موضوع: Re: Kc for Catchment modeling مرسل: 1/22/2008 شوهد: 28124 times
Re: Kc for Catchment modeling Anna Sikharulidze annano email@example.comJack,
I have read your rticle: WEAP21 – A Demand-, Priority-, and Preference-Driven Water Planning Model, Part II, one of authors of which you are. Here you discuss the caseIn this article the case study of Sacramento River Basin is given. Could you please tell me what Kc-s have you used in this case study for different land types (deciduous, evergreen, shrubs, grass, irrig.pasture) before and after calibration, if you have this data still available. I have problem with one of the catchments I am modeling (Tskenistskali river in Georgia). It seems that I have too much parameters to calibrate and I want to have initial values as best as possible. That's why I am seeking for these kc-s from somewhere. Thanks again. Anna
موضوع: Re: Kc for Catchment modeling مرسل: 1/29/2008 شوهد: 28098 times
Re: Kc for Catchment modeling Samuel Sandoval samuelsandoval firstname.lastname@example.orgDear Anna,
Hi, this is Samuel Sandoval, from the University of Texas at Austin. I haven't done so much about hydrological modeling, I'm more expert in planning model. Althought, Charlotte Amato, Eusebio Ingol, and Daene McKinney have done something in that area, in fact, Eusebio Ingol and Dr. McKiney have done the calibration for the Conchos BAsin, in Mexico, I think it will be great that you take a look to the on-line report they did. This is the link,
If you want more information you can contact Dr. MiKinney or you can send an email directly to Eusebio Ingol, who was the person who calibrate the model. I hope this can help you.
موضوع: Kc for Catchment modeling مرسل: 1/31/2008 شوهد: 28083 times
Kc for Catchment modeling David Yates yates email@example.comAs a first guess, I would recommend setting all Kc's to a value of 1.0. Since we are modeling soil moisture, soil water deficits will reduce ET even with PET is large. I use the Kc value to "tweak" certain crop/land use types... so usually, I have values that range between 0.9 and 1.1 The higher values would be crops that Et above a reference crop value, where the lower values are crops that Et below a reference crop value under non-water limiting conditions. In the case of FAO models, I think Kc's are basically used as a surrogate to soil water deficits, but with the WEAP soil moisture model, we are explicitly modeling those deficits. dy
موضوع: Re: Kc for Catchment modeling مرسل: 9/15/2009 شوهد: 26857 times
Not sure if this will still be useful, but I came across a report that said that the ET of coniferous forests (in the Pacific Northwest of the US) is about 83% that of a reference crop (pasture), so I assume that the Kc would be less than that of the reference crop by about the same amount? For more info, see Black, Spittlehouse, Novack (1989). Estimation of areal evapotranspiration. In Spittlehouse, D.L. eds, Estimating ET from Land Surfaces in BC. IAHS. Publication # 177. p. 245-256.