Advanced Evapotranspiration Methods and Applications最新文献

{"title":"Nonlinear Evapotranspiration Modeling Using Artificial Neural Networks","authors":"Sirisha Adamala","doi":"10.5772/INTECHOPEN.81369","DOIUrl":"https://doi.org/10.5772/INTECHOPEN.81369","url":null,"abstract":"Reference evapotranspiration (ET o ) is an important and one of the most difficult components of the hydrologic cycle to quantify accurately. Estimation/measure-ment of ET o is not simple as there are number of climatic parameters that can affect the process. There exists copious conventional (direct and indirect) and non con-ventional/soft computing (artificial neural networks, ANNs) methods for estimating ET o . Direct methods have the limitations of measurement errors, expensive, impracticality of acquiring point measurements for spatially variable locations, whereas the indirect methods have the limitations of unavailability of all necessary climate data and lack of generalizability (needs local calibration). In contrast to conventional methods, soft computing models can estimate ET o accurately with minimum climate data which have advantages over limitations of conventional ET o methods. This chapter reviews the application of ANN methods in estimating ET o accurately for 15 locations in India using six climatic variables as input. The performance of ANN models were compared with the multiple linear regression (MLR) models in terms of root mean squared error, coefficient of determination and ratio of average output and target ET o values. The results suggested that the ANN models performed better as compared to MLR for all locations. backpropagation Broyden-Fletcher-Goldfarb-Shanno","PeriodicalId":189693,"journal":{"name":"Advanced Evapotranspiration Methods and Applications","volume":"41 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128351730","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Concept and Consequence of Evapotranspiration for Sustainable Crop Production in the Era of Climate Change","authors":"Rajan Bhatt, A. Hossain","doi":"10.5772/INTECHOPEN.83707","DOIUrl":"https://doi.org/10.5772/INTECHOPEN.83707","url":null,"abstract":"The chapter provides an inclusive information related to the adverse effect of climate change on sustainable crop production through understanding evaporation, transpiration as well as evapotranspiration. It is anticipated that water availability in arid and semi-arid regions across the world will decrease, due to lack of rainfall and increase the temperature which leads to increase in the dry areas. Since climate change will impact on soil water balance that leads to change in evaporation and plant transpiration. While, with the increasing temperature, lack of precipitation and soils water unavailability, crop production will likely to decrease through shortening the crop growth cycle. While soils with high water holding capacity and crop cultivars which are tolerant to adverse effect as well as the application of improved management strategies will be better to reduce the impact of drought. Similarly, if the irrigated areas will be expanded, the total crop production will be increased that ultimately lead to increase the food security of increasing population.","PeriodicalId":189693,"journal":{"name":"Advanced Evapotranspiration Methods and Applications","volume":"44 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-02-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114077353","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An Advanced Evapotranspiration Method and Application","authors":"Homin Kim, J. Kaluarachchi","doi":"10.5772/INTECHOPEN.81047","DOIUrl":"https://doi.org/10.5772/INTECHOPEN.81047","url":null,"abstract":"Estimating evapotranspiration is an important component in the monitoring of agricultural and environmental systems. This chapter will focus on the developing evapotranspiration method using general meteorological data and Normalized Difference Vegetation Index (NDVI). The proposed model in this chapter will be refined by using both the complemen tary relationship and the Budyko framework. The relative evaporation parameter in the complementary relationship will be derived by using precipitation, potential evapotranspiration, and NDVI based on that the Budyko framework can support the complementary relationship. It is also important to determine whether the proposed model can compete and deliver accuracy similar to remote sending method in the aspect of application. The results in the first phase showed the proposed model could be a powerful methodology to estimate ET among the ground-based method. In the second phase, a nonlinear correction function was proposed to better describe the complementary relationship. We will also demonstrate that the use of ET is a better approach for drought estimations than considering reference ET. More importantly, the advantage of the proposed model is that it can comprehensively consider both effects of precipitation and vegetation information. Taken together, this chapter has extended our knowledge of ET to support water resource management.","PeriodicalId":189693,"journal":{"name":"Advanced Evapotranspiration Methods and Applications","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126305774","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Influence of Landsat Revisit Frequency on Time-Integration of Evapotranspiration for Agricultural Water Management","authors":"R. Trezza, R. Allen, A. Kilic, I. Ratcliffe, M. Tasumi","doi":"10.5772/INTECHOPEN.80946","DOIUrl":"https://doi.org/10.5772/INTECHOPEN.80946","url":null,"abstract":"The objective of this study was to explore the improvement in accuracy of estimates for evapotranspiration (ET) over complete growing seasons and monthly periods, when more frequent Landsat imagery is made available. Conversely, we explored the reduction in accuracy in ET estimates when frequency of Landsat imagery was reduced. The study was implemented by conducting a series of METRIC applications for two Landsat WRS path overlap areas, one in southern Idaho (paths 39 and 40) during 2000, and a second one in Nebraska (paths 29 and 30) during 2002, years when two fully functioning satellites, Landsat 5 and Landsat 7, were in orbit. The results indicated that high frequency imagery provided by two satellites covering a WRS path overlap was more able to capture the impacts of rapid crop development and harvest, and evaporation associated by wetting events. That data set simulated a nominal four-day revisit time. Three-simulated 16-day revisit data sets created using a single Landsat series for a single path were unable to produce monthly and growing season ET due to the lack of sufficient number of images to even begin the time-integration process. This emphasizes the need to maintain two Landsat satellites in orbit and the high value of four-day revisit times. Limiting the data set to one path and two satellites (eight-day revisit) underestimated growing season ET accordingly by about 8% on average. Error in monthly ET was relatively high when image availability was limited to that for an eight-day revisit. This is due to the importance of timing of images to identify key inflection points in the ETrF curves and to capture special events such as wetting events from irrigation and rain or from water stress or cuttings, as in the case of forage crops. Results suggest that a four-day revisit time as represented by the full-run (run 1) of our analysis provides robustness in the development of time-integrated ET estimates over months and growing seasons, and is a valuable backstop for mitigation of clouded images over extended periods.","PeriodicalId":189693,"journal":{"name":"Advanced Evapotranspiration Methods and Applications","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116830449","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evapotranspiration from Green Infrastructure: Benefit, Measurement, and Simulation","authors":"Youcan Feng","doi":"10.5772/INTECHOPEN.80910","DOIUrl":"https://doi.org/10.5772/INTECHOPEN.80910","url":null,"abstract":"Green infrastructure (GI) is a common solution for stormwater management in an urban environment, with attached environmental benefits like flood control, urban heat island relief, adaptations to climate change, biodiversity protection, air pollution reduction, and food production. Evapotranspiration (ET) controls the GI’s hydrologic performance and affects all related benefits. Essentially, ET constrains the turnover of moisture storage and determines the demand for supple-mental irrigation and then the cost-effectiveness of a GI project. Considering the spatial heterogeneousness of an urban space and the GI’s multi-layer designs, the classic ET equations have challenges in representing the ET variations from GI units. The underperformance of the existing ET models is partly due to the lack of corresponding high-quality field observations for each GI type in various urban settings. This chapter, therefore, summarizes the current research progress and existing challenges regarding the benefit, measurement, and simulation of ET process from GI.","PeriodicalId":189693,"journal":{"name":"Advanced Evapotranspiration Methods and Applications","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129163776","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Field-Scale Estimation of Evapotranspiration","authors":"J. Moorhead","doi":"10.5772/INTECHOPEN.80945","DOIUrl":"https://doi.org/10.5772/INTECHOPEN.80945","url":null,"abstract":"Evapotranspiration (ET) is a major component of the water cycle, which makes it an integral part of water resources management, especially in arid and semiarid environments. ET data are used for water management, irrigation scheduling, various modeling activities, and much more. Some areas of scarce water resources place limitations on water use, which are typically determined from various modeling approaches. As many models use ET as an input, or for validation, accurate ET data is essential to ensure accurate model outputs. In addition, most water management practices are done at the field scale; ET data of a similar scale is needed. Many ET measurement or estimation methods exist and vary widely in approach, instrumentation, complexity, and purpose. A lysimeter is considered the standard for ET measurement and is the most accurate. Other, more portable options are available, such as eddy covariance, scintillometer, Bowen ratio, and remote sensing, all capa-ble of estimating actual field ET within approximately 30% of actual values. Although other methods may not be as accurate as a lysimeter, each has benefits in certain situations. Depending on the purpose, the level of accuracy may be suitable. ET estimation methods are constantly evolving, and accuracy should continually improve further.","PeriodicalId":189693,"journal":{"name":"Advanced Evapotranspiration Methods and Applications","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133165027","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}