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

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.

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

Irriga ◽

10.15809/irriga.2021v1n4p714-721 ◽

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.

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DESEMPENHO DE MÉTODOS NA ESTIMATIVA DE EVAPOTRANSPIRAÇÃO DE REFERÊNCIA PARA O ESTADO DA PARAÍBA, BRASIL

Irriga ◽

10.15809/irriga.2016v21n3p481-490 ◽

2018 ◽

Vol 21 (3) ◽

pp. 481 ◽

Cited By ~ 1

Author(s):

Geffson De Figueredo Dantas ◽

Vinicius Mendes Rodrigues de Oliveira ◽

Alexandre Barcellos Dalri ◽

Luiz Fabiano Palaretti ◽

Miqueias Gomes dos Santos ◽

...

Keyword(s):

Comparative Analysis ◽

Standard Method ◽

Reference Evapotranspiration ◽

Weather Data ◽

Coefficient Of Determination ◽

Empirical Methods ◽

Satisfactory Performance ◽

Time Period ◽

And Performance ◽

Level Of Agreement

DESEMPENHO DE MÉTODOS NA ESTIMATIVA DE EVAPOTRANSPIRAÇÃO DE REFERÊNCIA PARA O ESTADO DA PARAÍBA, BRASIL GEFFSON DE FIGUEREDO DANTAS1; VINICIUS MENDES RODRIGUES DE OLIVEIRA2; ALEXANDRE BARCELLOS DALRI3; LUIZ FABIANO PALARETTI3; MIQUEIAS GOMES DOS SANTOS4 E ROGÉRIO TEXEIRA DE FARIA3 1 Licenciado em Ciências Agrárias, Doutorando em Agronomia (Ciência do Solo), Departamento de Engenharia Rural, FCAV-Unesp/ Jaboticabal, SP, [email protected] Engº Agrônomo, Doutorando em Engenharia Agrícola, Departamento de Engenharia Agrícola, UFV/Viçosa, MG, [email protected] Engº Agrícola, Prof. Doutor, Departamento de Engenharia Rural, FCAV-Unesp/Jaboticabal, SP, [email protected], [email protected], [email protected] Engº Agrônomo, Doutorando em Agronomia (Ciência do Solo), Departamento de Engenharia Rural, FCAV-Unesp/Jaboticabal, SP, [email protected] 1 RESUMO O métodos padrão de estimativa da evapotranspiração de referência (ET0) FAO Penman-Monteith (PM) emprega variáveis meteorológicas as quais nem sempre estão disponíveis à maioria dos produtores rurais. Assim, o presente trabalho teve por objetivo avaliar seu desempenho e aferir se necessário, para as condições da Paraíba, diferentes métodos para a estimativa diária de ET0, comparando-os com o método padrão FAO Penman-Monteith. Utilizou-se uma série histórica de 17 anos de dados meteorológicos do INMET de quatro cidades do Estado da Paraíba. Os métodos avaliados foram os de Hargreaves-Samani (HS), Blaney-Criddle (BC), Camargo (C) e Jensen-Haise (JH). Para análise comparativa entre o método PM e os outros métodos, foi realizada a análise de correlação e regressão linear e do coeficiente de determinação (R²). Para a exatidão dos métodos empíricos, foi realizada a análise para a determinação do índice de concordância (d) e do índice de desempenho (c). A ET0, obtida pelos quatro métodos empíricos obtiveram desempenho satisfatório, o método HS para a mesorregião do agreste não necessitou de ajustes, já os métodos JH, C e HS para as mesorregiões litoral, borborema e sertão necessitaram de ajuste para melhor acurácia em relação ao método padrão. Palavras-chave: calibração, irrigação, Penman-Monteith DANTAS, G. de F.; OLIVEIRA, V. M. R. de; DALRI, A. B.; PALARETTI, L. F.; SANTOS, M. G. dos; FARIA, R. T. dePERFORMANCE OF METHODS FOR ESTIMATING ET0 IN PARAÍBA STATE, BRAZIL 2 ABSTRACT The standard method for estimating reference evapotranspiration (ET0), FAO Penman-Monteith (PM) employs meteorological variables which are not always available to most farmers. Thus, this study aimed to evaluate and benchmark their performance if necessary, to the conditions of Paraíba, different methods for daily ET0 were estimated by comparing them with the standard FAO Penman-Monteith method. We used a time period of 17 years of weather data INMET in four cities in the state of Paraíba. The methods evaluated were the Hargreaves-Samani (HS), Blaney-Criddle (BC), Camargo (C) and Jensen-Haise (JH). For comparative analysis between the PM method and other methods, correlation analysis and linear regression to determine the coefficients of the equation (Y = a + bx) and the coefficient of determination (R²) was performed. For accuracy of empirical methods, the analysis was performed to determine the level of agreement (d) and performance index (c). The estimation of reference evapotranspiration, obtained by four empirical for meso-Paraíba PB methods, achieved satisfactory performance, the HS method for the rough mesoregion needed no adjustments since the JH, C and HS methods for meso coast, borborema and hinterland need adjustment for better accuracy compared to the standard method. Keywords: calibration, irrigation, evapotranspiration

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

10.5194/egusphere-egu2020-372 ◽

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&#8217; forecasts is among the critical tasks for development and performance evaluation of physical models. In fact, the verification allows understanding the models&#8217; 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&#8217; locations, suggesting that FRET data could be valuable for anticipating near-future water demand and improve irrigation management in California.</p>

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Assessment of empirical methods for estimation of reference evapotranspiration in the Brazilian Savannah

Australian Journal of Crop Science ◽

10.21475/ajcs.19.13.07.p1569 ◽

2019 ◽

pp. 1094-1104

Author(s):

Lucas da Costa Santos ◽

Guilherme Henrique Terra Cruz ◽

Frank Freire Capuchinho ◽

Jeffersom Vieira José ◽

Elton Fialho dos Reis

Keyword(s):

Air Temperature ◽

Standard Method ◽

Reference Evapotranspiration ◽

Meteorological Data ◽

Reference Method ◽

The State ◽

Coefficient Of Determination ◽

Mean Bias Error ◽

Bias Error ◽

Empirical Methods

Evapotranspiration can be sufficiently estimated when meteorological data are available to implement robust models such as Penman-Monteith (PM). However, due to data scarcity, alternative approaches are necessary. In this context, this study aims to compare the reference evapotranspiration (ETo) obtained from the PM standard method with eight empirical equations to identify the simplest method that can be alternative to the reference method (Penman Monteith method) for ten places in state of Goiás (located in west-central Brazil, Brazilian Savanna). To estimate the ETo, air temperature and relative humidity air, wind speed, sunshine and solar radiation data, which were obtained from the data platform National Institute of Meteorology and the Meteorological and Hydrological System of the State of Goiás, were used. For comparison of empirical methods with PM standard method, we used the following statistical indicators: slope and intercept coefficients (β0 and β1) of regressions equations, the coefficient of determination (r²), Pearson's correlation (r), mean bias error (MBE), root mean square error (RMSE) concordance index refined (dr) and performance index (Pi). Our results indicated that the Turc method is the best option for the state of Goiás when meteorological data are not suffeciently available to use the standard PM method. On the other hand, the method of Romanenko did not present acceptable performance in nine of the ten studied localities. Therefore, its use is advised only in the municipality of the Itumbiara. Among evaluated methods the Hargreaves-Samani method is the best alternative, when there is only air temperature data.

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EVAPOTRANSPIRAÇÃO DE REFERÊNCIA EM FUNÇÃO DOS EXTREMOS DA TEMPERATURA DO AR NO ESTADO DO RIO DE JANEIRO

Irriga ◽

10.15809/irriga.2016v21n3p449-465 ◽

2018 ◽

Vol 21 (3) ◽

pp. 449 ◽

Cited By ~ 4

Author(s):

Anderson Amorim Rocha Santos ◽

Gustavo Bastos Lyra ◽

Guilherme Bastos Lyra ◽

Evaldo Paiva Lima ◽

José Leonaldo De Souza ◽

...

Keyword(s):

Air Temperature ◽

Rio De Janeiro ◽

Reference Evapotranspiration ◽

Global Radiation ◽

The State ◽

Southeastern Brazil ◽

Temperature Extremes ◽

Empirical Methods ◽

And Performance ◽

E Mail

EVAPOTRANSPIRAÇÃO DE REFERÊNCIA EM FUNÇÃO DOS EXTREMOS DA TEMPERATURA DO AR NO ESTADO DO RIO DE JANEIRO ANDERSON AMORIM ROCHA SANTOS1; GUSTAVO BASTOS LYRA2; GUILHERME BASTOS LYRA3; EVALDO PAIVA LIMA4; JOSÉ LEONALDO DE SOUZA5 E RAFAEL COLL DELGADO2 1 Engenheiro Agrônomo, Mestre em Engenharia de Biossistemas, Escola de Engenharia, Universidade Federal Fluminense – UFF, Campus da Praia Vermelha, 24210-240, Niterói, Rio de Janeiro, Brasil, e-mail: [email protected] Meteorologistas, Professores Doutores do Departamento de Ciências Ambientais, Instituto de Florestas, Universidade Federal Rural do Rio de Janeiro – UFRRJ, Campus UFRRJ, 23897-000, Seropédica, Rio de Janeiro, Brasil, e-mail: [email protected]; [email protected] Engenheiro Agrônomo, Professor Doutor do Centro de Ciências Agrárias, Universidade Federal de Alagoas – UFAL, BR-104, 57100-000, Rio Largo, Alagoas, Brasil, e-mail:[email protected] 4 Meteorologista, Pesquisador do Centro Nacional de Pesquisa de Solos, Empresa Brasileira de Pesquisa Agropecuária – EMBRAPA, Rua Jardim Botânico 1024, 22460-000, Rio de Janeiro, Rio de Janeiro, Brasil, e-mail: [email protected] Meteorologista, Professor Doutor do Centro de Ciências Agrárias, Universidade Federal de Alagoas – UFAL, BR-104, 57100-000, Rio Largo, Alagoas, Brasil, e-mail: [email protected] 1 RESUMO A aplicação do método de Penman-Monteith FAO56 (PM-FAO56) para estimativa da evapotranspiração de referência (ETo) requer observações de diversos elementos meteorológicos. A maior parte das estações meteorológicas não realiza medidas de todos os elementos, o que restringe a aplicação do PM-FAO56. O objetivo foi avaliar o desempenho dos métodos empíricos de Thornthwaite, Camargo, Hargreaves-Samani, Jensen-Haise e Makkink na estimativa de ETo em função dos extremos de temperatura do ar no estado do Rio de Janeiro (RJ). Foram utilizadas séries meteorológicas entre oito e 34 anos de 10 estações convencionais pertencentes ao Instituto Nacional de Meteorologia localizadas no RJ. As estimativas decendiais e mensais de ETo pelos métodos empíricos foram comparadas com ETo determinada por PM-FAO56 (padrão) para se avaliar a exatidão (Erro Padrão de Estimativa - EPE e Índice de Willmott - d), precisão (coeficiente de determinação - R²) e o desempenho (índice c de Camargo e Sentelhas) dos métodos. Independente da escala de tempo avaliada, o método de Makkink mostrou estimativas com maior exatidão (d > 0,82 e EPE < 0,68 mm d-1), precisão (R² > 0,88) e desempenho (índice c > 0,85) nas estações caracterizadas com clima úmido, subúmido, subúmido seco com pequeno excedente hídrico. Nas demais estações, clima subúmido seco com excedente nulo e semiárido, o método de Hargreaves-Samani teve melhor desempenho (índice c > 0,85). Os métodos de Thornthwaite e Camargo apresentaram estimativas com exatidão (d > 0,90 e EPE < 0,72 mm d-1) e desempenho (índice c > 0,76) entre os melhores e podem ser usados para estimativa de ETo no RJ. As menores exatidões (d < 0,73 e EPE > 1,38 mm d-1) e desempenhos (0,51 < índice c < 0,75) das estimativas foram proporcionadas por Jensen-Haise para todas as estações e escalas de tempo, não sendo recomendado sua aplicação no estado do RJ. Os métodos de Hargreaves-Samani, Jensen-Haise e Makkink devem ser ajustados às condições climáticas do RJ. Palavras-Chave: Penman-Monteith, radiação solar global, amplitude térmica SANTOS, A. A. R.; LYRA, G.B.; LYRA, G.B.; LIMA, E. P.; SOUZA, J. L.; DELGADO, R. C.ESTIMATES OF THE REFERENCE EVAPOTRANSPIRATION USING AIR TEMPERATURE EXTREMES IN THE STATE OF THE RIO DE JANEIRO, SOUTHEASTERN BRAZIL 2 ABSTRACT The use of the Penman-Monteith FAO56 method (PM-FAO 56) to estimate reference evapotranspiration (ETo) requires several weather elements. However, most weather stations don’t measure all the elements, which restricts the application of PM-FAO 56. The aim of this article was to evaluate the performance of five empirical methods (Thornthwaite, Camargo, Hargreaves-Samani, Jensen-Haise and Makkink) to estimate ETo using air temperature extremes in the state of the Rio de Janeiro (RJ). Times series of weather elements between eight and 34 years from 10 conventional stations of the Brazilian National Institute of Meteorology located in RJ were used. The ten-day and monthly estimates of ETo by empirical methods were compared to ETo determined by PM-FAO 56 (default) to evaluate the accuracy (Standard Error of the Estimate - SEE and Willmott index - d), precision (coefficient of determination - R²) and performance (Camargo and Sentelhas – c Index) of the methods. Independent of the time scale, the Makkink method showed the highest accuracies (d > 0.82 and SEE < 0.68 mm d-1), precision (R² > 0.88) and performance (c Index > 0.85) on the stations, characterized with humid, sub-humid, dry sub-humid with small water surplus. For the other stations, semiarid and dry sub-humid climate with no surplus, the Hargreaves-Samani method had the best performance (c Index > 0.85). The Thornthwaite and Camargo methods presented accuracy (d > 0.90 and SEE < 0.72 mm d-1) and performance (Index c > 0.76) between the top and can be used to estimate ETo in RJ. For all stations and time scales, the worst accuracies (d < 0.73 and SEE > 1.38 mm d-1) and performance (0.51 < Index c < 0.75) estimates were provided by the Jensen-Haise method, so it is not recommended its application in RJ state. The Hargreaves-Samani, Jensen-Haise and Makkink methods should be fitted to the climatic conditions of RJ. Keywords: Penman-Monteith, solar global radiation, temperature amplitude

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

Engenharia Agrícola ◽

10.1590/s0100-69162013000500005 ◽

2013 ◽

Vol 33 (5) ◽

pp. 929-939 ◽

Cited By ~ 3

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.

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Alternative Methods of Reference Evapotranspiration for Brazilian Climate Types

Revista Brasileira de Meteorologia ◽

10.1590/0102-7786333015 ◽

2018 ◽

Vol 33 (3) ◽

pp. 567-578 ◽

Cited By ~ 3

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.

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Empirical methods for reference evapotranspiration estimation

Scientia Agraria Paranaensis ◽

10.18188/sap.v19i3.21487 ◽

2020 ◽

Vol 19 (3) ◽

pp. 203-210

Author(s):

Oswaldo Palma Lopes Sobrinho ◽

Wady Lima Castro Júnior ◽

Leonardo Nazário Silva dos Santos ◽

Gerlange Soares da Silva ◽

Álvaro Itaúna Schalcher Pereira ◽

...

Keyword(s):

Reference Evapotranspiration ◽

Meteorological Data ◽

Physical Phenomenon ◽

Climatic Conditions ◽

Alternative Methods ◽

Empirical Methods ◽

Class A ◽

Evapotranspiration Estimation ◽

Almost All ◽

Meteorological Elements

The reference evapotranspiration (ETo) is a parameter applied in meteorological, climatological and hydrological studies being of great importance for the planning, management and management of water resources. Due to the need for knowledge about the loss of water from vegetated surfaces, researchers have developed a variety of methods for estimating ETo, some of which are well accepted, while others are criticized, such as the Penman-Monteith-FAO (PM-FAO) meteorological data, which is not always available by limiting its use. The PM-FAO method has been used for decades to be considered internationally and most appropriate for ETo estimates. This method represents the physical phenomenon of evapotranspiration that involves almost all meteorological elements analyzed in automatic and conventional meteorological stations. On the other hand, when this method is impossible to apply due to the lack of some input data, alternative methods are justified (Hargreaves-Samani, Blaney-Criddle, Priestley-Taylor, Jensen-Haise, Camargo, Makkink, Kharrufa , Linacre, Class A tank, Thornthwaite and solar radiation) according to soil and climatic conditions.

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Radial Growth Response of European Larch Provenances to Interannual Climate Variation in Poland

Forests ◽

10.3390/f12030334 ◽

2021 ◽

Vol 12 (3) ◽

pp. 334

Author(s):

Norbert Szymański ◽

Sławomir Wilczyński

Keyword(s):

Radial Growth ◽

Climatic Factors ◽

Principal Component ◽

Climatic Conditions ◽

Growth Responses ◽

European Larch ◽

Temperature And Precipitation ◽

Provenance Trials ◽

High Precipitation ◽

Climatic Elements

The present study identified the similarities and differences in the radial growth responses of 20 provenances of 51-year-old European larch (Larix decidua Mill.) trees from Poland to the climatic conditions at three provenance trials situated in the Polish lowlands (Siemianice), uplands (Bliżyn) and mountains (Krynica). A chronology of radial growth indices was developed for each of 60 European larch populations, which highlighted the interannual variations in the climate-mediated radial growth of their trees. With the aid of principal component, correlation and multiple regression analysis, supra-regional climatic elements were identified to which all the larch provenances reacted similarly at all three provenance trials. They increased the radial growth in years with a short, warm and precipitation-rich winter; a cool and humid summer and when high precipitation in late autumn of the previous year was noted. Moreover, other climatic elements were identified to which two groups of the larch provenances reacted differently at each provenance trial. In the lowland climate, the provenances reacted differently to temperature in November to December of the previous year and July and to precipitation in September. In the upland climate, the provenances differed in growth sensitivity to precipitation in October of the previous year and June–September. In the mountain climate, the provenances responded differently to temperature and precipitation in September of the previous year and to precipitation in February, June and September of the year of tree ring formation. The results imply that both climatic factors and origin (genotype), i.e., the genetic factor, mediate the climate–growth relationships of larch provenances.

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Characteristics of Phomopsis juglandina (Sacc.) Hohn. Associated with Dieback of Walnut in the Climatic Conditions of Southern Romania

Agronomy ◽

10.3390/agronomy11010046 ◽

2020 ◽

Vol 11 (1) ◽

pp. 46

Author(s):

Cristina Mihaescu ◽

Daniel Dunea ◽

Adrian Gheorghe Bășa ◽

Loredana Neagu Frasin

Keyword(s):

Growth Temperature ◽

Potential Evapotranspiration ◽

Optimal Growth ◽

Climatic Conditions ◽

Cultural Characteristics ◽

Optimal Growth Temperature ◽

Conidial State ◽

Optimal Ph

Phomopsis juglandina (Sacc.) Höhn., which is the conidial state of Diaporthe juglandina (Fuckel) Nitschke, and the main pathogen causing the dieback of branches and twigs of walnut was recently detected in many orchards from Romania. The symptomatological, morphological, ultrastructural, and cultural characteristics, as well as the pathogenicity of an isolate of this lignicolous fungus, were described and illustrated. The optimum periods for infection, under the conditions prevailing in Southern Romania, mainly occur in the spring (April) and autumn months (late September-beginning of October). Strong inverse correlations (p < 0.001) were found between potential evapotranspiration and lesion lengths on walnut branches in 2019. The pathogen forms two types of phialospores: alpha and beta; the role of beta phialospores is not well known in pathogenesis. In Vitro, the optimal growth temperature of mycelial hyphae was in the range of 22–26 °C, and the optimal pH is 4.4–7. This pathogen should be monitored continuously due to its potential for damaging infestations of intensive plantations.

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