气候变化领域集成服务门户(CCPortal): Spatio-temporal patterns of energy exchange and evapotranspiration during an intense drought for drylands in Brazil

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DOI	10.1016/j.jag.2019.101982
	Spatio-temporal patterns of energy exchange and evapotranspiration during an intense drought for drylands in Brazil
	dos Santos C.A.C.; Mariano D.A.; das Chagas A. do Nascimento F.; da C. Dantas F.R.; de Oliveira G.; Silva M.T.; da Silva L.L.; da Silva B.B.; Bezerra B.G.; Safa B.; de S. Medeiros S.; Neale C.M.U.
发表日期	2020
ISSN	15698432
卷号	85
英文摘要	The Caatinga biome, located in the northeastern region of Brazil, is the most populated dryland region on the planet and extremely vulnerable to land degradation due to climatological and anthropogenic factors. Energy partitioning substantially influences the local climate and affects the water cycle, which is of utmost importance for the economy and livelihood of the region. Recently, eddy covariance (EC) towers were installed in the area; thus, the scientific community can thoroughly assess the water and energy fluxes over this unique biome. While EC towers have a high degree of accuracy, they only measure energy fluxes over a small land footprint. Given the biome spatial heterogeneity, the use of EC-based techniques has the limitation of not comprehensively representing water and energy fluxes profiles over the entire region. Incorporating remote sensing (RS) data into the landscape analysis is a feasible solution to overcome this issue, given that satellite data can capture the phenomena represented by the EC measurements across large spatial scales. Our research studied the capability of the Surface Energy Balance Algorithm for Land (SEBAL) and MOD16-ET products to represent the EC measurements regarding energy and mass exchange, with an ultimate objective of applying the best approach to assess these fluxes regionally. We applied the SEBAL model using only remote sensing data from the Moderate Resolution Imaging Spectroradiometer (MODIS) sensor. The MOD16-ET model uses a different approach but is also based on MODIS data. Our analysis was based on three years (2014–2016) of data, which was limited to the availability of the EC tower data. We found that for the EC-based measurements, energy balance closure (EBC) achieved an average of 0.84, which is considerably high for the region. This is possibly due to the EC tower being installed on a preserved Caatinga plot, with reduced heterogeneity and higher plant density. When analyzing RS-based products to represent ET profiles in the region, we found that the SEBAL model accurately represented water fluxes during the wet season but not the dry season, whereas the MOD16-ET showed a better agreement with EC-based water fluxes throughout all the seasons. SEBAL inaccuracy in drylands is partially due to the narrow range between the cold and hot pixels in an image, as the algorithm relies on this range for input parameters, especially in the dry season. Therefore, we concluded that MOD16-ET is capable of better-representing water fluxes in the Caatinga region. We analyzed the fluxes regionally and quantified annual ET for the three years. These results are especially relevant for local policymakers on dealing with water and landscape issues in a region where the livelihood and well-being of the population is inextricably bound to water availability. © 2019 Elsevier B.V.
英文关键词	Caatinga; Drought; Eddy covariance; Land degradation; MODIS; SEBAL
语种	英语
scopus关键词	algorithm; annual variation; climate change; drought; eddy covariance; evapotranspiration; hydrological cycle; land degradation; MODIS; pixel; spatiotemporal analysis; Brazil; Embryophyta
来源期刊	International Journal of Applied Earth Observation and Geoinformation
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/156433
作者单位	Academic Unity of Atmospheric Sciences, Federal University of Campina Grande, Campina Grande, Paraiba, Brazil; Daugherty Water for Food Global Institute, University of Nebraska, Lincoln, NE, United States; Federal Rural University of Semiarid, Mossoró, Rio Grande do Norte, Brazil; School of Natural Resources, University of Nebraska, Lincoln, NE, United States; National Institute of Semiarid, Campina Grande, PB, Brazil; Department of Geography and Atmospheric Science, University of Kansas, Lawrence, KS, United States; Department of Atmospheric and Climate Sciences, Federal University of Rio Grande do Norte, Natal, Rio Grande do Norte, Brazil
推荐引用方式 GB/T 7714	dos Santos C.A.C.,Mariano D.A.,das Chagas A. do Nascimento F.,et al. Spatio-temporal patterns of energy exchange and evapotranspiration during an intense drought for drylands in Brazil[J],2020,85.
APA	dos Santos C.A.C..,Mariano D.A..,das Chagas A. do Nascimento F..,da C. Dantas F.R..,de Oliveira G..,...&Neale C.M.U..(2020).Spatio-temporal patterns of energy exchange and evapotranspiration during an intense drought for drylands in Brazil.International Journal of Applied Earth Observation and Geoinformation,85.
MLA	dos Santos C.A.C.,et al."Spatio-temporal patterns of energy exchange and evapotranspiration during an intense drought for drylands in Brazil".International Journal of Applied Earth Observation and Geoinformation 85(2020).