NSink Rasterific

author: Jeff Hollister date: 11/14/13

Based on my understanding of the current NSink tool, the information we would like out of it is the following:

Total Potential Reduction Map: The Delivery Map

Weighted FlowLength - FlowLength should be close. Just need to figure out how the weighting works.

Flow path from a given location

Cost Path: Inputs are grid with source and destination. Plus a backlink grid. The backlink grid is simply flow direction from the elevation. Cost surface is a constant. I used the “Best_Single” path type. It should work (haven't tested this) for multiple end points (i.e as in coastal watersheds) and would pick the shortest one.

Only two geoprocessing services required. One, get the starting point and two, calculate the flow path with Cost Path.

So, for instance:

Here's an image of starting elevation:

smallElev

Next a possible starting point on the landscape:

smallElevSource1

And the resulting flow path from that point:

smallElevPath1

A second starting point:

smallElevSource2

And a second flow path:

smallElevPath2

Landcover along the flowpath

Take flow path, calculate Euclidean distance from that flow path, select cells greater than buffer distance and turn to NA. Mask out landcover. Count cells of each class, multiply by 900.

Static Map of important locations for reductions (aka: The Walter)

Need to think more about this, but it is some combination of Flow Accumulation and sinks.