Monthly reference evapotranpiration for the State of Piaui, Brazil

Revista Brasileira de Engenharia Agrícola e Ambiental

Andrade Júnior, Aderson S. de³  Gomes, Adriano A. N.¹  Medeiros, Raimundo M. de² 

[1] UFCG, Teresina;Secretaria Estadual de Meio Ambiente e dos Recursos Naturais, Teresina;Embrapa Meio Norte, Teresina

关键词: agricultural planning;    irrigation;    water demand;    water balance    INTRODUÇÃO A agricultura é uma atividade econômica que por estar sujeita à variabilidade do clima;    do mercado e da política agrária;    torna-se instável e de alto risco;    devendo ser bem planejada para garantir o seu sucesso;   

DOI  :  10.1590/S1415-43662005000400019

学科分类：农业科学（综合）

来源: Universidade Federal de Campina Grande * Centro de Ciencias e Tecnologia

【 摘 要 】

The objective of this work was to estimate the mean monthly reference evapotranspiration (ETo) for Piaui State, Brazil. The ETo estimates were performed by the Thornthwaite's (1948) empirical method, based on estimated mean air temperature equations developed by Lima & Ribeiro (1998). The ETo was estimated for 222 municipalites of Piaui State. The values were arranged in a spatial distribution and grouped in classes with 25 mm interval. Maps of monthly ETo were prepared. The monthly ETo values ranged from 55.4 to 212.0 mm, showing large evapotranspiration variation among the several regions of Piaui State. Lower monthly ETo values were obtained for the period of February to July, while the higher values were observed for September to December. The spatial distribution of the monthly ETo values occurred as a function of the spatial variation of the monthly mean air temperature in the different regions of Piaui State.

【 授权许可】

CC BY-NC