From csdms
[edit] Lake-Permafrost with Subsidence
Contents |
[edit] Metadata
| Modeler information | |
|---|---|
| First name | Nora |
| Last name | Matell |
| Type of contact | Model developer |
| Institute / Organization | INSTAAR, University of Colorado |
| Postal address 1 | 450 UCB |
| Postal address 2 | |
| Town / City | Boulder |
| Postal code | 80305 |
| State | Colorado |
| Country | USA |
| Email address | nlmatell@gmail.com |
| Phone | |
| Fax | |
| Model identity | |
|---|---|
| Model type | Single |
| Spatial dimensions | 1D |
| Spatial extent | |
| Model domain | |
| One-line model description | 1-D lake-permafrost thermal model with subsidence. |
| Extended model description | Models temperature of 1-D lake-permafrost system through time, given input surface temperature and solar radiation. Model is fully implicit control volume scheme, and cell size can vary with depth. Thermal conductivity and specific heat capacity are dependent on cell substrate (% soil and % ice) and temperature using the apparent heat capacity scheme where freezing/thawing occurs over a finite temperature range and constants are modified to account for latent heat. Lake freezes and thaws depending on temperature; when no ice is present lake is fully mixed and can absorb solar radiation. Upper 10 m substrate contains excess ice and, if thawed, can subside by this amount (lake then deepens by amount of subsidence). "Cell type" controls whether cell has excess ice, only pore space ice, or is lake water. |
| Model technical information | |
|---|---|
| Supported platforms | Windows |
| Other platform | |
| Programming language | Matlab |
| Other program language | |
| Code optimized | Single Processor |
| Start year development | 2008 |
| Does model development still take place? | No |
| If above answer is no, provide end year model development | 2009 |
| Model availability | As code |
| Source code availability (Or provide future intension) | Through owner |
| Source web address | |
| Program license type | GPL v2 |
| Program license type other | |
| OpenMI compliant | No but possible |
| CCA component | No but possible |
| IRF interface | No but possible |
| Memory requirements | -- |
| Typical run time | -- |
| Input - Output description | |
|---|---|
| Describe input parameters | Daily average solar radiation for location (at surface). |
| Input format | |
| Other input format | Matlab .mat file |
| Describe output parameters | Matlab variables, Matlab graphs |
| Output format | |
| Other output format | Matlab variables, Matlab graphs |
| Pre-processing software needed? | No |
| Describe pre-processing software | |
| Post-processing software needed? | No |
| Describe post-processing software | |
| Visualization software needed? | No |
| If above answer is yes | |
| Other visualization software | |
| Process description model | |
|---|---|
| Describe processes represented by the model | Heat conduction in permafrost, lake ice growth-decay, permafrost subsidence due to excess ice |
| Describe key physical parameters and equations | Heat conduction equations, lake ice growth-decay equations |
| Describe length scale and resolution constraints | Near surface, length scale should be 5-10 cm if subsidence occurring. Deeper in permafrost, 1+ m okay. |
| Describe time scale and resolution constraints | Model needs daily (or smaller) timesteps. |
| Describe any numerical limitations and issues | Runs slowly - iterates implicit scheme. Some sort of matrix algebra might improve speed. |
| Model testing | |
|---|---|
| Describe available calibration data sets | -- |
| Upload calibration data sets if available: | |
| Describe available test data sets | Permafrost model can be tested with ground temperature time series at several depths. Lake model can be tested with known ice depths (though snow, not accounted for in model, can affect depth by several 10s of cm). |
| Upload test data sets if available: | |
| Describe ideal data for testing | Lake temperature time series, known lake depth, underlying permafrost time series. Surface temperature time series as input (not air temperature). |
| Users groups model | |
|---|---|
| Do you have current or future plans for collaborating with other researchers? | -- |
| Documentation model | |
|---|---|
| Provide key papers on model if any | Model based on previous models by Ling and Zhang (2004), Plug and West (2008), Liston and Hall (1995). Model described in Matell et al. (in preparation) and Matell (2009, masters thesis). |
| Is there a manual available? | No |
| Upload manual if available: | |
| Model website if any | |
| Model forum / discussion board | |
| Additional comments | |
|---|---|
| Comments | |
