An Australian comparison of Penman's potential evapotranspiration estimates and class A evaporation pan data

Soil Research ◽  
1992 ◽  
Vol 30 (1) ◽  
pp. 101 ◽  
Author(s):  
FHS Chiew ◽  
TA Mcmahon
Keyword(s):  
Linear Regression ◽  
Potential Evapotranspiration ◽  
Actual Evapotranspiration ◽  
Climatic Data ◽  
Regression Equations ◽  
Climatic Regions ◽  
Class A ◽  
Time Periods ◽  
Land Surfaces ◽  
Evaporation Pan

Estimates of potential evapotranspiration are required to serve as an aid for estimating actual evapotranspiration. Penman's combination equation is generally accepted as an appropriate method for estimating potential evapotranspiration. However, as all the climatic data required to calculate Penman's potential evapotranspiration are seldom available, potential evapotranspiration is more commonly approximated as a factor times standard evaporation pan reading. In this paper, linear regression equations relating Penman's potential evapotranspiration for land surfaces to Class A evaporation pan data over several time periods are developed for various climatic regions throughout Australia. The analyses indicate that the correlations between daily estimates of Penman's potential evapotranspiration and pan data are poor, and therefore, pan data should be treated with caution if used to approximate daily potential evapotranspiration. The correlations improve over longer time periods, and the equations developed for three-day and weekly totals may be used as a last resort to approximate potential evapotranspiration in areas where climatic data required to calculate potential evapotranspiration are not available.

MACROCLIMATIC MODEL FOR ESTIMATING MONTHLY SOIL TEMPERATURES UNDER SHORT-GRASS COVER IN CANADA

1973 ◽  
Vol 53 (3) ◽  
pp. 263-274 ◽  
Author(s):  
C. E. OUELLET
Keyword(s):  
Soil Temperature ◽  
Potential Evapotranspiration ◽  
Important Variable ◽  
Climatic Variables ◽  
Standard Errors ◽  
Climatic Data ◽  
Regression Equations ◽  
Grass Cover ◽  
Temperature Variations ◽  
Soil Temperatures

A macroclimatic model was developed to estimate monthly soil temperatures under short-grass cover. It involved multiple regression equations for each month and for each of six depths (1, 10, 20, 50, 100, and 150 cm). Data used were obtained from published records of soil temperature and corresponding climatic variables. They were from 41 stations over several years with station-years per regression varying from 88 to 226 according to depths and months. The climatic variables were related to air temperature, rainfall, snowfall, and potential evapotranspiration. An additional important variable was the estimated soil temperature of the previous month. The equations explain 70–96% of the soil temperature variations and the standard errors of estimate varied from 0.7 to 2.2 C. Temperatures estimated for 1 yr and eight stations with climatic data not used in the development of the equations departed from the observed values by less than 0.5, 1.0, and 2.0 C in 34, 62, and 92% of the cases, respectively. Errors resulting from the estimation of monthly normals by this model are expected to be generally less than 1.0 degree C.

scholarly journals Climatic water balance in Hamelmalo, Eritrea

2021 ◽  
pp. 69-76
Author(s):  
Mehari Gebreyesus ◽  
Arzu Rivera Garcia ◽  
Géza Tuba ◽  
Györgyi Kovács ◽  
Lúcia Sinka ◽  
...  
Keyword(s):  
Climate Change ◽  
Water Balance ◽  
Potential Evapotranspiration ◽  
Climatic Data ◽  
Total Production ◽  
Relative Air Humidity ◽  
Wide Range ◽  
Long Time ◽  
Time Changes ◽  
Evaporation Pan

Agricultural production is an important sector for peoples to live, but it is highly affected by climate change. To have a good production we need to understand the climatic parameters which adversely affect production. Hamelmalo, which is located in the semi-arid area of Eritrea, is vulnerable to climate change and this is realised in the total production loss. Nevertheless, there is no concrete reference about the climate of the region due to lack of data for a long time. Changes in precipitation (P), evapotranspiration (ET) and, implicitly, in the climatic water balance (CWB), are imminent effects of climate change. However, changes in the CWB, as a response to changes in P and ET, have not yet been analysed thoroughly enough in many parts of the world, including Eritrea. This study also explores the changes of the CWB in the Hamelmalo region, based on a wide range of climatic data (P, relative air humidity and evaporation pan necessary for computing potential evapotranspiration (PET) with the pan evaporation method) recorded at Hamelmalo from 2015-2019. This analysis shows that the annual cumulative CWB for Hamelmalo is negative in 67% of the years. The dry season without precipitation leads to negative CWB and the change in CWB only starts from the raining or crop season. Based on this recent study, 2015 had the highest PET and lowest P, and this resulted in the lowest CWB in the investigated period. Opposite to this, 2019 had lower PET and highest P, which led to the highest CWB. However, the monthly values of CWB did not correlate with the annual P or ET. On the base of our study, it can be concluded that PET and P were very variable in the investigated years and P was the most influential elements of CWB.

SINGLE-FACTOR LINEAR REGRESSION MODEL OF HODGKIN’S LYMPHOMA IN ADOLESCENTS

2017 ◽  
Vol 63 (2) ◽  
pp. 320-325
Author(s):  
Svetlana Kuleva ◽  
Svetlana Ivanova ◽  
Andrey Karitskiy ◽  
Darya Zvyagintseva
Keyword(s):  
Radiation Therapy ◽  
Linear Regression ◽  
Predictive Factors ◽  
Hodgkin’S Lymphoma ◽  
Risk Group ◽  
Hodgkin's Lymphoma ◽  
Regression Equations ◽  
Single Factor ◽  
Number Of Cycles ◽  
Selection Of

With the use of regression and dispersion analyzes conducted in this study it was possible to identify predictive factors that significantly worsen the prognosis of Hodgkin’s lymphoma in adolescents however constructed regression equations did not pass the quality assessment of the models, which did not allow them to be used for the construction of point and interval predictions. In a cohort of patients enrolled in the study a risk-adapted treatment program based on the risk group for stratification was conducted. Negative aspects of the results of our study could be related to the already selected volume of the program for these patients. In turn our analysis proves the validity of the selection of therapeutic loads (a number of cycles of polychemotherapy, doses of radiation therapy) depending on the risk group, into which the adolescent is stratified.

scholarly journals Annual Actual Evapotranspiration Estimation via GIS Models of Three Empirical Methods Employing Remotely Sensed Data for the Peloponnese, Greece, and Comparison with Annual MODIS ET and Pan Evaporation Measurements

2021 ◽  
Vol 10 (8) ◽  
pp. 522
Author(s):  
Stavroula Dimitriadou ◽  
Konstantinos G. Nikolakopoulos
Keyword(s):  
Time Scale ◽  
Gradual Decrease ◽  
Actual Evapotranspiration ◽  
Pan Evaporation ◽  
Empirical Methods ◽  
Remotely Sensed Data ◽  
Upward Trend ◽  
Class A ◽  
Evapotranspiration Estimation ◽  
Class A Pan

Actual evapotranspiration (ETa) has been insufficiently investigated in Greece. This study aimed to estimate annual ETa by empirical methods (Turc, modified Turc, and Coutagne) for the Peloponnese, Greece, a Mediterranean testbed, between 2016–2019, four of the warmest years since the preindustrial era, and compare them to MODIS ET. Furthermore, measurements of annual pan evaporation (Epan) were performed for two Class A pan stations in the Peloponnese with different reliefs and conditions. The empirical methods and statistical formulae (RMSD, MB, and NMB) were developed as models in ArcMap. The outcomes of the Turc method resembled MODIS ET ranges for all years, followed by those of Coutagne. The estimates by the modified Turc method were almost identical to MODIS ET. Therefore, the modified Turc method can be used as an alternative to MODIS ET (and vice versa) for the Peloponnese for 2016–2019. Moreover, the Epan at Patras University station (semiurban, low elevation) exhibited an upward trend resembling the trends of the empirical methods over the study years, whereas the Epan at Ladonas station (higher elevation, lakeside) required investigation on a monthly time scale. Additionally, the gradual decrease of pan-water icing at Ladonas in December (from 20 d in 2016 to 0 d in 2019) could imply an undergoing decrease in snowpack storage retention across the mountains of the Peloponnese.

Methodology of Estimation of Fire Separation Distances between Construction Facilities by Calculation

2020 ◽  
Vol 1006 ◽  
pp. 93-100
Author(s):  
Vadym Nizhnyk ◽  
Yurii Feshchuk ◽  
Volodymyr Borovykov
Keyword(s):  
Mathematical Model ◽  
Heat Flux ◽  
Linear Regression ◽  
Ignition Temperature ◽  
Oil Products ◽  
Regression Equations ◽  
Fire Load ◽  
Literary Sources ◽  
Tabular Method

Based on analysis of appropriate literary sources we established that estimation of fire separation distances was based of two criteria: heat flux and temperature. We proposed to use “ignition temperature of materials” as principal criterion when determining fire separation distances between adjacent construction facilities. Based on the results derived while performing complete factorial we created mathematical model to describe trend of changing fire separation distances depending on caloric power of fire load (Q), openings factor of the external enclosing structures (k) and duration of irradiation (t); moreover, its adequacy was confirmed. Based on linear regression equations we substantiated calculation and tabular method for the determination of fire separation distances for a facility being irradiated which contains combustible or otherwise non-combustible façade and a facility where liquid oil products turn. We developed and proposed general methodology for estimation of fire separation distances between construction facilities by calculation.

The energy balance of a US Class A evaporation pan

2013 ◽  
Vol 182-183 ◽  
pp. 314-331 ◽  
Author(s):  
Wee Ho Lim ◽  
Michael L. Roderick ◽  
Michael T. Hobbins ◽  
Suan Chin Wong ◽  
Graham D. Farquhar
Keyword(s):  
Energy Balance ◽  
Class A ◽  
Evaporation Pan

scholarly journals A MODEL FOR ESTIMATING ACTUAL EVAPOTRANSPIRATION FROM POTENTIAL EVAPOTRANSPIRATION

1975 ◽  
Vol 6 (3) ◽  
pp. 170-188 ◽  
Author(s):  
K. J. KRISTENSEN ◽  
S. E. JENSEN
Keyword(s):  
Water Content ◽  
Soil Water ◽  
Soil Water Content ◽  
Root Zone ◽  
Potential Evapotranspiration ◽  
Actual Evapotranspiration ◽  
Vegetation Density ◽  
Rainfall Distribution ◽  
Sugar Beets

A model for calculating the daily actual evapotranspiration based on the potential one is presented. The potential evapotranspiration is reduced according to vegetation density, water content in the root zone, and the rainfall distribution. The model is tested by comparing measured (EAm) and calculated (EAc) evapotranspirations from barley, fodder sugar beets, and grass over a four year period. The measured and calculated values agree within 10 %. The model also yields information on soil water content and runoff from the root zone.

scholarly journals PENGARUH TINGKAT PENDIDIKAN, MOTIVASI, DAN KOMPENSASI TERHADAP KINERJA PEGAWAI DI BRI CABANG SEMARANG AHMAD YANI

2019 ◽  
Vol 11 (02) ◽  
pp. 31-47
Author(s):  
Sopi Sopi ◽  
Zumrotun Nafi'ah
Keyword(s):  
Linear Regression ◽  
Multiple Linear Regression ◽  
Industrial Revolution ◽  
Employee Performance ◽  
Science And Technology ◽  
Regression Equations ◽  
Linear Regression Equation ◽  
Improve Performance ◽  
Independent Variables ◽  
Life Education

Education, motivation and compensation are important things that can improve performance. This study aims to explain whether there is an influence of education, motivation and compensation on employee performance. So that through the results of this study it is expected to be a reference for leaders in managing the organization. In this study there are three independent variables namely education, motivation and compensation and one dependent variable is employee performance. At present it is in the era of industrial revolution 4.0, which is marked by; big data / giant data, internet of think, labor knowledge, and long life education. Since the beginning of the life of mankind to an infinite period, it is largely determined by the mastery of science and technology. Science and technology can not be separated from the progress of education level. Education is the base of all changes both individually, as well as countries. Employee performance is determined by the education that is owned, as high as education, the higher the performance and vice versa. The population in this study are BRI CAB employees, SEMARANG A-YANI, 60 people and all of them are sampled. The results of the analysis using SPSS 23 program statistical tools obtained multiple linear regression equation Y = 0.505 X1 + 0.175 X2 + 0.408 X3 The results of multiple linear regression equations show that there is a positive and significant influence between education on employee performance at BRI CAB. A YANI SEMARANG (t count test 6.314> t table 0.05), motivation towards employee performance at BRI CAB. A YANI SEMARANG (tcount 2,160> t table 0,05), and compensation for employee performance at BRI CAB. A YANI SEMARANG (t test 5.108> ttable 0.05). While together (simultaneously) the influence of education, motivation and compensation has an effect on and significant on the performance of employees at BRI CAB. A YANI SEMARANG (count = 44,692> ftabel = 0.05). The influence of the two research variables is very strong with a correlation value of 69.0% for employee performance at BRI CAB. A YANI SEMARANG is influenced by the motivation and compensation education of the remaining 31.0% of the employees' performance at BRI CAB. A YANI SEMARANG is influenced by other variables that affect employee performance.

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