Comparison between forecasts of reference evapotranspiration and ETo values calculated using data from different climatic conditions

2020 ◽  
Author(s):  
Ghaieth Ben Hamouda ◽  
Francesca Ventura ◽  
Daniele Zaccaria ◽  
Khaled M. Bali ◽  
Richard L. Snyder
Keyword(s):  
Reference Evapotranspiration ◽  
Irrigation Management ◽  
Climatic Conditions ◽  
Physical Models ◽  
Dew Point ◽  
Water Losses ◽  
Plant Canopies ◽  
Crucial Component ◽  
And Performance ◽  
Using Data

<p>Evapotranspiration is the transfer of water from the earth's surface to the atmosphere. It comprises the sum of water losses to atmosphere due to the processes of evaporation of moisture from soil, water bodies and wet plant canopies, and the transpiration of water from plants. Forecasts of this crucial component of the hydrologic cycle can be very valuable for growers, farm managers, irrigation practitioners, water resource planners and managers, and reservoir operators for their planning, allocation, delivery and scheduling decisions, as well as to hydrologic scientists for research purposes. Verifying the reliability of models’ forecasts is among the critical tasks for development and performance evaluation of physical models. In fact, the verification allows understanding the models’ behavior, and evaluating their applicability and dependability. The US National Weather Service (NWS) has released a product that provides forecasts of reference evapotranspiration (FRET) at 2.5-km grid resolution for the entire continental US. In this study, a comparison is made between ETo estimates from FRET and ETo values calculated by the California Irrigation Management Information System (CIMIS) for 68 days during summer 2019. Both the FRET forecasts and ETo values were obtained from NWS and CIMIS, respectively, on the basis of 15 CIMIS locations that are representative of different climatic conditions in California. In addition, air temperature, dew point temperature, relative humidity, wind speed, and vapor pressure deficit (VPD) data were also collected/calculated from the NWS and CIMIS websites to analyze the sensitivity of FRET forecasts to predictions of these parameters. All FRET forecasts were performed with timescales of 1, 3, 5 and 7 days. Statistical indices were calculated to assess the dependability of FRET values. They showed a good correlation of the FRET model outputs with CIMIS ETo data, with some differences depending on the climatic characteristics of selected weather stations’ locations, suggesting that FRET data could be valuable for anticipating near-future water demand and improve irrigation management in California.</p>

scholarly journals Evapotranspiration and crop coefficients of melon plants measured by lysimeter and estimated according to FAO 56 methodology

2013 ◽  
Vol 33 (5) ◽  
pp. 929-939 ◽  
Author(s):  
Talyana K. de Melo ◽  
José F. de Medeiros ◽  
José E. Sobrinho ◽  
Vladimir B. Figueiredo ◽  
Paulo S. de Souza
Keyword(s):  
Reference Evapotranspiration ◽  
Irrigation Management ◽  
Climatic Conditions ◽  
Climatic Data ◽  
And Performance ◽  
Crop Coefficients ◽  
The City ◽  
Adequate Management ◽  
Monteith Equation ◽  
Statistical Indicators

Aiming at contributing to an adequate management of water resources, this study aimed to analyze and compare evapotranspiration (ETc) and crop coefficients (Kc) of melon plants measured by a lysimeter and estimated according to the FAO 56 methodology, in the city of Mossoró, state of Rio Grande do Norte (RN), Brazil. In order to measure ETc, weighing lysimeters with an area of 2.25m² were used, with two repetitions. The Penman-Monteith equation parameterized by FAO was used to estimate the reference evapotranspiration, and crop coefficients were those recommended in FAO-56 Bulletin adjusted to local climatic conditions. The required climatic data and lysimeter measurements were collected by an automatic weather station installed at the site. The results were compared by means of statistical indicators: of precision (r), of accuracy (d), and performance (c), in daily and weekly intervals. The data estimated by the FAO 56 methodology were adjusted optimally to the values measured by the lysimeters in accordance with index "c" in the two time scales assessed, indicating the potential of the method proposed by FAO to irrigation management in the climatic conditions of Agripole Assú-Mossoró.

scholarly journals ESTUDO COMPARATIVO ENTRE METODOLOGIAS DE ESTIMATIVA DA EVAPOTRANSPIRAÇÃO DE REFERÊNCIA PARA LOCALIDADES DO NORTE DE MINAS GERAIS

Irriga ◽  
2022 ◽  
Vol 1 (4) ◽  
pp. 714-721
Author(s):  
Lucas da Costa Santos ◽  
Lucas Santos do Patrocínio Figueiró ◽  
Alex Xavier Ribeiro Andrade ◽  
Antônio Costa Ferreira Neto ◽  
Caroline Salezzi Bonfá
Keyword(s):  
Meteorological Data ◽  
Irrigation Management ◽  
Absolute Error ◽  
Minas Gerais ◽  
Climatic Conditions ◽  
Empirical Methods ◽  
The North ◽  
And Performance ◽  
Evapotranspiration Estimation ◽  
E Mail

ESTUDO COMPARATIVO ENTRE METODOLOGIAS DE ESTIMATIVA DA EVAPOTRANSPIRAÇÃO DE REFERÊNCIA PARA LOCALIDADES DO NORTE DE MINAS GERAIS     LUCAS DA COSTA SANTOS1; LUCAS SANTOS DO PATROCÍNIO FIGUEIRÓ1; ALEX XAVIER RIBEIRO DE ANDRADE1; ANTÔNIO COSTA FERREIRA NETO1 E CAROLINE SALEZZI BONFÁ1   1 Departamento de Agronomia, Universidade Federal dos Vales do Jequitinhonha e Mucuri – UFVJM, Campus JK, Rodovia MGT 367-KM 583, nº 5000, Alto da Jacuba. CEP: 39.100-000, Diamantina, Minas Gerais, Brasil. E-mail: [email protected];[email protected];[email protected]; [email protected]; [email protected].     1 RESUMO   A determinação da evapotranspiração é imprescindível para a prática racional da irrigação, o que tem conduzido à formulação de diversas equações para estimativa desta importante variável meteorológica. Nesse sentido, faz-se necessário estudos comparativos com estas equações de modo a avaliar, localmente, sua aplicabilidade. Em linha com o exposto, objetivou-se comparar, para as condições climáticas de Salinas e Januária (ambos situados no Norte de Minas Gerais, Brasil), métodos empíricos de estimativa da evapotranspiração com o método padrão de Penman-Monteith (FAO56). Para tanto, utilizou-se dados meteorológicos de cinco anos (2016 a 2020) obtidos do Instituto Nacional de Meteorologia (INMET). Para a análise comparativa foram utilizados os seguintes indicadores estatísticos: coeficientes de determinação (R²) e correlação (r), erro absoluto médio (EAM), raiz do erro quadrado médio (REQM), índice de concordância (d) e índice de desempenho (c). Os resultados obtidos demonstram que, para as duas localidades avaliadas, o método de Blaney-Criddle apresenta o melhor desempenho para a estimativa da evapotranspiração, por outro lado, as equações de Hargreaves-Samani e Priestley-Taylor exibiram performance insatisfatória.   Palavras-chave: métodos empíricos, demanda hídrica de cultivos, manejo da irrigação.     SANTOS, L. C.; FIGUEIRÓ, L. S. P.; ANDRADE, A. X. R.; FERREIRA NETO, A. C.; BONFÁ, C. B. COMPARATIVE STUDY BETWEEN REFERENCE EVAPOTRANSPIRATION ESTIMATION METHODOLOGIES FOR NORTHERN MINAS GERAIS LOCATIONS     2 ABSTRACT   The determination of evapotranspiration is essential for the rational practice of irrigation, which has led to the formulation of several equations to estimate this important meteorological variable. In line with the above objective was to compare, for the climatic conditions of Salinas and Januária (both located in the North of Minas Gerais, Brazil), empirical methods for estimating evapotranspiration with the standard method of Penman-Monteith (FAO56). For this purpose, meteorological data for five years (2016 to 2020) obtained from the National Institute of Meteorology (INMET) were used. For the comparative analysis, the following statistical indicators were used: coefficients of determination (R²) and correlation (r), mean absolute error (EAM), root mean square error (REQM), agreement index (d) and performance index (c). The results obtained demonstrate that, for the two locations evaluated, the Blaney-Criddle method presents the best performance for estimating evapotranspiration, on the other hand, the Hargreaves-Samani and Priestley-Taylor equations showed unsatisfactory performance.   Keywords: crop water demand, empirical methods, irrigation management.

scholarly journals AVALIAÇÃO DO COEFICIENTE DO TANQUE CLASSE “A” NA ESTIMATIVA DA EVAPOTRANSPIRAÇÃO DE REFERÊNCIA NO BAIXO SÃO FRANCISCO, SE

Irriga ◽  
2018 ◽  
Vol 1 (1) ◽  
pp. 47
Author(s):  
Inajá Francisco De Sousa ◽  
Gregório Guirado Faccioli ◽  
Antenor De Oliveira Aguiar Netto
Keyword(s):  
San Francisco ◽  
Irrigation Management ◽  
Technical Literature ◽  
Class A ◽  
Great Performance ◽  
River Region ◽  
Scientific Technical ◽  
Dry Seasons ◽  
And Performance ◽  
Using Data

AVALIAÇÃO DO COEFICIENTE DO TANQUE CLASSE “A” NA ESTIMATIVA DA EVAPOTRANSPIRAÇÃO DE REFERÊNCIA NO BAIXO SÃO FRANCISCO, SE  INAJÁ FRANCISCO DE SOUSA1; GREGÓRIO GUIRADO FACCIOLI2 E ANTENOR DE OLIVEIRA AGUIAR NETTO1 1 Professor Doutor, Departamento de Engenharia Agronômica da Universidade Federal de Sergipe – UFS. [email protected]; [email protected] Professor Doutor, Departamento de Engenharia Agrícola da Universidade Federal de Sergipe – UFS. [email protected]                                                                                                                         1 RESUMO A literatura técnica científica cita diversos métodos para estimativa do coeficiente do tanque Classe “A” (Kp) visando a obtenção da evapotranspiração de referência (ETo), a qual é de importância vital no manejo da água na agricultura. A maioria desses métodos leva em conta a umidade relativa do ar, a área da bordadura e a velocidade do vento. O método do tanque de Classe “A” é simples e consiste na utilização de um tanque de evaporação direta, cheio de água, onde são feitas medidas em milímetros da água evaporada entre uma leitura e outra. A (ETo) é um fator relevante para quem usa a irrigação como um meio de suprir as necessidades hídricas das culturas, principalmente em regiões semiáridas. Este estudo teve como objetivo a determinação de coeficientes do tanque Classe “A” (Kp), através dos métodos  de Snyder (1992), Pereira et al. (1995), Cuenca (1989), e Allen et al. (1998), em seguida foi feita a estimativa da (ETo) utilizando os dados da evaporação do tanque Classes "A" (ECA), para as condições da região do baixo rio São Francisco do Estado de Sergipe. Os métodos foram avaliados nos períodos anual, chuvoso e seco referente ao ano de 2014. Posteriormente foram feitas análise de correlação da (ETo) estimada por cada método frente a (ETo) estimada pelo modelo de Pemann-Montheith. Em seguida determinou-se os coeficientes de determinação (r2), correlação (r), concordância (d) de Willmott (1982) e de desempenho (c). Os resultados obtidos evidenciaram que nos período anual, seco e chuvoso, todos os métodos apresentaram ótimo desempenho. As correlações realizadas tomando como modelo padrão Penamn-Monteith versus os métodos empregados, mostraram resultados não satisfatórios, apresentando baixa correlação. Palavras Chave: Evapotranspiração, manejo de irrigação, índices estatísticos.  SOUSA, I. F. de; FACCIOLI, G. G.; NETTO, A. de O. A.EVALUATION OF CLASS “A” TANK COEFICIENT ESTIMATE EVAPOTRANSPIRATION DOW REFERENCE IN SAN FRANCISCO, SE     2 ABSTRACT The scientific technical literature cites several methods to estimate the Class “a” tank coefficient (Kp) in order to obtain the reference evapotranspiration (ETo), which is vitally important in water management in agriculture. Most of these methods takes into account the relative humidity, the area surround and wind speed. The  Class "A" tank method is simple and consists in using a direct evaporation tank full of water, where measurements are made in millimeters of water evaporated from a reading to another. A (ETo) is an important factor for those who use irrigation as a means to supply the water needs of crops, particularly in semi-arid regions. This study aimed to determine "A" class tank coefficients (Kp) through Snyder methods (1992), Pereira et al. (1995), Cuenca (1989), and Allen et al. (1998). Then, an estimate (ETo) was made by using data from the evaporation of Class "A" (ACE), for the conditions of the lower São Francisco River region in the State of Sergipe. The methods were evaluated in the annual wet and dry seasons for the year 2014. Later a correlation analysis was performed (ETo), estimated by each method front (ETo), estimated by the Pemann-Montheith model. The coefficients of determination (r2), correlation (r), agreement (d) of Willmott (1982) and performance (c) were also determined. The results showed that along the annual dry and rainy season, all methods showed great performance. In the correlations performed by using the Penamn-Monteith model as a standard versus the methods used, the results were not satisfactory, with a low correlation. Keywords: Evapotranspiration, irrigation management, statistical rates.

scholarly journals Evaluation of empirical methods to estimate reference evapotranspiration in Uberaba, State of Minas Gerais, Brazil

2012 ◽  
Vol 32 (5) ◽  
pp. 875-888 ◽  
Author(s):  
Giovani L. de Melo ◽  
André L. T. Fernandes
Keyword(s):  
Standard Method ◽  
Reference Evapotranspiration ◽  
Potential Evapotranspiration ◽  
Minas Gerais ◽  
Climatic Conditions ◽  
Empirical Methods ◽  
Monthly Data ◽  
And Performance ◽  
Simple Statistical Analysis ◽  
Climatic Elements

Evapotranspiration is the process of water loss of vegetated soil due to evaporation and transpiration, and it may be estimated by various empirical methods. This study had the objective to carry out the evaluation of the performance of the following methods: Blaney-Criddle, Jensen-Haise, Linacre, Solar Radiation, Hargreaves-Samani, Makkink, Thornthwaite, Camargo, Priestley-Taylor and Original Penman in the estimation of the potential evapotranspiration when compared to the Penman-Monteith standard method (FAO56) to the climatic conditions of Uberaba, state of Minas Gerais, Brazil. A set of 21 years monthly data (1990 to 2010) was used, working with the climatic elements: temperature, relative humidity, wind speed and insolation. The empirical methods to estimate reference evapotranspiration were compared with the standard method using linear regression, simple statistical analysis, Willmott agreement index (d) and performance index (c). The methods Makkink and Camargo showed the best performance, with "c" values of 0.75 and 0.66, respectively. The Hargreaves-Samani method presented a better linear relation with the standard method, with a correlation coefficient (r) of 0.88.

scholarly journals Alternative Methods of Reference Evapotranspiration for Brazilian Climate Types

2018 ◽  
Vol 33 (3) ◽  
pp. 567-578 ◽  
Author(s):  
Bruno César Gurski ◽  
Daniela Jerszurki ◽  
Jorge Luiz Moretti de Souza
Keyword(s):  
Reference Evapotranspiration ◽  
Climatic Conditions ◽  
Least Square ◽  
Alternative Methods ◽  
Climate Type ◽  
Critical Gap ◽  
Climatic Regions ◽  
Sunshine Hours ◽  
And Performance ◽  
Semi Arid

Abstract The choice of consistent alternative methods is essential for the improvement of reference evapotranspiration (ETo) estimation for different climatic regions. Due to a critical gap in knowledge concerning the most adequate alternative ETo methods for the climatic conditions in Paraná, Brazil, this study aimed to test and to evaluate the main estimation alternative methods (Thornthwaite - EToTH; Camargo - EToC; Hargreaves and Samani - EToHS; Linacre - EToL; and, Budyko - EToB) for the subtropical (Cfb) and semi-arid (Bsh) climate types in Brazil. We compared our results with standard EToPM (Penman-Monteith) estimated between 1970 and 2015, using the minimum and maximum air temperature (T), sunshine hours (n), relative humidity (RH) and wind speed (U2). Least square regression analysis of ETo estimated by alternative methods vs EToPM were used to calibrate the methods for each analyzed climate type. The performance of calibrated and noncalibrated methods was evaluated by index of agreement “d” and performance “c”, root mean square error (RMSE) and mean error (ME). Our results showed the importance of calibration process of alternative methods for the improvement of ETo estimations in Brazil. The Hargreaves and Samani and Linacre calibrated methods showed better performance in the subtropical and semi-arid climates, respectively. Also, the Linacre and Budyko calibrated methods were particularly robust in subtropical and semi-arid climates, outlining the importance of continuous measurements of T used in the EToL and EToB modeling effort. The results presented here showed the importance to calibrate the alternative methods on ETo estimations and outlined the need for improvement and proposition of new ETo methods based on a limited number of climatic variables commonly available in subtropical and semi-arid climates in Brazil.

Determinants of Control System Design in Divisionalized Firms

2004 ◽  
Vol 79 (3) ◽  
pp. 545-570 ◽  
Author(s):  
Margaret A. Abernethy ◽  
Jan Bouwens ◽  
Laurence van Lent
Keyword(s):  
Control System ◽  
System Design ◽  
Performance Measures ◽  
Simultaneous Equation ◽  
Equation Model ◽  
Control System Design ◽  
Information Asymmetries ◽  
Endogenous Variables ◽  
And Performance ◽  
Using Data

We investigate two determinants of two choices in the control system of divisionalized firms, namely decentralization and use of performance measures. The two determinants are those identified in the literature as important to control system design: (1) information asymmetries between corporate and divisional managers and (2) division interdependencies. We treat decentralization and performance measurement choices as endogenous variables and examine the interrelation among these choices using a simultaneous equation model. Using data from 78 divisions, our results indicate that decentralization is positively related to the level of information asymmetries and negatively to intrafirm interdependencies, while the use of performance measures is affected by the level of interdependencies among divisions within the firm, but not by information asymmetries. We find some evidence that decentralization choice and use of performance measures are complementary.

scholarly journals Experiments on Energy-Efficient Evaporative Cooling Systems for Poultry Farm Application in Multan (Pakistan)

2021 ◽  
Vol 13 (5) ◽  
pp. 2836
Author(s):  
Khawar Shahzad ◽  
Muhammad Sultan ◽  
Muhammad Bilal ◽  
Hadeed Ashraf ◽  
Muhammad Farooq ◽  
...  
Keyword(s):  
Heat Stress ◽  
Low Cost ◽  
Evaporative Cooling ◽  
Thermal Exposure ◽  
Climatic Conditions ◽  
The Body ◽  
Dew Point ◽  
Sweat Glands ◽  
Cooling Systems ◽  
Humidity Index

Poultry are one of the most vulnerable species of its kind once the temperature-humidity nexus is explored. This is so because the broilers lack sweat glands as compared to humans and undergo panting process to mitigate their latent heat (moisture produced in the body) in the air. As a result, moisture production inside poultry house needs to be maintained to avoid any serious health and welfare complications. Several strategies such as compressor-based air-conditioning systems have been implemented worldwide to attenuate the heat stress in poultry, but these are not economical. Therefore, this study focuses on the development of low-cost and environmentally friendly improved evaporative cooling systems (DEC, IEC, MEC) from the viewpoint of heat stress in poultry houses. Thermodynamic analysis of these systems was carried out for the climatic conditions of Multan, Pakistan. The results appreciably controlled the environmental conditions which showed that for the months of April, May, and June, the decrease in temperature by direct evaporative cooling (DEC), indirect evaporative cooling (IEC), and Maisotsenko-Cycle evaporative cooling (MEC) systems is 7–10 °C, 5–6.5 °C, and 9.5–12 °C, respectively. In case of July, August, and September, the decrease in temperature by DEC, IEC, and MEC systems is 5.5–7 °C, 3.5–4.5 °C, and 7–7.5 °C, respectively. In addition, drop in temperature-humidity index (THI) values by DEC, IEC, and MEC is 3.5–9 °C, 3–7 °C, and 5.5–10 °C, respectively for all months. Optimum temperature and relative humidity conditions are determined for poultry birds and thereby, systems’ performance is thermodynamically evaluated for poultry farms from the viewpoint of THI, temperature-humidity-velocity index (THVI), and thermal exposure time (ET). From the analysis, it is concluded that MEC system performed relatively better than others due to its ability of dew-point cooling and achieved THI threshold limit with reasonable temperature and humidity indexes.

Capacity Planning for Cluster Tools of Wafer Fabrication Plant

2010 ◽  
Vol 450 ◽  
pp. 365-368
Author(s):  
James C. Chen ◽  
Chia Wen Chen ◽  
Kou Huang Chen ◽  
Chien Hsin Lin
Keyword(s):  
Capacity Planning ◽  
Production Costs ◽  
Wafer Fabrication ◽  
Total Production ◽  
Output Rate ◽  
Cluster Tools ◽  
And Performance ◽  
Using Data ◽  
Capital Intensive

Wafer fabrication is a capital intensive industry. A 12-inch wafer fabrication plant needs a typical investment of US$ 3 billion, and the equipment cost constitutes about two-thirds to three-quarters of the total production costs. Therefore, capacity planning is crucial to the investment and performance of wafer fabrication plants. Several formulae are presented to calculate the required number of machines with sequential, parallel, and batch processing characteristics, respectively. An AutoSched AP simulation model using data from real foundry fabrication plants is used in a case study to evaluate the performance of the proposed formulae. Simulation results indicate that the proposed formulae can quickly and accurately calculate the required number of cluster tools leading to the required monthly output rate.

scholarly journals Defining an Industry: What is the Size and Scope of the Australian Building and Construction Industry

1970 ◽  
Vol 10 (1-2) ◽  
pp. 119-131 ◽  
Author(s):  
Gerard De Valence
Keyword(s):  
Construction Industry ◽  
Performance Model ◽  
Cluster Approach ◽  
Industry Cluster ◽  
Traditional Structure ◽  
Economic Contribution ◽  
And Performance ◽  
Using Data ◽  
Traditional Industry ◽  
Different Characteristics

This is a reprint from Vol 1, no 1, which has not previously been available in electronic format.The analysis and understanding of the conduct and performance of an industry begins with a study of its structure. However, before analysing an industry's structure it is necessary to define the industry and identify its size, scope and scale to establish its true economic contribution. This paper discusses the size and scope of the Australian building and construction industry, firstly froma traditional industry economics approach by firm size and business characteristics using data fron three construction industry surveys done over 15 years by the ABS. Secondly, data from an industry 'cluster' perspective is shown. The objective of the paper is to compare the differences found in industry size and scope in the structure-conduct-performance approach and the alternative industry cluster approach. Each model reveals different characteristics of the industry. The conclusion finds that the building and construction industry is a case where the traditional structure-conduct-performance model cannot be easily applied. 

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