Alternate Run Modes:Inset Models

Inset Models

GSSHA is able to share data between individual models. The basic process goes like this:

Create the Tier 1 (larger) model
Create the Tier 2 (inset) model
In the Tier 1 model project file, add the XY boundary output cards to refer to the Tier 2 model mask file and output data sets
In the Tier 2 model project file, add the XY boundary input cards to refer to the new data sets from the Tier 1 model
Run the Tier 1 model
Run the Tier 2 model

XY Boundary Output Cards – used in the Tier 1 model:


CARD	Example Parameter
XYBDYOUTPUT_MASK	"..\Tier2Model\Tier2Model.msk"
XYBDYOUTPUT_OVDEP	"..\Tier2Model\Tier1Model.ovdep.ts"
XYBDYOUTPUT_STFLOW	"..\Tier2Model\Tier1Model.sthyd.ts"
XYBDYOUTPUT_GWHEAD	"..\Tier2Model\Tier1Model.gwhead.ts"

XY Boundary Input Cards - used in the Tier 2 model:


CARD	Example Parameter
XYBDYINPUT_OVDEP	"Tier1Model.ovdep.ts"
XYBDYINPUT_STFLOW	"Tier1Model.sthyd.ts"
XYBDYINPUT_GWHEAD	"Tier1Model.gwhead.ts"

The Tier 1 GSSHA simulation will read the Tier 2 mask file and determine where the edges of the Tier 2 model overlap the Tier 1 grid and also where they intersect the Tier 1 stream network. The Tier 1 model will output data for the overland depth (XYBDYOUTPUT_OVDEP), the stream flow (XYBDYOUTPUT_STFLOW), and the groundwater head (XYBDYOUTPUT_GWHEAD) at the edge locations (all Tier 1 cells with Tier 2 edge cells, or nearest Tier 1 stream link/node as it crosses the Tier 2 grid edge) it identified.