Can mHM do hourly simulation output?

[9202014710]

Hello. Thank you and your team for developing such a great hydrological model. I am a hydrological engineer from China and I have been using your team's software, mHM, recently.

According to the information on the official website, it seems that mHM can simulate hourly discharge. I have tested it using the sample file (test_domain) and changed the necessary input data from daily to hourly, including pre.nc, pet.nc, tavg.nc, and station.txt (e.g., 00398.txt).

However, even after making the above modifications, the output data is still in daily format. Additionally, I noticed that mHM seems to use the hourly data for daily simulation. I am confused by the result.

I would like to confirm with you whether mHM can be used for hourly simulation and if there is something I have overlooked in my settings.
<mhm-result.png>
Looking forward to your reply.

[9202014710]

test_cs.zip
Here are the modified input files based on the test domain. It appears that I overlooked something, resulting in not obtaining the desired results.

[pallavhydro]

Hi @9202014710

Currently mHM requires you to control sub-daily simulations based on your input gauge data file. The gauge data you have prepared looks good, except for one point.

The line 3 of your data file has n 1 measurements per day, which means you are telling mHM you have one measurement per day, i.e. daily data. You have to change that to n 24 measurements per day since you have hourly data. That should do the trick.

I do accept that this is not clearly communicated in current namelist files and should rather be an option somewhere in mhm.nml. We will work on this point in future.

Let me know if this works for you
Pallav

[9202014710]

Thanks for your response.
It works but the output data still keep daily. My guess is that mHM averaged the hourly data, and the result is still in daily format. I want to get hourly output results, is there anything else need to be modified.

[pallavhydro]

Hi @9202014710

I tested the setup you shared previously where I made single change in your gauge file from n 1 to n 24 in line 3 (my previous suggestion). This worked fine and I got sub daily metrics at runtime screen as well as sub daily gauge simulation files subdaily_discharge.out, subdaily_discharge.nc, in addition to daily_discharge.out, discharge.nc. This should be the case on your end as well (??).

Cheers
Pallav

[9202014710]

Yes, as you said, I got these files. However, the simulation results are still daily, and I want to get hourly simulation flow output results.

[pallavhydro]

Hi @9202014710

Could you please elaborate what you mean by simulation results are still daily?

The way I see, in my previous screenshot, the subdaily_discharge.out file opened on the right half of the editor has hourly simulation values (Qsim_0000000398).

[9202014710]

The result in the picture you posted above is what I want, the output is hourly.
But why isn't the Hour column included in my results (like in my previous figure)? Is it because I haven't adjusted which parameters?

[pallavhydro]

@9202014710

You said that you got the file subdaily_discharge.out in your output folder. Are you sure you are viewing this file? The daily_discahrge.out file will always be created and will be in daily resolution. However, the subdaily_discharge.out file is only created when your observed gauge data has hourly data (and also n = 24 :) ) and is always in hourly resolution.

Let me know if we understood each other this time :)

P

[9202014710]

I see the file subdaily_discharge.out, it's exactly what I want.

Cheers,
Shoudaoz

[pallavhydro]

Hi Shoudaoz @9202014710

Great.

One Request: please mark the response that answered or solved your issue as the answer. That helps to bring a closure to this discussion. This also helps the future visitors of this discussion to spot the solution.

Cheers
P

[9202014710]

According to your statement, I should go check the subdaily_ charge.out instead of daily_discahrge.out, I will check it tomorrow morning when I am working. Thank you.
(I seem to understand now.)