Estimativa da evapotranspiração real pelo emprego do algoritmo SEBAL e imagem Landsat 5-TM na Bacia do Acaraú, CE

• Ano de defesa: 2007
• Autor(a) principal: Meireles, Marcos
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Palavras-chave em Português: Irrigação e drenagem; SEBAL; Micrometeorologia; Sensoriamento remoto; Micrometeorology; Remote sensing
• Link de acesso: http://www.repositorio.ufc.br/handle/riufc/18632

Elaboration of natural resources mapping is difficult due to large spatial and temporal variability of them. In the least decay, remote sensing is widely used do make this because the lower survey costs. The main goal of this work is to estimate daily evapotranspiration of the Araras Norte Irrigated Perimeters and evaporation of four reservoirs (Jaibaras, Paulo Sarasate, Edson Queiroz and Forquilha) located in the middle part of the Acaraú basin. The actual evapotranspiration was quantified from spectral satellite data on the basis of the energy balance approach. The LANDSAT 5 Thematic Mapper 30 m, resolution satellite image taken on 01 september 2004, was obtained from Instituto Nacional de Pesquisas Espaciais (INPE). Satellite image was processed and piled up using Erdas Imagine 8.5 Demo. Hour and daily evapotranspiration was estimated using SEBAL (Surface Energy Balance Algorithm for Land) algorithm, which is based on energy balance between incoming and outgoing solar radiation. Among generated remote sensing maps are: temperature (ºC), Albedo (a), Normalized Difference Vegetation Index (NDVI), net radiation (Rn), sensible heat flux (H), latent heat flux (lET) and hour evapotranspiration (ETH). Based on ETH the evaporative fraction was estimated throughout the relationship of ET for pixel at the satellite image time (mm.h-1) and reference crop ET by Penman-Montheith method. Results showed that the lowest albedo and the highest evapotranspiration rates were registered in the reservoir (7.5 mm.dia-1); the spatial distribution of soil heat flux presented a similar distribution of soil predominant types in the studied region. Also, It was observed the influence of water flow in the repair zone soil humidity, once it was registered, in these areas, values of NDVI and daily evapotranspiration similar to those observed in irrigated areas. Irrigated District of Araras Norte showed an ETdiária around 6.5 mm.dia-1. It was clear that SEBAL approach has a high potential in study of desertification, changes in cover vegetation and land use at basin scales; since latent heat and evapotranspiration can be a good indication of changed cover vegetation change.