1.1 Climate Climate is the average atmospheric condition of a particular place or region, ranging from months to millions of years, being 30 years the classical period defined by the World Meteorological Organization (WMO). It's represents different weather conditions prevailing at a site or region, considering the analysis of a large amount of data, affecting the majority of human activities, mainly in agriculture. Several researchers have defined the climate word, such as: Koppen (1936) – “the sum of the atmospheric conditions that make a place the earth's surface more or less habitable for humans, animals and plants”; Trewartha (1937) “the mean or normal condition over a long period, such as 20, 30 and 100 years”; Blair (1942) “the summation of weather conditions in historical time” or “climate is the summary of all the manifold weather influences”; Thornthwaite (1948) – “the interaction of meteorological factors that contribute to give the place its character and individuality”; Miller (1959) -"the science that discusses the weather condition of the earth surface”; Oliver (1981) “climate is the aggregate of weather at a given area for a given time period”; and Anwar (1993) "the generalized picture of weather is called climate”.