Assessing Accuracy of Vegetation Index Method to Estimate Actual Evapotranspiration

Arturo Reyes-González; Jeppe Kjaersgaard; Todd Trooien; Christopher Hay; Laurent Ahiablame

doi:doi:10.11648/j.earth.20180705.14

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Assessing Accuracy of Vegetation Index Method to Estimate Actual Evapotranspiration

Arturo Reyes-González, Jeppe Kjaersgaard, Todd Trooien, Christopher Hay, Laurent Ahiablame

Published in Earth Sciences (Volume 7, Issue 5)

Received: 15 August 2018 Accepted: 11 September 2018 Published: 11 October 2018

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Abstract

The estimation of actual crop evapotranspiration (ET_a) maps using complex equations and remotely sensed shortwave and thermal infrared imagery can be challenging and may require input data that are not available. There is an opportunity, therefore to create a simpler and faster method to generate ET_a maps using fewer input parameters for situations where limited input data is available or greater uncertainty in the resulting ET estimates are acceptable. We compared the estimates of ET_a produced by a crop coefficient and NDVI-based (K_c-NDVI) method to a full energy balance (EB) method. Clear sky images from Landsat 7 and Landsat 8 were processed and used for the ET_a estimations from maize during two growing seasons in eastern South Dakota, USA. The results showed that the ET_a values from the K_c-NDVI method were lower than the ET_a values from the EB method by 18% for 2015 and 11% for 2016 growing season. During study period the accuracy of ET_a estimation decreased 17% with the K_c-NDVI method. For both years the mean bias error was 0.81 mm day^-1 and the root mean square error (RMSE) was 0.37 mm day^-1. The average daily ET_a of 5.3 mm day^-1. The K_c-NDVI method performed acceptable for ET_a estimations, indicating that this method can be used to estimate ET_a with minimum input parameters at focused regional and field scales for short time periods.

Published in	Earth Sciences (Volume 7, Issue 5)
DOI	10.11648/j.earth.20180705.14
Page(s)	227-235
Creative Commons	This is an Open Access article, distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution and reproduction in any medium or format, provided the original work is properly cited.
Copyright	Copyright © The Author(s), 2018. Published by Science Publishing Group

Keywords

Actual Evapotranspiration, Surface Energy Balance, NDV Crop Coefficient

References

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APA Style

Arturo Reyes-González, Jeppe Kjaersgaard, Todd Trooien, Christopher Hay, Laurent Ahiablame. (2018). Assessing Accuracy of Vegetation Index Method to Estimate Actual Evapotranspiration. Earth Sciences, 7(5), 227-235. https://doi.org/10.11648/j.earth.20180705.14

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ACS Style

Arturo Reyes-González; Jeppe Kjaersgaard; Todd Trooien; Christopher Hay; Laurent Ahiablame. Assessing Accuracy of Vegetation Index Method to Estimate Actual Evapotranspiration. Earth Sci. 2018, 7(5), 227-235. doi: 10.11648/j.earth.20180705.14

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AMA Style

Arturo Reyes-González, Jeppe Kjaersgaard, Todd Trooien, Christopher Hay, Laurent Ahiablame. Assessing Accuracy of Vegetation Index Method to Estimate Actual Evapotranspiration. Earth Sci. 2018;7(5):227-235. doi: 10.11648/j.earth.20180705.14

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@article{10.11648/j.earth.20180705.14,
  author = {Arturo Reyes-González and Jeppe Kjaersgaard and Todd Trooien and Christopher Hay and Laurent Ahiablame},
  title = {Assessing Accuracy of Vegetation Index Method to Estimate Actual Evapotranspiration},
  journal = {Earth Sciences},
  volume = {7},
  number = {5},
  pages = {227-235},
  doi = {10.11648/j.earth.20180705.14},
  url = {https://doi.org/10.11648/j.earth.20180705.14},
  eprint = {https://article.sciencepublishinggroup.com/pdf/10.11648.j.earth.20180705.14},
  abstract = {The estimation of actual crop evapotranspiration (ETa) maps using complex equations and remotely sensed shortwave and thermal infrared imagery can be challenging and may require input data that are not available. There is an opportunity, therefore to create a simpler and faster method to generate ETa maps using fewer input parameters for situations where limited input data is available or greater uncertainty in the resulting ET estimates are acceptable. We compared the estimates of ETa produced by a crop coefficient and NDVI-based (Kc-NDVI) method to a full energy balance (EB) method. Clear sky images from Landsat 7 and Landsat 8 were processed and used for the ETa estimations from maize during two growing seasons in eastern South Dakota, USA. The results showed that the ETa values from the Kc-NDVI method were lower than the ETa values from the EB method by 18% for 2015 and 11% for 2016 growing season. During study period the accuracy of ETa estimation decreased 17% with the Kc-NDVI method. For both years the mean bias error was 0.81 mm day-1 and the root mean square error (RMSE) was 0.37 mm day-1. The average daily ETa of 5.3 mm day-1. The Kc-NDVI method performed acceptable for ETa estimations, indicating that this method can be used to estimate ETa with minimum input parameters at focused regional and field scales for short time periods.},
 year = {2018}
}

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TY  - JOUR
T1  - Assessing Accuracy of Vegetation Index Method to Estimate Actual Evapotranspiration
AU  - Arturo Reyes-González
AU  - Jeppe Kjaersgaard
AU  - Todd Trooien
AU  - Christopher Hay
AU  - Laurent Ahiablame
Y1  - 2018/10/11
PY  - 2018
N1  - https://doi.org/10.11648/j.earth.20180705.14
DO  - 10.11648/j.earth.20180705.14
T2  - Earth Sciences
JF  - Earth Sciences
JO  - Earth Sciences
SP  - 227
EP  - 235
PB  - Science Publishing Group
SN  - 2328-5982
UR  - https://doi.org/10.11648/j.earth.20180705.14
AB  - The estimation of actual crop evapotranspiration (ETa) maps using complex equations and remotely sensed shortwave and thermal infrared imagery can be challenging and may require input data that are not available. There is an opportunity, therefore to create a simpler and faster method to generate ETa maps using fewer input parameters for situations where limited input data is available or greater uncertainty in the resulting ET estimates are acceptable. We compared the estimates of ETa produced by a crop coefficient and NDVI-based (Kc-NDVI) method to a full energy balance (EB) method. Clear sky images from Landsat 7 and Landsat 8 were processed and used for the ETa estimations from maize during two growing seasons in eastern South Dakota, USA. The results showed that the ETa values from the Kc-NDVI method were lower than the ETa values from the EB method by 18% for 2015 and 11% for 2016 growing season. During study period the accuracy of ETa estimation decreased 17% with the Kc-NDVI method. For both years the mean bias error was 0.81 mm day-1 and the root mean square error (RMSE) was 0.37 mm day-1. The average daily ETa of 5.3 mm day-1. The Kc-NDVI method performed acceptable for ETa estimations, indicating that this method can be used to estimate ETa with minimum input parameters at focused regional and field scales for short time periods.
VL  - 7
IS  - 5
ER  -

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Author Information

Arturo Reyes-González

Instituto Nacional de Investigaciones Forestales, Agricolas y Pecuarias (INIFAP), Mexico City, México
Jeppe Kjaersgaard

Minnesota Department of Agriculture, Saint Paul, USA
Todd Trooien

Department of Agricultural and Biosystems Engineering, South Dakota State University, Brookings, USA
Christopher Hay

Iowa Soybean Association, Ankeny, USA
Laurent Ahiablame

University of California ANR, Oakland, USA

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APA Style

Arturo Reyes-González, Jeppe Kjaersgaard, Todd Trooien, Christopher Hay, Laurent Ahiablame. (2018). Assessing Accuracy of Vegetation Index Method to Estimate Actual Evapotranspiration. Earth Sciences, 7(5), 227-235. https://doi.org/10.11648/j.earth.20180705.14

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ACS Style

Arturo Reyes-González; Jeppe Kjaersgaard; Todd Trooien; Christopher Hay; Laurent Ahiablame. Assessing Accuracy of Vegetation Index Method to Estimate Actual Evapotranspiration. Earth Sci. 2018, 7(5), 227-235. doi: 10.11648/j.earth.20180705.14

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AMA Style

Arturo Reyes-González, Jeppe Kjaersgaard, Todd Trooien, Christopher Hay, Laurent Ahiablame. Assessing Accuracy of Vegetation Index Method to Estimate Actual Evapotranspiration. Earth Sci. 2018;7(5):227-235. doi: 10.11648/j.earth.20180705.14

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@article{10.11648/j.earth.20180705.14,
  author = {Arturo Reyes-González and Jeppe Kjaersgaard and Todd Trooien and Christopher Hay and Laurent Ahiablame},
  title = {Assessing Accuracy of Vegetation Index Method to Estimate Actual Evapotranspiration},
  journal = {Earth Sciences},
  volume = {7},
  number = {5},
  pages = {227-235},
  doi = {10.11648/j.earth.20180705.14},
  url = {https://doi.org/10.11648/j.earth.20180705.14},
  eprint = {https://article.sciencepublishinggroup.com/pdf/10.11648.j.earth.20180705.14},
  abstract = {The estimation of actual crop evapotranspiration (ETa) maps using complex equations and remotely sensed shortwave and thermal infrared imagery can be challenging and may require input data that are not available. There is an opportunity, therefore to create a simpler and faster method to generate ETa maps using fewer input parameters for situations where limited input data is available or greater uncertainty in the resulting ET estimates are acceptable. We compared the estimates of ETa produced by a crop coefficient and NDVI-based (Kc-NDVI) method to a full energy balance (EB) method. Clear sky images from Landsat 7 and Landsat 8 were processed and used for the ETa estimations from maize during two growing seasons in eastern South Dakota, USA. The results showed that the ETa values from the Kc-NDVI method were lower than the ETa values from the EB method by 18% for 2015 and 11% for 2016 growing season. During study period the accuracy of ETa estimation decreased 17% with the Kc-NDVI method. For both years the mean bias error was 0.81 mm day-1 and the root mean square error (RMSE) was 0.37 mm day-1. The average daily ETa of 5.3 mm day-1. The Kc-NDVI method performed acceptable for ETa estimations, indicating that this method can be used to estimate ETa with minimum input parameters at focused regional and field scales for short time periods.},
 year = {2018}
}

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TY  - JOUR
T1  - Assessing Accuracy of Vegetation Index Method to Estimate Actual Evapotranspiration
AU  - Arturo Reyes-González
AU  - Jeppe Kjaersgaard
AU  - Todd Trooien
AU  - Christopher Hay
AU  - Laurent Ahiablame
Y1  - 2018/10/11
PY  - 2018
N1  - https://doi.org/10.11648/j.earth.20180705.14
DO  - 10.11648/j.earth.20180705.14
T2  - Earth Sciences
JF  - Earth Sciences
JO  - Earth Sciences
SP  - 227
EP  - 235
PB  - Science Publishing Group
SN  - 2328-5982
UR  - https://doi.org/10.11648/j.earth.20180705.14
AB  - The estimation of actual crop evapotranspiration (ETa) maps using complex equations and remotely sensed shortwave and thermal infrared imagery can be challenging and may require input data that are not available. There is an opportunity, therefore to create a simpler and faster method to generate ETa maps using fewer input parameters for situations where limited input data is available or greater uncertainty in the resulting ET estimates are acceptable. We compared the estimates of ETa produced by a crop coefficient and NDVI-based (Kc-NDVI) method to a full energy balance (EB) method. Clear sky images from Landsat 7 and Landsat 8 were processed and used for the ETa estimations from maize during two growing seasons in eastern South Dakota, USA. The results showed that the ETa values from the Kc-NDVI method were lower than the ETa values from the EB method by 18% for 2015 and 11% for 2016 growing season. During study period the accuracy of ETa estimation decreased 17% with the Kc-NDVI method. For both years the mean bias error was 0.81 mm day-1 and the root mean square error (RMSE) was 0.37 mm day-1. The average daily ETa of 5.3 mm day-1. The Kc-NDVI method performed acceptable for ETa estimations, indicating that this method can be used to estimate ETa with minimum input parameters at focused regional and field scales for short time periods.
VL  - 7
IS  - 5
ER  -

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