hydroET

An R package related to evapotranspiration research.

Installation

You can install the hydroET from github:

remotes::install_github('cug-xyx/hydroET')

PET / ET models

Function name	Model name	Status	Language
ET_CR_Ma	Calibration-free complementary relationship (CR) model	❌	R
PET_Penman1948	Penman 1948 model	✅	cpp
PET_PT1972	Priestley-Taylor model	✅	cpp
PET_Yang2019	Maximum evaporation model	✅	cpp
PET_Zhou2024	Energy-based PET (PETe)	✅	cpp
ET_summary	A data.frame containing various types of evapotranspiration results	❌

Attribution Framework

• Elasticity Coefficient Method (ECM)

TODO

• Accuracy of inverse function to derive TwsandTwb
• Calibration of alpha (Appendix B in Ma and Szilagyi, 2019)
• Check ET_CR_Ma and ET_CR_Ma_ref, which one is the correct algorithm
• Develop convenient functions to directly download ET/PET forcing data on GEE
  • site scale
  • grid scale
• Maximum Evaporation Theory (Yuting Yang, Zhuoyi Tu)
• PET algorithm developed by Zhou & Yu (2024)
• Develop cpp version functions
• Update doc
• Using use method to process SpatRaster object
• Add references in doc
• Deploy gh-pages

References

• Ma, Ning, Jozsef Szilagyi, and Yongqiang Zhang. “Calibration‐Free Complementary Relationship Estimates Terrestrial Evapotranspiration Globally.” Water Resources Research 57, no. 9 (2021). https://doi.org/10.1029/2021WR029691.
• Tu, Zhuoyi, and Yuting Yang. “On the Estimation of Potential Evaporation Under Wet and Dry Conditions.” Water Resources Research 58, no. 4 (2022). https://doi.org/10.1029/2021WR031486.
• Zhou, Sha, and Bofu Yu. “Physical Basis of the Potential Evapotranspiration and Its Estimation over Land.” Journal of Hydrology 641 (September 2024): 131825. https://doi.org/10.1016/j.jhydrol.2024.131825.
• Zhou, Sha, and Bofu Yu. “Neglecting Land–Atmosphere Feedbacks Overestimates Climate-Driven Increases in Evapotranspiration.” Nature Climate Change, 1–8 (September 11, 2025). https://doi.org/10.1038/s41558-025-02428-5.