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This paper aims to find probabilities of extreme values of the air temperature for the Cerrado, Pantanal and Atlantic Forest biomes in Mato Grosso do Sul in Brazil. In this case a maximum likelihood estimation was employed for the probability distributions fitting the extreme monthly air temperatures for 2007–2018. Using the Extreme Value Theory approach this work estimates three probability distributions: the Generalized Distribution of Extreme Values (GEV), the Gumbel (GUM) and the Log-Normal (LN). The Kolmogorov–Smirnov test, the corrected Akaike criterion AICc, the Bayesian information criterion BIC, the root of the mean square error RMSE and the determination coefficient R2 were applied to measure the goodness-of-fit. The estimated distributions were used to calculate the probabilities of occurrence of maximum monthly air temperatures over 28–32 °C. Temperature predictions were done for the 2-, 5-, 10-, 30-, 50- and 100-year return periods. The GEV and GUM distributions are recommended to be used in the warmer months. In the coldest months, the LN distribution gave a better fit to a series of extreme air temperatures. Deforestation, combustion and extensive fires, and the related aerosol emissions contribute, alongside climate change, to the generation of extreme air temperatures in the studied biomes. [ABSTRACT FROM AUTHOR]

Climate and water contacts are among the most important risk factors of human schistosomiasis transmission. This study aimed to determine-through direct field observations-the influence of air temperature on the frequencies of children´s water contacts with respect to human schistosomiasis transmission risk in the Sourou Valley, located in the North-western part of Burkina Faso. The objectives of the study were: (i) to study the air temperature at which children have the sensation of heat and start looking for water as a means for natural cooling; and (ii) to study whether high frequencies of swimming or bathing may lead to a higher risks of schistosomiasis transmission. To do so, swimming or bathing were observed during two different periods: a cold one from 3rd January to 2nd February 2011 and a hot one from 3rd April to 3rd May 2011 in Toma-Île, a village totally surrounded by water. The results showed that daily mean air temperatures never exceeded 30 °C during the coldest period, while they were above this value during the hottest period. In total, swimming activities were observed 11/31 days during the coldest period and 31/31 during the hottest period. Bathing of children below the age of 5 years occurred on 55/62 days. 25 °C was the day mean air temperature from which children felt hot and began playing in water. The hourly occurrence of swimming and bathing showed peaks at 2 PM. This coincides with the diurnal maximum of infective cercariae present in the same water. Thus, in order to freshen up during hot periods of the day, children used to look for freshwater and thus expose themselves to a high schistosomiasis transmission risk. [ABSTRACT FROM AUTHOR]

Long-term trend and abrupt changes of major climate variables in the Taihu Basin were investigated based on the mean, maximum and minimum air temperature, diurnal temperature range (DTR), precipitation, relative humidity and sunshine duration at six meteorological stations from 1954 to 2006. Results showed that the long-term trend for annual precipitation was not statistically significant during the past 53 years, but a wetter tendency was detected and the increasing centre for annual precipitation was located in the southeast of the study area. Mean air temperature has increased by 1.43°C, similar trends were also identified for maximum and minimum air temperature, which have increased by 1.06 and 1.54°C, respectively, while DTR exhibited a slight decreasing trend with a rate of about −0.09°C/(10 year). The annual mean relative humidity and sunshine duration exhibited a decreasing trend, with Kendall slope values of −0.99%/10 year and −7.797 h/10 year, respectively. Examination of long-range dependence showed that all climate variables exhibited strong persistence at annual scale except minimum air temperature. Detection of abrupt changes using nonparametric Mann-Kendall and Pettitt methods showed different results. Abrupt changes occurred in the 1980s and 2000s for annual precipitation using the nonparametric Mann-Kendall method, while no abrupt changes were detected using the Pettitt method. Abrupt changes of temperature and relative humidity took place in the early 1990s using the nonparametric Mann-Kendall method, which occurred in the late and mid 1980s using the Pettitt method, while abrupt changes of sunshine duration and DTR detected by two methods occurred in the similar period. The result will be helpful for local flood control and drought relief in urban planning and construction under future global climate change. [ABSTRACT FROM AUTHOR]