Developing an Evapotranspiration Model

This problem will familiarize the user with selected features of the OMS interface.

It uses two existing potential evapotranspiration(PET) components to build a simple PET model. One possible application of OMS is to evaluate alternative concep­tualizations of selected physical processes. In this example we will evaluate the Hamon and Modified Jensen-Haise methods for computing PET.

Tutorial Steps

The steps to accomplish in this exercise are:

• Create a new OMS project.
• Create a new OMS model.
• Run the new model.
• Display and analyze model results.

Advanced topics

• Creating a FORTRAN component
• Modify model parameters to obtain agreement between the Hamon and Jensen-Haise simulated POTET.

References

• Federer, Anthony C., and Lash, Douglas, 1978, Brook: A hydrologic simulation model for eastern forests: Durham, New Hampshire, University of New Hampshire, Water Resources Research Center, Research Report No. 19, 84 p.

• Hamon, W. R., 1961, Estimating potential evapotranspiration: Proceedings of the American Society of Civil Engineers, Journal of the Hydraulic Division, vol. 87, no. HY3, p.107-120.

• Jensen, M. E., and Haise, H. R., 1963,Estimating evapotranspiration from solar radiation: Proceedings of the American Society of Civil Engineers, Journal of Irrigation and Drainage, v.89, no. IR4, p. 15-41.

• Jensen, M. Rob, D. C. N., and Franzoy, C. E., 1969, Scheduling irrigations using climate-crop-soil data NationalConference on Water Resources Engineering of the American Society of Civil Engineers, New Orleans, LA., 1969, Proceedings, 20 p.

• Murray, F. W., 1967, On the computation of saturation vapor pressure: Journal of Applied Meteorology, v. 6, p.203-204.