User:Cmadsen/GSSHA Permafrost

Permafrost

This allows the simulation of permafrost in areas where applicable. The option can be turned on in Job Control and parameters edited there. It is also available in GSSHA Map Table Editor

Job Control

• Permafrost – Turn on to allow use editing of parameters in GSSHA Map Tables

GSSHA Permafrost Options

• Parameter –
  • Permafrost time step – Turn on if needed. When turned on, Value can be edited.
• Value – Only editable if Permafrost time step is turned on. Decimal number.
• Units – Time step units in seconds.

GSSHA Map Tables

The following options are available on this tab:

• Using index map – A drop-down listing all available index maps in the project. Select the desired index map from the list.
• Index map type – A drop-down list of index map types in the project. Select the desired type.
• Generate IDs – Generates a list of IDs from those found in the selected index map.
• Add ID – Adds a new ID to the spreadsheet, allowing manual creation of a new ID.
• Delete ID – Immediately deletes the selected ID.

The spreadsheet displays all of the IDs in the selected index map, one per column. It has the following rows:

• ID – A unique type ID.
• Description1 – An alphanumeric field. Enter a concise descriptive name for the ID type.
• Description2 – An optional alphanumeric field. Enter additional concise descriptive information.
• Initial temperature plot – The initial temperature conditions
  • Define – Brings up the XY Series Editor dialog.
• Computational node depths – Shows the depths for the computational nodal points.
  • Define – Brings up the XY Series Editor dialog.
• Thickness of soil layer (m) – Defines, in meters, how thick the soil layer is.
• Phase change temperature (C) – The temperature at which transformation from solid to liquid occurs.
• Volumetric soil water content – Volume of liquid water per volume of soil. Fraction of 1
• Volume of unfrozen water – Amount of unfrozen water in the soil in subzero temperatures. Fraction of 1
• Unfrozen water parameter "A" – Decimal number.
• Unfrozen water parameter "B" – Decimal number. (May be negative)
• Unfrozen water parameter "C" – Decimal number.
• Thawed soil thermal conductivity – The ability for the thawed soil to conduct heat. W m⁻¹ k⁻¹
• Frozen soil thermal conductivity – The ability for the frozen soil to conduct heat. W m⁻¹ k⁻¹
• Volumetric heat capacity – The amount of heat it takes to raise the temperature by one degree Celsius. J m⁻¹ m⁻¹ m⁻¹ k⁻¹

Properties

• Permafrost output – toggle on/off
• Permafrost output depths – Clicking brings up the XY Series Editor dialog
• Permafrost map table ID –

Permafrost output

Several types of output can be available if the appropriate options have been turned on. These include hydrographs, temperatures output and summary files.