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Statistical analysis of modified Hargreaves equation for precise estimation of reference evapotranspiration Cover

Statistical analysis of modified Hargreaves equation for precise estimation of reference evapotranspiration

Tellus
Volume 73 (2021): Issue 1
By: ,  ,  ,  ,  ,  ,  ,  ,   and    
Open Access
|Jan 2021
Figures & tables

Figures & Tables

Fig. 1.

Architecture of Fuzzy Logic Interference.

Fig. 2.

Calibration based on fuzzy logic interference.

Table 1.

Criteria used to classify the performance index Values of PI Performance.

Less than 0.4Not GoodBetween 0.41 to 0.55MediumBetween 0.56 to 0.70GoodBetween 0.71 to 0.85Very GoodAbove 0.85Excellent
Table 2.

Empirical Parameters of calibrated Hargreaves-Samani equation.

StationsAhbhchdhBahawalnagar0.00120.5522.80.63Kotli0.00210.4613.60.57Jhelum0.001180.6517.20.64Lahore0.00100.5722.90.67Muzaffarabad0.00130.6215.60.48Sialkot0.00190.5116.20.6Islamabad0.00200.4511.90.61Skardu0.00110.4715.30.74DIK0.00130.6213.80.67Gilgit0.00100.6912.80.55
Table 3.

Comparative analysis of Hargreaves equation, Modified Hargreaves equation with Penman Montieth equation for estimating ETo .

StationEquationMAERMSEPIClassificationBahawalnagarHS179.62187.330.33Not GoodMHS(dh)138.08147.410.51MediumMHS(ah + dh)91.14110.390.61GoodMHS(ah + bh + dh)71.1484.060.73Very GoodMHS(ah + bh + ch + dh)62.469.690.77Very GoodKotliHS140.30147.460.30Not GoodMHS(dh)122.50130.810.51MediumMHS(ah + dh)88.59100.510.59GoodMHS(ah + bh + dh)60.0572.900.68GoodMHS(ah + bh + ch + dh)43.3652.120.81Very GoodJhelumHS164.40171.510.26Not GoodMHS(dh)142.10149.820.51MediumMHS(ah + dh)79.6097.130.63GoodMHS(ah + bh + dh)53.9066.530.78Very GoodMHS(ah + bh + ch + dh)52.5063.830.79Very GoodLahoreHS141.1147.520.34Not GoodMHS(dh)144.7150.180.48MediumMHS(ah + dh)92.01109.360.54MediumMHS(ah + bh + dh)65.6079.740.70GoodMHS(ah + bh + ch + dh)54.563.760.76Very GoodMuzaffarabadHS144.60153.890.42MediumMHS(dh)90.5104.770.58GoodMHS(ah + dh)80.2099.590.63GoodMHS(ah + bh + dh)63.9074.470.75Very GoodMHS(ah + bh + ch + dh)55.8062.300.81Very GoodSialkotHS143.70150.900.36Not GoodMHS(dh)129.70136.770.53MediumMHS(ah + dh)76.9089.660.66GoodMHS(ah + bh + dh)69.0282.570.69GoodMHS(ah + bh + ch + dh)58.271.300.74Very GoodIslamabadHS160.23166.970.34Not GoodMHS(dh)144.12152.420.48MediumMHS(ah + dh)87.07101.060.6GoodMHS(ah + bh + dh)52.5365.770.73Very GoodMHS(ah + bh + ch + dh)47.0253.110.83Very GoodSkarduHS93.24105.720.61GoodMHS(dh)131.16155.960.70GoodMHS(ah + dh)65.4473.820.75Very GoodMHS(ah + bh + dh)53.1760.480.79Very GoodMHS(ah + bh + ch + dh)52.0666.950.87ExcellentDIKHS190.42198.090.3Not GoodMHS(dh)153.66164.090.46MediumMHS(ah + dh)78.6595.240.66GoodMHS(ah + bh + dh)66.4788.640.71Very GoodMHS(ah + bh + ch + dh)58.9867.010.79Very GoodGilgitHS147.15164.340.51MediumMHS(dh)136.3144.570.61GoodMHS(ah + dh)101.64133.360.7GoodMHS(ah + bh + dh)88.7399.450.77Very GoodMHS(ah + bh + ch + dh)54.9465.140.87Excellent
Fig. 3.

ETo estimated by Penman-Monteith, Hargreaves, and four Modified Hargreaves equations. Modified Hargreaves(1), Modified Hargreaves(2), Modified Hargreaves(3), Modified Hargreaves(4) indicates Modified Hargreaves with 1,2,3, and 4 calibrated hargreaves constants respectively.

Fig. 4.

ETo estimated by the Penman-Monteith, Hargreaves, and Modified Hargreaves equations (with four calibrated Hargreaves constants).

Fig. 5.

Change point in historical series of ETo at Jhelum, Bahawalnagar and DIK.

Table 4.

Comparing the results of change point analysis in ETo for various meteorological stations of Pakistan.

StationsPettit’s TestBruishand’s Range TestBruishand’s U TestPYearBr YearBuYearBahawalnagar774419991.5819990.141999DIK626519881.5619880.161988Gilgit612619901.6719950.321995Jhelum405119980.9619980.051998Kotli523719981.2119980.081998Sargodha448219900.9819900.171990Sialkot715120061.2720060.472006Muzaffarabad1160019982.1119981.181998Lahore1849719953.2619953.381995Islamabad518820061.4620060.262006
DOI: https://doi.org/10.1080/16000870.2021.1966869 | Journal eISSN: 3035-9554
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Language: English
Page range: 1966869 - 1966869
Published on: Jan 1, 2021
Published by: Stockholm University Press
In partnership with: Paradigm Publishing Services
Keywords:
ablative,
evapotranspiration,
imprecision,
calibrated,
conventional,
indicators

© 2021 Rimsha Habeeb, Xiang Zhang, Ijaz Hussain, Muhammad Zaffar Hashmi, Elsayed Elsherbini Elashkar, Jameel Ahmad Khader, Sadaf Shamshoddin Soudagar, Alaa Mohamd Shoukry, Zulfiqar Ali, Fares Fawzi Al-Deek, published by Stockholm University Press
This work is licensed under the Creative Commons Attribution 4.0 License.

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