MAPA DE CLASSIFICAÇÃO CLIMÁTICA DE THORNTHWAITE PARA O LESTE MARANHENSE.

Thornthwaite's climate classification is one of the most used in the world, whether for geographic, meteorological, climatological, bioclimatological, ecological studies, among others. This study aimed to generate a detailed Thornthwaite climate classification map for Eastern Maranhão. A total of 101 meteorological observation points were used, from which the variables average air temperature and rainfall were obtained, within the time range from 1950 to 2021. Such data were evaluated and subsequently processed in an Excel and GIS environment. In Excel, climatological water balances were calculated using the Thornthwaite and Mather method, using 100 mm as soil water storage capacity, in addition to determining the indices of the temperature equations by multiple linear regression for subsequent spatialization in matrix images of latitude and longitude. Precipitation and evapotranspiration data were interpolated using ordinary kriging, with a spatial resolution of 90 m, equal to that of the digital elevation model made available by the National Institute for Space Research. More than 8,727,760.0 pixels were evaluated, identifying the dry subhumid C1 and rainy subhumid C2 climate types, described by the subtypesC1 dA’a’,C1 wA’a’,C1w2A’a’ and C2 w2A’a’. Overall, it was identified that 94% of the East Maranhense area is occupied by aC1 climate and 6% by a C2 climate. It is understood that this study generated accurate scientific information to support agricultural and urban planning, water resources management and the development of sustainable environmental policies for Eastern Maranhão. [ABSTRACT FROM AUTHOR]