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The hydrologic influence is just the accumulated terrain and climate wetness variables. Hydrologic influence is a Teren Inc. developed derivative created in a two-phase approach and represents the influence of local hydrology on the surrounding area determined using the results from a dynamic flow network and determining the least vertical and horizontal differences between each digital elevation model cell and its nearest stream cell. The flow network is created, using a 10-meter DEM, by dynamically calculating stream initiation and potential moisture states as a function of a terrain wetness weight. This weight is a function of precipitation weighted by terrain curvature, slope, and solar incidence. This weight is accumulated downslope along with total accumulated area. These are used to calculate stream initiation and total flow accumulation is calculated to determine the artificial flow network. The flow network is a source point of moisture from which local terrain and climate, Euclidean distance from, and slope are examined. The overall hydrologic influence of a source point of moisture on the surrounding area is based on these inputs. This determines the first phase of the hydrologic influence. Phase two determines network and hillslope processes. A derivation of a flow accumulation model where the outflow from each grid cell is proportioned between up to two downslope grid cells, thus divergent flow paths are possible. Flow that originates at a particular grid cell may enter the stream at different cells. A novel facet of this model is that accumulation can transition between growing or decaying as slope flattens or steepens and as the network passes through different precipitation regimes. These two-phase outputs create the Hydrologic Influence covariate.
Purpose: The purpose of the hydrologic influence is to weight the hydrology and depressions models based on the accumulated area of weighted with evapotranspiration weighted 30 year average precipitation derived from PRISM (1992-2022).
Creation Date: 20240607
Publication Date: 20240607
Revision Date:
Refresh Cycle: Updated periodically as new imagery becomes available
Version: 1.0.0
Change Log: Service deployed.
The hydrologic influence is just the accumulated terrain and climate wetness variables. Hydrologic influence is a Teren Inc. developed derivative created in a two-phase approach and represents the influence of local hydrology on the surrounding area determined using the results from a dynamic flow network and determining the least vertical and horizontal differences between each digital elevation model cell and its nearest stream cell. The flow network is created, using a 10-meter DEM, by dynamically calculating stream initiation and potential moisture states as a function of a terrain wetness weight. This weight is a function of precipitation weighted by terrain curvature, slope, and solar incidence. This weight is accumulated downslope along with total accumulated area. These are used to calculate stream initiation and total flow accumulation is calculated to determine the artificial flow network. The flow network is a source point of moisture from which local terrain and climate, Euclidean distance from, and slope are examined. The overall hydrologic influence of a source point of moisture on the surrounding area is based on these inputs. This determines the first phase of the hydrologic influence. Phase two determines network and hillslope processes. A derivation of a flow accumulation model where the outflow from each grid cell is proportioned between up to two downslope grid cells, thus divergent flow paths are possible. Flow that originates at a particular grid cell may enter the stream at different cells. A novel facet of this model is that accumulation can transition between growing or decaying as slope flattens or steepens and as the network passes through different precipitation regimes. These two-phase outputs create the Hydrologic Influence covariate.
Purpose: The purpose of the hydrologic influence is to weight the hydrology and depressions models based on the accumulated area of weighted with evapotranspiration weighted 30 year average precipitation derived from PRISM (1992-2022).
Creation Date: 20240607
Publication Date: 20240607
Revision Date:
Refresh Cycle: Updated periodically as new imagery becomes available
Version: 1.0.0
Change Log: Service deployed.