This study aimed to compare the applicability of three methods of filling gaps in rainfall and temperature data from thirteen automatic weather stations (AWS) in the state of Pernambuco, from January to December 2019. The methods used were arithmetic mean, regional weighting, and simple linear regression. The data estimated by filling techniques have been subjected to comparison using R² and descriptive statistical analysis. The estimated data of air temperature presented R2 equal or very close to 1 for the three methods. On the other hand, the estimated data of rainfall showed values similar or closer to the real data only to regional weighting (R² = 1) and linear regression (R² = 0.99) methods. The smallest values ​​of standard deviation (1.70) for temperature were obtained with linear regression. The regional weighting method and unfilled data showed greater uniformity for precipitation. The analyzed methods to estimate the climatic variables, air temperature, and precipitation, on a monthly scale, were efficient to fill in missing data in the evaluated AWS. The simple linear regression method is more efficient and adequate, followed by regional weighting, to fill in missing data in climate databases.

AVALIAÇÃO DE DESEMPENHO DO MICROASPERSOR EM LINHA LATERAL E SIMULAÇÃO MATEMÁTICA DE SEU GRADIENTE DE ENERGIA     MADSON RAFAEL BARBALHO DA SILVA1; LÍVIA MARIA CAVALCANTE SILVA1; ANA CLÁUDIA DAVINO DOS SANTOS1; FABIANO SIMPLICIO BEZERRA1; CAIO SÉRGIO PEREIRA DE ARAÚJO1 E MANASSÉS MESQUITA DA SILVA1   1 Departamento de Engenharia Agrícola, Universidade Federal Rural de Pernambuco, Dom Manuel de Medeiros, s/n, Dois Irmãos, 52171-900, Recife, Pernambuco, Brasil. E-mail:madsonbarbalhoagronomo@gmail.com; cavalcants.livia@gmail.com; aclaudiadavino@gmail.com; fabianoagro14@gmail.com; caiosergio.ufersa@gmail.com; manasses.ufrpe@gmail.com.     1 RESUMO   Objetivou-se avaliar o desempenho do microaspersor Agropolo modelo MC20 em diferentes condições hidráulicas, gerando informações para um melhor dimensionamento de sistemas de microirrigação e manejo da água em áreas irrigadas. A condução do projeto hidráulico para simulação do gradiente de energia em linhas laterais, considerou-se informações determinadas através da escolha de componentes do projeto. Foram extraídos do catálogo comercial do fabricante os pares de valores referentes a vazão e a pressão e, a partir destes, gerou-se a curva vazão-pressão, onde a simulação foi feita pelo Método Algébrico - Christiansen (MA) e Método Iterativo (SBS) – Back-Step. Para ambos métodos o microaspersor se comportou de maneira semelhante, quando submetido a condições sugeridas pelo fabricante, num espaçamento entre emissores de 5,2 m, usando tubos de polietilenos de diâmetro interno de 13 mm e uma pressão de serviço de 20 mca, admitindo uma variação de 10% da pressão. Foram calculados os coeficientes de uniformidade de pressão (CUp) e de vazão (CUq), ambos com valores superiores à 95%, demonstrando a excelência no desempenho do emissor.   Palavras-chave: hidráulica, modelagem matemática, coeficiente de descarga.     SILVA, M. R. B.; SILVA, L. M. C.; SANTOS, A. C. D.; BEZERRA, F. S.; ARAUJO, C. S. P.; SILVA, M. M. PERFORMANCE EVALUATION OF THE SIDE LINE MICROSPARENT AND MATHEMATICAL SIMULATION OF ITS ENERGY GRADIENT     2 ABSTRACT   The objective was to evaluate the performance of the Agropolo model MC20 microsprinkler under different hydraulic conditions, generating information for a better design of micro-irrigation systems and water management in irrigated areas. The conduction of the hydraulic project to simulate the energy gradient in lateral lines, considered information determined through the choice of project components. The pairs of values ​​referring to flow and pressure were extracted from the manufacturer's commercial catalog and, from these, the flow-pressure curve was generated, where the simulation was performed using the Algebraic Method - Christiansen (MA) and Iterative Method (SBS) – Back-Step. For both methods, the microsprinkler behaved similarly, when subjected to conditions suggested by the manufacturer, in a spacing between emitters of 5.2 m, using polyethylene tubes with an internal diameter of 13 mm and a working pressure of 20 mca, admitting a 10% pressure variation. The uniformity of pressure (CUp) and flow (CUq) coefficients were calculated, both with values ​​above 95%, demonstrating the excellence in the performance of the emitter.   Keywords: hydraulic, mathematical modeling, discharge coefficient.