Hi everyone, I’m Nicole. I´m running SWY Model and I encountered some issues preparing the inputs and obtaining the results.
I used all the default parameters (TFL=1000, beta and gamma=1, alpha=1/12)
I didn’t use local recharge, so I uploded the directories with monthly precipitation and evapotranspiration maps. The soil map has some missing data in the water body zones. What would correspond in these cases?
Finally, I uploaded the rain events table (not climate zones).
I’ve checked the inputs and they seem correct. The only thing missing are those values without data in the soil map. Could that be the only problem? The model runs correctly without errors, but the results don’t seem valid.
The only results that I think are consistent are those of QF (ranging from 0 to 1914), although there is missing data for the water bodies (I assume due to the lack of information on the soil map), and those of L and L_avail (both ranging from -1841 to 1274, I don’t know if it’s correct to have negative values and for them to be equal).
The rest of the results have a lot of missing data (no data), especially in the streams areas, namely: L_sum (-704660 to 8817541) and L_sum_avail (-000018 to 25822), B (0 to 1274), and B_sum (-704660 to 8817).
Finally, Vri has no data values (-3.40282e+38 to ±3.40282e+38), and in the data aggregated by sub-basins (there are 3), “nan” appears for qb and “0” for Vri_sum.
It would be very helpful if you could guide me on any errors I might be making. I remain available for any other information that may be useful.
Hi!
I’ve buffered all inputs except the DEM and filled in the missing values, so now it’s running and returning all the results. However, I’m not sure the range is correct. Could you help me with this?
P: 929 to 1478
B: 0 to 937
B_sum: -28 to 29
L_avail: -1807 to 937
L: -1807 to 937
L_sum_avail: -0.000021 to 24776
L_sum: -28 to 29
QF: 0 to 1964
Vri: -0 to 0.000001
aggregated_results: subbasins 1, 2, and 3
qb: 1=65; 2=90; 3=3.5
vri_sum: 1=0.43; 2=0.54; 3=0.013
The soil map has some missing data in the water body zones. What would correspond in these cases?
This isn’t a perfect solution, but I would recommend interpolating to fill in the missing soil values. Here is an old post that mentions this issue.
The only results that I think are consistent are those of QF (ranging from 0 to 1914), although there is missing data for the water bodies (I assume due to the lack of information on the soil map)
Yes, you are correct that you will see missing data in the QF layer where there are missing soil data.
and those of L and L_avail (both ranging from -1841 to 1274, I don’t know if it’s correct to have negative values and for them to be equal).
Yes, L can be negative. Here is a section of the users guide that discusses this:
“The localrecharge, or potential contribution to baseflow, of a pixel is computed from the local water balance. Precipitation that does not run off as quickflow, and is not evapotranspired by the vegetation on a pixel, can infiltrate the soil to become local recharge. Local recharge can be negative if a pixel does not receive enough of its own water to satisfy its vegetation requirements (determined by its crop factor Kc ), so it uses water generated upslope of the pixel as well (referred to as an “upslope subsidy”.)”
Does this address your concerns? If not, what results are you expecting to see? If you feel like the results you’re getting are incorrect, please first ensure that you’re running the latest version of InVEST (as updates to the SWY model have been made in recent releases) and if you’re still concerned, feel free to share your data and logfile and I can take a closer look. Thanks!
Hi @csimpson!
Thank you so much for your answer. In a later comment, I mentioned that I was able to obtain the full results by buffering the inputs and filling in the no data values. I think the results make a lot of sense, given your clarification about L. If I have any other questions, I’ll get in touch, but I think this will be very helpful! Thanks again.
In that case, nan pixel values on the edges of the precip rasters were propagating through to the results. That might explain why buffering the inputs and filling in nodata values resolved the problem.
Also, we fixed the bug with nan values being used in the math, that fix was released in version 3.14.3.
Which version of invest are you using @nicole.pommares ? Please always upload your logfile when posting about a model run, it can tell us the version, and other useful info. Thanks.
Hi, Dave
I’m using version 3.14.2. Thanks for the clarification about the bug fix! I think I will update my InVEST version.
If I have any further questions, I’ll make sure to include the logfile as you suggested. Thanks!
Nicole