric regression were applied for evidence of trends. The Mann–Kendall test was applied to each time series to look for statistically significant trends.
The results showed a general increase in minimum and maximum temperatures and extreme temperature events. Maximum temperature increase (+0.44 °C/decade) was slightly greater than minimum temperature (+0.38 °C/decade) and consequently, an increase in summer daily temperature range (DTR) was noted (+0.06 °C/decade).
Inter-annual summer climate variability showed an increasing trend in the whole region, especially in regard to extreme event occurrences while a small decreasing trend concerning diurnal temperature range was observed. Copyright © 2008 Royal Meteorological Society