Derivation Mathematical Equations for Future Calculation of Potential Evapotranspiration in Iraq, A Review of Application of Thornthwaite Evapotranspiration

2019 ◽  
Vol 60 (5) ◽  
pp. 1037-1048
Author(s):  
Hussein Ilaibi Zamil Al-Sudani
Keyword(s):  
Water Balance ◽  
Potential Evapotranspiration ◽  
Coefficient Of Determination ◽  
Research Review ◽  
Climate Conditions ◽  
Average Temperature ◽  
Mean Temperature ◽  
Mathematical Equations ◽  
Two Parameters ◽  
The Relationship

     In any natural area or water body, evapotranspiration is one of the important outcomes in the water balance equation. As a significant method and depending on monthly average temperature, estimating of potential Evapotranspiration depending on Thornthwaite method was adopted in this research review. Estimate and discuss evapotranspiration by using Thornthwaite method is the main objectives of this research review with considerable details as well as compute potential evapotranspiration based on climatologically data obtained in Iraq. Temperature - evapotranspiration relationship can be estimated between those two parameters to reduce cost and time and facilitate calculation of water balance in lakes, river, and hydrogeological basins. The relationship was obtained using Thornthwaite method in Iraq by dividing the area into seven sectors according to geographic latitude. Each sector has multi meteorological stations where thirty two stations were used with different periods of records. A mathematical relationship was obtained between mean temperature and corrected potential evapotranspiration with (97.45) to (99.84) coefficient of determination. The mean temperature has a decreasing pattern from southern east towards northern west of Iraq affected by Mediterranean Sea climate conditions, while corrected potential evapotranspiration has the opposite direction regarding increased value because of a direct relationship with temperature.

scholarly journals Temperature – Potential Evapotranspiration Relationship in Iraq Using Thornthwaite Method

2019 ◽  
Vol 27 (1) ◽  
pp. 16-25 ◽  
Author(s):  
Hussein Ilaibi Zamil Al-Sudani
Keyword(s):  
Potential Evapotranspiration ◽  
Coefficient Of Determination ◽  
Natural Area ◽  
Mathematical Relationship ◽  
Climate Conditions ◽  
North West ◽  
Mean Temperature ◽  
Crucial Component ◽  
Relationship Of ◽  
The Relationship

One of the most important outcomes in the water balance equation for any natural area or water body is Evapotranspiration and it is also a crucial component of the hydrologic cycle. The relationship of temperature - evapotranspiration was obtained using the Thornthwaite method in Iraq by dividing the area into (7) sectors according to geographic latitude. Each sector has multi meteorological stations where (32) stations were used with different periods of records. A mathematical relationship was obtained between mean temperature and corrected potential evapotranspiration (PEc) with (97.45) to (99.84) coefficient of determination. Mean temperature has a symmetrical decreasing pattern from south-east towards north-west of Iraq affected by Mediterranean Sea climate conditions, while correcting potential evapotranspiration (PEc) has the opposite direction of increasing values due to a direct relationship with temperature.

The importance of an accurate estimation of the radiation balance and interception loss for the evaluation of evapotranspiration

2020 ◽  
Author(s):  
Jitka Kofroňová ◽  
Václav Šípek ◽  
Miroslav Tesař
Keyword(s):  
Water Balance ◽  
Potential Evapotranspiration ◽  
Longwave Radiation ◽  
Surface Characteristics ◽  
Growing Season ◽  
Accurate Estimation ◽  
Radiation Balance ◽  
Climate Conditions ◽  
Interception Loss ◽  
Hbv Model

<p>The accurate estimation of the potential evapotranspiration (PET) is one of the key processes for water balance research and for determination of actual evapotranspiration (AET). The rate of PET is primarily affected by the amount of available water, climate conditions and surface characteristics. One of the main controlling factors is the radiation balance. Both shortwave and longwave radiations significantly influence the rate of PET. Since the longwave radiation is rarely measured, it has been computed. The computing approaches include several coefficients connected to specific climate conditions. The accuracy of original set of coefficients is questionable when applied in different sites. Here we present potential systematic error in estimating PET while using modelled longwave radiation. In our study, the use of original coefficient values in calculated longwave radiation resulted in differences from 20 to 80 mm of PET in the growing season. It decreased to less than 20 mm per season after parameter calibration.</p><p>Interception describes the amount of water captured by vegetation. Captured water often evaporates back to the atmosphere, thus it doesn’t participate in surface runoff or infiltration of water to the soil. Therefore the rate of interception loss hasn’t an impact only on evaporation but also on other components of water balance. As the interception is often neglected, we decided to compare observed and modelled values of interception loss. Five different modelling approaches were selected and discussed against measured values. Resulting interception loss differences were in range from 1 to 60 mm per growing season. The differences in the rate of interception led to overall variations in predictions of discharge, groundwater height and soil moisture content modelled by HBV model.</p>

scholarly journals Phenological Changes of Soybean in Response to Climate Conditions in Frigid Region in China over the Past Decades

2021 ◽  
Author(s):  
Lijuan Gong ◽  
Baoxing Tian ◽  
Yuguang Li ◽  
Shuang Wu
Keyword(s):  
Climate Change ◽  
Global Climate ◽  
Maturity Stage ◽  
Climate Conditions ◽  
Average Temperature ◽  
Mean Temperature ◽  
Sunshine Hours ◽  
Phenological Changes ◽  
Accelerated Growth ◽  
Research And Policy

AbstractPlant phenology becoming a focus of current research worldwide is a sensitive indicator of global climate change. To understand observed soybean phenology and explore its climatic determinants in frigid region (Northeast China and northeast in Inner Mongolia), we studied the phenological changes of soybean [Glycine max (L.) Merr.] for the frigid region during 1981–2017, then analyzed the contribution of major causal climate factors to phenology based on multiple stepwise regression. Altogether, the average temperature from sowing to maturity (WGP) was significant increasing, accumulated precipitation and sunshine hours were decreasing. More than 50% of observations showed delays in sowing, emergence and maturity stage and short durations of sowing to flowering (VGP), flowering to maturity (RGP) and sowing to maturity (WGP). The late sowing was getting the following phenological timing backward, but the flowering and maturity delaying trends were much less than that of sowing timing due to the warming accelerated growth of soybean. Detailed analysis indicated mean temperature and accumulated precipitation of the 1–3 months immediately preceding the mean emergence, flowering and maturity dates influenced the phenological timing in higher latitude areas (HLJ and FL), while in JL and LN, accumulated precipitation and sunshine hours(replacing mean temperature) were the climatic determinants. These results brought light the importance of research and policy to support strategies for adaptation to local condition under the climate change.

scholarly journals The Influence of Evapotranspiration and Wet Deposition on the Variations of PM10 Concentration in the Ciuc Basin

2019 ◽  
Vol 13 (1) ◽  
pp. 33-44
Author(s):  
Réka Boga ◽  
Zsolt Bodor ◽  
Katalin Bodor ◽  
Szende Tonk ◽  
György Deák ◽  
...  
Keyword(s):  
Particulate Matter ◽  
Water Balance ◽  
Negative Correlation ◽  
Wet Deposition ◽  
Potential Evapotranspiration ◽  
Cloud Water ◽  
Average Temperature ◽  
Monthly Average ◽  
Particulate Matter Concentration ◽  
Matter Concentration

Abstract Trend analysis for potential evapotranspiration (PET) and climatic water balance (CWB) is critical in identifying the particulate matter concentration (PM10) variations. The PET is computed based on the monthly average temperature for the Ciuc basin using Thornthwaite parameterization. The highest levels of evapotranspiration appear during the months of May and June. The lowest levels of particulate concentration characterize the period during April-June. Precipitation is highest during May and June. Particulate matter in the highest cloud water is 0.014 µg/m3/mm during April and 0.010 µg/m3/mm during May. One can observe a significant level of negative correlation between particulate matter concentration, the potential evapotranspiration and precipitation.

scholarly journals Interannual fluctuations of the relationship between winter precipitation and air temperature in the heavy-snowfall zone of Japan

2013 ◽  
Vol 54 (62) ◽  
pp. 183-188 ◽  
Author(s):  
Satoru Yamaguchi ◽  
Katsushi Iwamoto ◽  
Sento Nakai
Keyword(s):  
Air Temperature ◽  
Regional Climate ◽  
Winter Precipitation ◽  
The Sea Of Japan ◽  
Climate Conditions ◽  
Multiple Peaks ◽  
Mean Temperature ◽  
Air Temperatures ◽  
Hourly Data ◽  
The Relationship

AbstractRegions of Japan facing the Sea of Japan have some of the world’s deepest seasonal snowpack, although air temperatures averaged over the coldest winter months (January-February) are above 0°C in this mid-altitude zone (35–40˚ N). Therefore, even a slight temperature increase is likely to drastically decrease the snow depth in this area by changing the precipitation form from snow to rain. In this study, to enhance understanding of winter precipitation conditions, we introduce the winter precipitation curve (WPC), which plots the distribution of winter precipitation (December-February) against the corresponding air temperature using hourly data. We then examine the relationship between the WPC and regional climate conditions. The WPC was classified into two types in the study: the single-peak (SP) type, having one sharp peak near 0°C, and the multiple-peaks (MP) type, having several small peaks. Here ‘peak’ indicates that precipitation frequently occurs at a certain temperature. Peaks of the MP type changed position with fluctuations in mean winter temperature, but the peak of the SP type moved only slightly despite annual fluctuations in winter mean temperature. One of the multiple peaks of the MP type appeared at ∼0°C and this peak also remained nearly stationary with fluctuations in winter mean temperature. The peak of the WPC appearing near 0°C in both the SP and MP types likely resulted from the development of the 0°C isothermal layer due to the cooling effect of melting snow particles.

Problematic Internet Use digunakan Ketika Kesepian pada Remaja

2020 ◽  
Vol 14 (1) ◽  
pp. 45-60
Author(s):  
Yashinta Yashinta ◽  
Dwi Hurriyati
Keyword(s):  
Internet Use ◽  
Hypothesis Test ◽  
Problematic Internet Use ◽  
Coefficient Of Determination ◽  
Test Results ◽  
Research Subjects ◽  
Significance Level ◽  
Relationship Of ◽  
The Relationship ◽  
Effective Contribution

This study aims to determine the relationship of loneliness with problematic internet use on boarding students on Silaberanti street in Siantan jaya Opposite Ulu 1 Palembang city. Research subjects numbered 220 people using random sampling methods. Data was collected using a 60 item problematic internet use scale and a 60 item loneliness. Realibility is generated on scale of problematic internet use of 0,955 and loneliness of 0,946.Hypothesis testing uses product moment correlation analysis techniques. Hypothesis test results showed a positive relationshif between loneliness with problematic internet use on boarding students on Silaberanti street in Siantan jaya Opposite Ulu 1 Palembang city r= 0,684 with a significance level of 0,000 (p<0,01). Loneliness in this study made an effective contribution of 46,8% to problematic internet use which can be seen from the coefficient of determination (r²) that is equel to 0,468.

PENGARUH HARGA DAN BRAND TRUST TERHADAP KEPUTUSAN PEMBELIAN OPPO SMARTPHONE (Studi kasus pada OPPO Store, Sinergy Celular Medan)

2019 ◽  
Vol 14 (1) ◽  
pp. 17
Author(s):  
Andi S Tarigan ◽  
Zulkarnaian Siregar
Keyword(s):  
Data Analysis ◽  
Linear Regression ◽  
Multiple Linear Regression ◽  
Coefficient Of Determination ◽  
Purchase Decision ◽  
Brand Trust ◽  
Significance Level ◽  
Research Hypothesis ◽  
Analysis Technique ◽  
The Relationship

AbstrakPenelitian ini bertujuan untuk mengetahui Pengaruh Harga dan Brand Trust Terhadap Keputusan Pembelian pada Sinergy Celular Medan.Sampel dalam penelitian ini adalah seluruh pengunjung Sinergy Celular Medan sebanyak 77 orang.Teknik pengumpulan data yang digunakan adalah melalui kuesioner (angket) yaitu dengan cara menyebarkan kuesioner kepada sampel (responden) dan mengumpulkannya kembali. Teknik analisis data yang digunakan adalah Regresi Linear Berganda.Sebelum data diregresikan maka terlebih dahulu di uji keterkaitannya antara variabel, datanya diuji menggunakan uji normalitas data, multikolinearitas, dan heterokedastisitas.Serta untuk mengetahui kontribusi faktor Harga dan Brand TrustTerhadap Keputusan Pembelian digunakan rumus Koefisien Determinasi (R2). Hipotesis penelitian diterima apabila t hitung >  t tabel dengan tingkat signifikansi 0,1. Nilai t tabel dalam penelitian ini 1,993. Nilai t hitung variabel X1 sebesar 2,107 t hitung lebih besar dari t tabel maka hipotesis di terima, nilai t hitung variabel X2   sebesar 3,405 t hitung lebih besar dari t tabel maka hipotesis di terima. Kata kunci: Harga, Brand Trust, Keputusan Pembelian AbstractThis study aims to determine the Influence of Price and Brand Trust on Purchasing Decision at Sinergy Celular Medan. The sample in this study is all visitors Sinergy Celular Medan as many as 77 people.Data collection technique used is through questionnaire (questionnaire) that is by distributing questionnaires to the sample (respondent) and collect it back. Data analysis technique used is Multiple Linear Regression. Before the data is diregresikan then first in the test the relationship between variables, the data tested using the test of data normality, multicollinearity, and heterokedastisitas. And to know the contribution of price factors and Brand Trust Against Purchase Decision is used the formula Coefficient of Determination (R2). Research hypothesis accepted if t arithmetic> t table with significance level 0,1. The value of t table in this study is 1,993. Value t arithmetic variable X1 of 2.107 t arithmetic greater than t table then the hypothesis received, the value of t arithmetic variable X2 of 3.405 t arithmetic greater than t table then the hypothesis received. Keywords: Price, Brand Trust, Purchase Decision

Development and evaluation of trans-Amadi groundwater parameters: The integration of finite element techniques

2019 ◽  
Author(s):  
Chem Int
Keyword(s):  
Finite Element ◽  
Polynomial Regression ◽  
Nitrate Concentration ◽  
Strong Relationship ◽  
Total Iron ◽  
Coefficient Of Determination ◽  
Port Harcourt ◽  
Polynomial Expression ◽  
The Relationship ◽  
Best Fit

Mathematical model was developed and evaluated to monitor and predict the groundwater characteristics of Trans-amadi region in Port Harcourt City. In this research three major components were considered such as chloride, total iron and nitrate concentration as well as the polynomial expression on the behavious on the concentration of each component was determined in terms of the equation of the best fit as well as the square root of the curve. The relationship between nitrate and distance traveled by Nitrate concentration by the model is given as Pc = 0.003x2 - 0.451x + 14.91with coefficient of determination, R² = 0.947, Chloride given as Pc = 0.000x2 - 0.071x + 2.343, R² = 0.951while that of Total Iron is given as Pc = 2E-05x2 - 0.003x + 0.110, R² = 0.930. All these show a strong relationship as established by Polynomial Regression Model. The finite element techniques are found useful in monitoring, predicting and simulating groundwater characteristics of Trans-amadi as well as the prediction on the variation on the parameters of groundwater with variation in time.

scholarly journals Biomass Burning and Water Balance Dynamics in the Lake Chad Basin in Africa

Earth ◽  
2021 ◽  
Vol 2 (2) ◽  
pp. 340-356
Author(s):  
Forrest W. Black ◽  
Jejung Lee ◽  
Charles M. Ichoku ◽  
Luke Ellison ◽  
Charles K. Gatebe ◽  
...  
Keyword(s):  
Water Balance ◽  
Biomass Burning ◽  
Water Cycle ◽  
Potential Evapotranspiration ◽  
Southern Oscillation ◽  
Wet Season ◽  
Lake Chad ◽  
Chad Basin ◽  
Lake Chad Basin ◽  
Logone Catchment

The present study investigated the effect of biomass burning on the water cycle using a case study of the Chari–Logone Catchment of the Lake Chad Basin (LCB). The Chari–Logone catchment was selected because it supplies over 90% of the water input to the lake, which is the largest basin in central Africa. Two water balance simulations, one considering burning and one without, were compared from the years 2003 to 2011. For a more comprehensive assessment of the effects of burning, albedo change, which has been shown to have a significant impact on a number of environmental factors, was used as a model input for calculating potential evapotranspiration (ET). Analysis of the burning scenario showed that burning grassland, which comprises almost 75% of the total Chari–Logone land cover, causes increased ET and runoff during the dry season (November–March). Recent studies have demonstrated that there is an increasing trend in the LCB of converting shrubland, grassland, and wetlands to cropland. This change from grassland to cropland has the potential to decrease the amount of water available to water bodies during the winter. All vegetative classes in a burning scenario showed a decrease in ET during the wet season. Although a decrease in annual precipitation in global circulation processes such as the El Niño Southern Oscillation would cause droughts and induce wildfires in the Sahel, the present study shows that a decrease in ET by the human-induced burning would cause a severe decrease in precipitation as well.

scholarly journals Quantitative Breast Density in Contrast-Enhanced Mammography

2021 ◽  
Vol 10 (15) ◽  
pp. 3309
Author(s):  
Gisella Gennaro ◽  
Melissa L. Hill ◽  
Elisabetta Bezzon ◽  
Francesca Caumo
Keyword(s):  
Breast Density ◽  
Potential Role ◽  
Multiple Correlation Coefficient ◽  
Low Energy ◽  
Coefficient Of Determination ◽  
Contrast Enhanced ◽  
Increased Risk ◽  
Significant Difference ◽  
Automatic Software ◽  
The Relationship

Contrast-enhanced mammography (CEM) demonstrates a potential role in personalized screening models, in particular for women at increased risk and women with dense breasts. In this study, volumetric breast density (VBD) measured in CEM images was compared with VBD obtained from digital mammography (DM) or tomosynthesis (DBT) images. A total of 150 women who underwent CEM between March 2019 and December 2020, having at least a DM/DBT study performed before/after CEM, were included. Low-energy CEM (LE-CEM) and DM/DBT images were processed with automatic software to obtain the VBD. VBDs from the paired datasets were compared by Wilcoxon tests. A multivariate regression model was applied to analyze the relationship between VBD differences and multiple independent variables certainly or potentially affecting VBD. Median VBD was comparable for LE-CEM and DM/DBT (12.73% vs. 12.39%), not evidencing any statistically significant difference (p = 0.5855). VBD differences between LE-CEM and DM were associated with significant differences of glandular volume, breast thickness, compression force and pressure, contact area, and nipple-to-posterior-edge distance, i.e., variables reflecting differences in breast positioning (coefficient of determination 0.6023; multiple correlation coefficient 0.7761). Volumetric breast density was obtained from low-energy contrast-enhanced spectral mammography and was not significantly different from volumetric breast density measured from standard mammograms.

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