order of PFT types in CLM3.0 PFT dataset

[shalder3@gmu_edu]

Dear Sir/Madam,

I have used the high resolution land surface pft data "mksrf_pft.nc" meant for CAM 3.0 for my regional climate model simulations using RegCM4.0, that has clm3.5 as a land surface model. This dataset is available from: http://www.cesm.ucar.edu/models/atm-cam/download/

From the CLM technical manual the order of the PFTs in this high resolution data seem to be the following:

! 1 => needleleaf evergreen temperate tree
! 2 => needleleaf evergreen boreal tree
! 3 => needleleaf deciduous boreal tree
! 4 => broadleaf evergreen tropical tree
! 5 => broadleaf evergreen temperate tree
! 6 => broadleaf deciduous tropical tree
! 7 => broadleaf deciduous temperate tree
! 8 => broadleaf deciduous boreal tree
! 9 => broadleaf evergreen shrub
! 10 => broadleaf deciduous temperate shrub
! 11 => broadleaf deciduous boreal shrub
! 12 => c3 arctic grass
! 13 => c3 non-arctic grass
! 14 => c4 grass
! 15 => corn
! 16 => wheat

The 17th category is non-vegetated. However, if I just plot the first pft (PFT 1) in mksrf_pft using GrADS, the vegetation cover over the South Asian region, particularly the deserts and dry areas, don't suggest that it could be needleleaf evergreen temperate tree. This pft 1 category in mksrf_pft.nc has high percentage coverage over the dry regions. This means, the PFTs are not necessarily in the same order in the file as shown above.

I would like to know what is the actual order of the PFTs in the file? Secondly, which PFT category could be called bare ground?

Thanks and regards,
Subhadeep.

 

[yfan1@uni-goettingen_de]

Hi Subhadeep,I don't know about CLM3.0 but for CLM4.0/4.5 you need to shift the PFT index (i.e. "pftnum") down by 1, e.g.  0  1  2  3  4  5  6  7  8  9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24.....The first item in the PFT list is "not_vegetated (pftnum=0)" or bare ground. the second item (pftnum=1) is "needleleaf_evergreen_temperate_tree" and so on. I don't think the 17th caterory is non-vegetated because there are more than 17 PFTs in CLM4.0/4.5.Best regards,Yuanchao

 

[shalder3@gmu_edu]

Hi Yuanchao,Thanks for the reply. There are 17 pft categories in CLM3.0/CLM3.5, so I will have to deal with those. I will shift the pft's by 1 place now.However, if I plot the second item (pft_num=1), it shows too much needleleaf temperate evergreen tree over the drier regions. I don't think that is correct. What would be the correct order of the pft's then? In order to verify, you may also check the global file from the link: http://www.cesm.ucar.edu/models/atm-cam/download/