Desempenho de Método de Estimativa da Temperatura Média Diária: Um Estudo em Áreas com Forte Pressão Antrópica (Performance of Method for Estimation of the Mean Daily Air Temperature: A Study in Areas with Strong Anthropogenic Pressure)

Este trabalho teve como objetivo avaliar o desempenho de métodos alternativos utilizados na estimativa da temperatura do ar média diária na região do Polo de irrigação Petrolina-Juazeiro. Os principais dados meteorológicos utilizados nas avaliações são oriundos de observações feitas nas estações climatológicas de Bebedouro – PE e Mandacaru – BA, pertencentes à Embrapa Semiárido. As análises estatísticas foram realizadas empregando regressão linear e seus respectivos coeficientes de determinação (R2). Os resultados obtidos com a aplicação do método recomendado pela FAO (Food and Agriculture Organization) mostram que a evolução temporal da temperatura é extremamente sensível às mudanças no uso e cobertura da terra. O aumento no teor de umidade na baixa troposfera, decorrente da expansão agrícola em área de caatinga, contribui para a absorção da energia calorífica e elevação da temperatura noturna (temperatura mínima). A B S T R A C T The development of this work aimed to evaluate the performance of alternative methods used to estimate the daily mean air temperature in the Petrolina-Juazeiro irrigation area. The main meteorological data used in the evaluations are observations made at the climatologic stations of Bebedouro – PE and Mandacaru – BA, which belong to Embrapa Semiarid. The statistical analyses were performed using linear regression and their respective coefficients of determination (R2). The results obtained by applying the method recommended by FAO (Food and Agriculture Organization) show that the temperature temporal evolution is extremely sensitive to changes in land use and coverage. The increase in the moisture content in the lower troposphere, due to agricultural expansion in the caatinga area, contributes toward absorption of heat energy and nighttime temperature (minimum temperature) rise. Key-Words: agricultural expansion, climate changes, anthropogenic pressures, semiarid, daily mean air temperature.

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Empirical Equations to Estimate Evapotranspiration in Mosul City

Tikrit Journal of Engineering Sciences ◽

10.25130/tjes.27.4.10 ◽

2020 ◽

Vol 27 (4) ◽

pp. 98-102

Author(s):

Haqqi Yasin ◽

Luma Abdullah

Keyword(s):

Wind Speed ◽

Relative Humidity ◽

Air Temperature ◽

Reference Evapotranspiration ◽

Sunshine Duration ◽

Food And Agriculture ◽

Food And Agriculture Organization ◽

Daily Data ◽

Daily Sunshine ◽

Measured Wind Speed

Average daily data of solar radiation, relative humidity, wind speed and air temperature from 1980 to 2008 are used to estimate the daily reference evapotranspiration in the Mosul City, North of Iraq. ETo calculator software with the Penman Monteith method standardized by the Food and Agriculture Organization is used for calculations. Further, a nonlinear regression approach using SPSS Statistics is utilized to drive the daily reference evapotranspiration relationships in which ETo is function to one or more of the average daily air temperature, actual daily sunshine duration, measured wind speed at 2m height and relative humidity

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Bicluster CC Algoritm Analysis to Identify Patterns of Food Insecurity in Indonesia

Jurnal Matematika Statistika dan Komputasi ◽

10.20956/jmsk.v17i2.12057 ◽

2020 ◽

Vol 17 (2) ◽

pp. 325-338

Author(s):

Raditya Novidianto ◽

Rini Irfani

Keyword(s):

Food Insecurity ◽

Agricultural Sector ◽

Parameter Tuning ◽

Mean Square ◽

Calorie Consumption ◽

Food And Agriculture ◽

Food And Agriculture Organization ◽

The Mean ◽

Best Parameter ◽

The One

Indonesia is known as an agricultural country. This means that most of the population work in the agricultural sector related to food. However, food insecurity still occurs in Indonesia. With the COVID-19 pandemic, the Food and Agriculture Organization (FAO) stated that there was a threat of food scarcity which had an impact on food insecurity conditions. This would undermine the second goal of the SDGs, which is to end hunger and create sustainable agriculture. The purpose of this study was to determine the spatial pattern of food insecurity in each province in Indonesia using the bicluster method. The data used are data from Susenas and Sakernas by BPS in 2019. Several studies show that the bicluster method with the CC algorithm shows that each province group has a different characteristic pattern. In the bicluster approach, the researcher runs parameter tuning to select the best parameter based on the Mean Square Residual in Volume (MSR / V). The CC algorithm tries to get a bicluster with a low MSR value, therefore the best parameter is the one that produces the smallest MSR / V value, in this study the smallest MSR / V is 0,01737 with δ = 0,01. The application of the CC biclustering algorithm to the food insecurity structure in Indonesia results in 5 bicluster. Bicluster 1 consists of 15 provinces with 8 variables, Bicluster 2 consists of 10 provinces with 5 variables, Bicluster 3 consists of 3 provinces with 7 variables, Bicluster 4 consists of 4 provinces with 4 variables and Bicluster 5 consists of 2 provinces with 5 variables. Biculster 4 represents a cluster of food insecurity areas with the characteristics of the bicluster P0, P1, P2 and calorie consumption of less than 1400 KKAL.

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Comparison of meteorological data, related to reference evapotranspiration, from conventional and automatic stations in the Sertão and Agreste regions of Pernambuco, Brazil

DYNA ◽

10.15446/dyna.v88n216.86372 ◽

2021 ◽

Vol 88 (216) ◽

pp. 176-183

Author(s):

Iug Lopes ◽

Miguel Julio Machado Guimarães ◽

Juliana Maria Medrado de Melo ◽

Ceres Duarte Guedes Cabral de Almeida ◽

Breno Lopes ◽

...

Keyword(s):

Reference Evapotranspiration ◽

Meteorological Data ◽

Global Solar Radiation ◽

Concordance Index ◽

Good Relationship ◽

Food And Agriculture ◽

Food And Agriculture Organization ◽

Daily Scale ◽

Weather Stations ◽

Meteorological Elements

The objective was to perform a comparative study of the meteorological elements data that most cause changes in the reference Evapotranspiration (ETo, mm) and its own value, of automatic weather stations AWS and conventional weather stations CWS of the Sertão and Agreste regions of Pernambuco State. The ETo was calculated on a daily scale using the standard method proposed by the Food and Agriculture Organization (FAO), Penman-Monteith (FAO-56). The ETo information obtained from AWS data can be used to update the weather database of stations, since there is a good relationship between the ETo data obtained from CWS and AWS, statistically determined by the Willmott's concordance index (d > 0.7). The observed variations in the weather elements: air temperature, relative humidity, wind speed, and global solar radiation have not caused significant changes in the ETo calculation.

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Quantification of Environmental Flow Requirement for some Rivers in West Java

E3S Web of Conferences ◽

10.1051/e3sconf/202014807003 ◽

2020 ◽

Vol 148 ◽

pp. 07003

Author(s):

Waluyo Hatmoko ◽

Levina ◽

Radhika ◽

Amirwandi ◽

Rendy

Keyword(s):

Water Conservation ◽

Environmental Flow ◽

Dry Season ◽

Mean Flow ◽

West Java ◽

Food And Agriculture ◽

Food And Agriculture Organization ◽

Tennant Method ◽

The Mean ◽

Flow Requirement

Sustainable Development Goal (SDG). Water management is making a balance between water for livelihood and water as a resource. Environmental Flow Requirement (EFR) is water conservation, on the side of the water for livelihood, to sustain the river ecosystem. In Indonesia, the common quantification of EFR is dependable flow Q95%. However, there are alternative quantities: a) Guideline of irrigation states that 5% from the available water in the river is for environmental purposes; b) Adoption of the Tennant Method of using 10% of the mean flow; and recently Food and Agriculture Organization (FAO) in the framework of SDG proposed that in Java Island the EFR is from 40% to 50% of the mean annual flow. This paper discusses several ways of quantification of the EFR in Indonesia, and apply the different EFR quantities to Citarum, Cimanuk, and Cimandiri Rivers in West Java. It is concluded that EFR quantity according to FAO that might be suitable for the rivers in the pristine catchments in the southern part of West Java is too high for the rivers in the northern part of West Java which is heavily populated and maturely developed. Furthermore, the dependable flow of Q95% is found to be close to the quantity of FAO, but in the dry season, Q95% is more suitable. It is recommended using a modified FAO that combine with Q95% during the dry season.

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Combination of satellite imagery with meteorological data for estimating reference evapotranspiration

Revista de Teledetección ◽

10.4995/raet.2018.7688 ◽

2018 ◽

pp. 75

Author(s):

D. Montero ◽

F. Echeverry ◽

F. Hernández

Keyword(s):

Land Surface Temperature ◽

Land Surface ◽

Reference Evapotranspiration ◽

Meteorological Data ◽

Meteorological Station ◽

Significant Relation ◽

Food And Agriculture ◽

Food And Agriculture Organization ◽

Digital Elevation ◽

Weather Stations

The Food and Agriculture Organization of the United Nations (FAO) in its publication No. 56 of the Irrigation and Drainage Series presents the FAO Penman-Monteith procedure for the estimation of reference evapotranspiration from meteorological data, however, its calculation may be complicated in areas where there are no weather stations. This paper presents an evaluation of the potential of the Land Surface Temperature and Digital Elevation Models products derived from the MODIS and ASTER sensors, both on board the Terra EOS AM-1 satellite, for the estimation of reference evapotranspiration using the Penman-Monteith FAO-56, Hargreaves, Thornthwaite and Blaney-Criddle models. The four models were compared with the method proposed by FAO calculated with the observed data of a ground based meteorological station, finding a significant relation with the models Penman-Monteith FAO-56 and Hargreaves.

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Modelling albedo and specific balance of the Greenland ice sheet: calculations for the Søndre Strømfjord transect

Journal of Glaciology ◽

10.3189/s0022143000004160 ◽

1996 ◽

Vol 42 (141) ◽

pp. 305-317 ◽

Cited By ~ 4

Author(s):

Z. Zuo ◽

J. Oerlemans

Keyword(s):

Energy Balance ◽

Mass Balance ◽

Air Temperature ◽

Surface Albedo ◽

Meteorological Data ◽

Greenland Ice Sheet ◽

Mass Balance Models ◽

The Mean ◽

Energy Balance Models ◽

Wide Zone

AbstractGlacio-meteorological data obtained during the Greenland Ice Margin Experiment (GIMEX) investigations in West Greenland (the Søndre Strømfjord transect) have been used to test and calibrate energy-balance/mass-balance models for the ice/snow surface. The region is characterised by the development of a wide zone of low surface albedo in the course of the melting season. This zone was simulated in one of the energy-balance models by including the effect of surficial meltwater on albedo. Observed mass-balance and albedo data were used to constrain the models. Although all the models are capable of predicting the transect balance reasonably well, only the model with the meltwater albedo coupling, is able to reproduce the observed albedo pattern and mass-balance profile along the transect. By including the feedback between surficial meltwater and albedo in the model, the sensitivity of the specific balance to changes in air temperature is found to be greatest just below the equilibrium line (in contrast to what is generally found for valley glaciers). A 1 K warming of the air temperature would increase the mean ablation along the transect by 0.5 m w.e.year −1.

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Aufbereitung meteorologischer Daten zur Unterstützung einer globalen agrarmeteorologischen Beratung

10.5194/dach2022-229 ◽

2021 ◽

Author(s):

Joachim Namyslo

Keyword(s):

Air Temperature ◽

Cascade Model ◽

Earth System ◽

Crop Water ◽

Water Requirements ◽

Food And Agriculture ◽

Food And Agriculture Organization ◽

Applied Meteorology ◽

Hermite Spline ◽

Agricultural Meteorology

Im Rahmen einer agrarmeteorologischen Beratung ist die Berechnung der Verdunstung f&#252;r spezifische Agrarkulturen mit geeigneten Modellen m&#246;glichst auf einer st&#252;ndlichen Zeitskala erforderlich. Im DWD ist hierzu das Modell AMBAV (Agrarmeteorologisches Modell zur Berechnung der aktuellen Verdunstung) entwickelt worden und wird f&#252;r die nationale agrarmeteorologische Beratung operationell mit Vorhersagedaten und f&#252;r Wirkanalysen auch mit Klimadaten verwendet. Insbesondere hinsichtlich globaler Anwendungen liegen gemessene oder mit Klimamodellen berechnete meteorologische Datenzeitreihen h&#228;ufig nur f&#252;r eine t&#228;gliche Zeitskala, oder als Modelldaten f&#252;r ausgew&#228;hlte Elemente bestenfalls in einer 6-st&#252;ndigen Zeitskala, vor. Dies sind Tagesmittel oder Tagessummen (z.B. Wind bzw. Globalstrahlung und Niederschlag) sowie gegebenenfalls t&#228;gliche Extremwerte (Minimum und Maximum der Lufttemperatur, st&#228;rkste Tagesb&#246;e). Zur Bereitstellung st&#252;ndlicher Daten aus Tagesdaten wurde daher ein Pr&#228;prozessor entwickelt, der gemessene Stationsdaten (Modus &#8222;Station&#8220;) oder modellierte Daten globaler Modelle (Modus &#8222;Gitter&#8220;) verwendet. Dabei wurde vorausgesetzt, dass im Vorfeld einer Erarbeitung von zeitlichen Disaggregierungsverfahren keine umfangreichen Klimaanalysen durchgef&#252;hrt werden m&#252;ssen sondern weitestgehend auf Erfahrung zur&#252;ckgegriffen werden kann. Vorhandene Programme (z.B. MELODIST) konnten jedoch wegen teilweise anderer Zielstellung oder Datenanforderungen nicht ohne weiteres verwendet werden. So wurde z.B. f&#252;r die Tagessumme der Globalstrahlung auf das Angstr&#246;m-Verfahren (FAO, 1998), f&#252;r den Niederschlag auf das Kaskadenverfahren nach Olsson (1998), f&#252;r die Lufttemperatur auf den &#8222;sin-exp-Ansatz&#8220; nach Parton und Logan (1981) und f&#252;r den Wind auf die &#8222;normierte B&#246;en&#173;geschwindigkeit&#8220; (Verkaik, 2000) zur&#252;ckgegriffen. F&#252;r erforderliche Interpolationen werden das Newton-Verfahren und das &#8222;cubic hermite spline&#8220; verwendet. Die vorgestellten Verfahren werden mit Stationsdaten des ZAMF und beispielhaft mit Modelldaten des GFCS f&#252;r Madagaskar angewendet. Literatur FAO (Food and Agriculture Organization), 1998: Crop evaporation &#8211; Guidelines for computing crop water requirements. Irrigation and Drainage Paper 56, 300 p. Olsson, J., 1998: Evaluation of a scaling cascade model for temporal rainfall disaggregation. Hydrology and Earth System Sciences, 2, p.19-30. Parton, W.J. and J.A. Logan, 1981: A model for diurnal variation in soil and air temperature. Agricultural Meteorology, 23, p.205-216. Verkaik, J.W., 2000: Evaluation of two gustiness models for exposure correction calculations. Journal of Applied Meteorology, 39, p.1613-1626.

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Evapotranspiration and crop coefficient for potato in organic farming

Engenharia Agrícola ◽

10.1590/s0100-69162013000100020 ◽

2013 ◽

Vol 33 (1) ◽

pp. 201-211 ◽

Cited By ~ 5

Author(s):

Daniel F. de Carvalho ◽

Dione G. da Silva ◽

Hermes S. da Rocha ◽

Wilk S. de Almeida ◽

Eraldo da S. Sousa

Keyword(s):

Water Consumption ◽

Solanum Tuberosum L ◽

Meteorological Data ◽

Crop Coefficient ◽

Climatic Conditions ◽

Food And Agriculture ◽

Food And Agriculture Organization ◽

Historical Series ◽

The One ◽

Crop Coefficients

The aim of this study was to quantify the water consumption and the crop coefficients (Kc) for the potato (Solanum tuberosum L.), in Seropédica, Rio de Janeiro (RJ), Brazil, under organic management, and to simulate the crop evapotranspiration (ETc) using the Kc obtained in the field and the ones recommended by the Food and Agriculture Organization (FAO). The water consumption was obtained through soil water balance, using TDR probes installed at 0.15m and 0.30m deep. At the different stages of development, the Kc was determined by the ratio of ETc and reference evapotranspiration, obtained by Penman-Monteith FAO 56. The crop coefficients obtained were 0.35, 0.45, 1.29 and 0.63. The accumulated ETc obtained in the field was 109.6 mm, while the ETc accumulated from FAO's Kc were 142.2 and 138mm, respectively, considering the classical values and the values adjusted to the local climatic conditions. The simulation of water consumption based on meteorological data of historical series from 1961 to 2007 provided higher value of ETc when compared with the one obtained in the field. From the meteorological data of historical series, it was observed that the use of Kc recommended by FAO may overestimate the amount of irrigation water by 9%, over the same growing season.

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Estimating Solar Radiation Intensity from Other Meteorological Data

The Journal of Agriculture of the University of Puerto Rico ◽

10.46429/jaupr.v54i2.11100 ◽

1969 ◽

Vol 54 ◽

pp. 377-389

Author(s):

Modesto Capiel

Keyword(s):

Regression Analysis ◽

Solar Radiation ◽

Multiple Regression Analysis ◽

Multiple Regression ◽

Air Temperature ◽

Meteorological Data ◽

Solar Radiation Intensity ◽

Period Data ◽

The Mean ◽

Analysis Equation

Estimates of solar radiation (Ri) by 15-day periods were calculated from other available meteorological data by multiple regression analysis of Eo = f(Ri, u, Ta) ed), and then solving for Ri from the most significant equation of the model given above. Only solar radiation wind speed (u) and air temperature (Ta) were found to correlate significantly with Eo. The solution in terms of Ri (equation /4/) then was used to obtain estimates of solar radiation for 1- to 5-day periods. The mean ratio of estimated Ri to measured Ri approached unity (0.95), while the coefficient of variation was 8.9 percent, as compared to 5.1 percent for the original 15-day period data. It was found when these were compared to measured values that neglect of air temperature reduced precision of the estimates. Equation /4/ (the indirect solution) next was evaluated on the basis of foreign data, representing extreme meteorological conditions as those in Bet Dagan, Israel and Cristobal, Panamá. This equation also was compared at the same time to a direct solution of Ri by multiple regression analysis (equation /6/), a solution which directly minimizes the deviations about Ri. Statistical data are presented which compare the precision of the estimates by either equation (/4/ and /6/).

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Optimal Selection of Empirical Reference Evapotranspiration Method in 36 Different Agricultural Zones of China

Agronomy ◽

10.3390/agronomy12010031 ◽

2021 ◽

Vol 12 (1) ◽

pp. 31

Author(s):

Yong Yang ◽

Rensheng Chen ◽

Chuntan Han ◽

Zhangwen Liu ◽

Xiqiang Wang

Keyword(s):

Reference Evapotranspiration ◽

Meteorological Data ◽

Aridity Index ◽

Empirical Method ◽

Climatic Conditions ◽

Food And Agriculture ◽

Food And Agriculture Organization ◽

Temperature Method ◽

The Relationship ◽

Selection Of

The Food and Agriculture Organization has proposed the current version of the Penman–Monteith method (FAO56-PM) as the standard for calculating reference evapotranspiration (ET0); however, high meteorological data requirements limit its application in many areas. There is thus an urgent need to identify the best alternative empirical method to accurately calculate ET0 in regions that lack sufficient meteorological data. In this study, three temperature-based methods and five radiation-based methods were evaluated using ET0 values generated using the FAO56-PM method in 36 agricultural zones in China based on meteorological data from 823 stations, measured between 2011 and 2020. The results showed that the optimal temperature-based method and radiation-based method differed for different agricultural zones, and no one temperature method or radiation method could be suitable for all agricultural zones. The eight empirical methods were regionally calibrated to improve the ET0 calculation accuracy in the different zones. The relationship between the optimal methods and climatic conditions showed that the most reliable empirical method could be selected according to the local annual mean temperature and aridity index. The results provide useful guidance for the selection of reliable empirical ET0 methods in agricultural zones outside China.

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