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Question about transient land forcing files for CESM-LME

Kamm23

Kelsey
New Member
I'd like to use the CESM-LME transient land forcing files to show how the fraction of US crops and pastures has changed over time, but am not sure what variables to use (e.g., LANDFRAC_PFT, PCT_PFT). I am looking at the files listed in Table 5 on the LME Instructions page (Last Millennium Ensemble Project Insructions).

Any advice would be much appreciated, thanks.
 

Kamm23

Kelsey
New Member
Thank you. I looked over the technical note, but am still a little confused about how to distinguish which surface data variables are influenced by human activity vs non-human activity.

I am looking to use a combination of:
  • PCT_PFT = "percent plant functional type of gridcell"
  • PCT_WETLAND = "percent wetland"
  • PCT_LAKE = "percent lake"
  • PCT_URBAN = "percent urban"
  • HARVEST_VH1 = "harvest from primary forest"
  • HARVEST_VH2 = "harvest from primary non-forest"
  • HARVEST_SH1 = "harvest from secondary mature-forest"
  • HARVEST_SH2 = "harvest from secondary young-forest"
  • HARVEST_SH3 = "harvest from secondary non-forest"
  • GRAZING = "grazing of herbacous pfts"

Ultimately, I am trying to make a figure similar to the one below (This figure is from a preprint of Four-century history of land transformation by humans in the United States: 1630-2020, Xiaoyong Li et. al.), using the CESM-LME transient land forcing files.

Screen Shot 2022-09-21 at 1.45.57 PM.png


Specific Questions:
1) The tech note mentions "grazing areas are assigned to the C3 and C4 grass areas", so the pasture area can be calculated using these two grass types? 2) Is GRAZING referring to domesticated animals only?
3) Is there another document that elaborates on the differences between HARVEST types?
4) Does Crop1 account for both unmanaged and managed crops?



Thank you,
Kelsey
 
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