cory_pettijohn@oregonstate_edu
New Member
I am running CLM-CN in offline point mode (driven by tower data using Stoeckli et al.'s Modelfarm) on a linux machine here at Oregon State. Currently I am focusing on the semi-arid Metolius Intermediate Ponderosa Pine Ameriflux site (US-ME2) in east-central Oregon.
I am not sure of the best way to spin up the SIMGM groundwater component of the model given the following regional hydrogeological conditions: (1) regional unconfined groundwater depth ~ 75 m below surface in complex volcanic & sedimentary facies; (2) local water well data indicating ~ 3-4 m soil depth, underlain by previously mentioned volcanic materials, including tuff & fractured basalt.
Do I prescribe the initial depth to groundwater before my ~800 yr. spin up for the CN component, or is the point of SIMGM to solve for the depth to this new 'aquifer'? Should I perform a separate hydro. spin-up prior to spinning up CN, considering Niu et al.'s (2007) suggestion of "following the definition of equilibrium described by Yang et al. [1995], the model needs to spin-up for at least 250 years to reach an equilibrium water table depth in arid regions (e.g., Sahara)..." (p. 5, Sec 3.1)? I am just concerned because after my 800 yr+ spin up, the equilibrium depth to groundwater solution = 5.7 m. Maybe I am taking SIMGM's definition of an aquifer too literally???
Thanks so much in advance for any input!
Cheers,
Cory
I am not sure of the best way to spin up the SIMGM groundwater component of the model given the following regional hydrogeological conditions: (1) regional unconfined groundwater depth ~ 75 m below surface in complex volcanic & sedimentary facies; (2) local water well data indicating ~ 3-4 m soil depth, underlain by previously mentioned volcanic materials, including tuff & fractured basalt.
Do I prescribe the initial depth to groundwater before my ~800 yr. spin up for the CN component, or is the point of SIMGM to solve for the depth to this new 'aquifer'? Should I perform a separate hydro. spin-up prior to spinning up CN, considering Niu et al.'s (2007) suggestion of "following the definition of equilibrium described by Yang et al. [1995], the model needs to spin-up for at least 250 years to reach an equilibrium water table depth in arid regions (e.g., Sahara)..." (p. 5, Sec 3.1)? I am just concerned because after my 800 yr+ spin up, the equilibrium depth to groundwater solution = 5.7 m. Maybe I am taking SIMGM's definition of an aquifer too literally???
Thanks so much in advance for any input!
Cheers,
Cory