WRF Noah-MP Dynamic vegetation

Hello,

I am simulating one year with drought by WRF Noah-MP. When I set dveg=2(dynamic vegetation), I got even larger LAI values than dveg=1(LAI from a table), which is really confusing as the vegetation might be dying for a long drought. Then I have a check of the results and found, for the scenario with dveg=2, the LAI values seemly become larger and larger with time, while when dveg=1, the LAI values seemly didn't become larger and looks normal. The WRF version I used is 3.9.1, and I also tried by version 4.0, but same problem occurred. I run the model for one month every time. The namelist.input is attached.

Anyone could give some advice? Thanks so much in advance!

Cancan

Hi Cancan,
I tested this with a simple case I have, but am unable to repeat the problem. Are you seeing this increase in a single location, or is throughout the entire domain? How long do you have to run to see the increasing LAI? Is it with every output time? Do you mind sending a couple of your wrfout* files so that I can take a look at this? If you are unable to upload due to size restrictions, see the cover page of this forum for details regarding uploading large files. Thanks!

Hi Kwerner,

Thank you so much for your reply as I am strugling with this problem for quite long time. I calculated the daily averaged LAI value in my study area (so the mean values throughout the entire domain )and the daily mean LAI with dynamic scenario (dveg = 2)is incresing. I have run around 10days (one month before, but for a faster test, 10days now).
I have uploaded several wrfout* files to Nextcloud, named wrfout_files_Cancan.It would be nice if you could have a look.
Beside, I have changed a little of the namelist.input (add sst_update, rdlai2d,etc )and the updated one is attached, but the problem still occurred.
When running WPS program, the land use categories I used is MODIS; When USGS is used, the situation is better, and LAI values didn't increase anymore, or sometimes started to increase after around a week. So I am really confused about this. I wonder when NoahMP is used, is the land use catefories of MODIS or USGS a problem?

Thank you again for your kind help!!

Hi,
1) Is there a reason why you must use MODIS, instead of USGS? If not, since you are seeing more realistic results with USGS, perhaps you should use that.
2) If option 1) doesn't work for you, will you please re-send the wrfout* files, packaged as a *.tar file? Unfortunately we are unable to open .rar files. I apologize for the inconvenience.

Hi Kwerner,

I need to compare the simulations when USGS and MODIS data used,so the problem need to be figured out.I upload the wrf files (packaged as *tar,named as modis_cancan_0807) again,please have a try if you can download.

BTW，I wonder about the spin up time. If I want to run one month for the LAI changes, how long about the spin up time ?

Thank you very much for your help!

Hi,
I apologize for the long delay. It seems this inquiry got overlooked in my inbox. Are you still having problems with this, or have you resolved the issue?

As far as I know, the dynamic vegetation option in NoahMP never really works. The developer simply lost interests to debug/further develop this option.

Hi,

Following up on this issue, I'm currently using WRF v4.2.2 and for my current simulation I'm using the CONUS physics suit and NOAH-MP dynamic vegetation (option 2). my WRF output for the whole month has a constant value for LAI and vegetation fractions. So, I just need to confirm that, Is it due to a faulty NOAH-MP dynamic vegetation integration in WRF or an incompatibility issue with a physics option? Did the mentioned issue with development got resolved in this issue or should I avoid using the dynamic vegetation option?
And what about the other NOAH-MP dynamic vegetation options (e.g. option 4, 7, or 10)?

Thanks,
Mahmoud

This is because the inconsistency in your nameless options, Dynamic vegetation is only available for NoahMP, whereas CONSU suite actives Noah.