negative channel storage values

[aschoen]

Hello, I am new to raven. I set up a small basin (~10 km2) as a single basin using the UBCWM template for processes.

I have the following settings in the .rvi:
:Routing ROUTE_NONE
:CatchmentRoute ROUTE_TRI_CONVOLUTION

And in the hru.rvh
:SubBasins
:Attributes, NAME, DOWNSTREAM_ID, PROFILE, REACH_LENGTH, GAUGED
:Units, none, none, none, km, none
1, sub1, -1, default_trap, _AUTO, 1
:EndSubBasins

I am getting a -25% to -35% bias in the modelled streamflow. When I check the precipitation (4.4 mm) to the observed streamflow (4.0 mm) the R/P looks good (0.91), ample water to produce enough streamflow. So where is the water going? I notice that there are large negative values in the Channel Storage (mm) in the WatershedStorage.csv file (-2.99015 mm). Is this a sign that something is not set up properly? I see negative Channel Storage in the Alouette tutorial, but they are smaller -0.21407.

Thanks for any help you can provide.

Arelia

[jrcraig]

Hi Arelia,

Apologies for the late reply. Channel storage is only used as a diagnostic variable, and is not a state variable in the model. It is by default initialized to zero at the start of the simulation. Because of this, -3mm of storage is *relative* to an initial (unknown) storage in the channel.

Net impact - this is not a concern, and could be alleviated by initializing the channel storage to a more realistic value in the .rvc file.