Contents
How is flow accumulation calculated in ArcGIS help?
An optional input raster for applying a weight to each cell. If no weight raster is specified, a default weight of 1 will be applied to each cell. For each cell in the output raster, the result will be the number of cells that flow into it. The output accumulation raster can be integer or floating point type.
What do output cells with high flow accumulation do?
Output cells with a high flow accumulation are areas of concentrated flow and can be used to identify stream channels. Output cells with a flow accumulation of zero are local topographic highs and can be used to identify ridges.
How are the results of flow accumulation used?
The results of Flow Accumulation can be used to create a stream network by applying a threshold value to select cells with a high accumulated flow. For example, the procedure to create a raster where the value 1 represents the stream network on a background of NoData could use one of the following:
Which is the output raster for flow accumulation?
INTEGER — The output raster will be integer type. The output raster that shows the accumulated flow to each cell. This example creates a raster of accumulated flow into each cell of an input flow direction Grid raster. This example creates a raster of accumulated flow into each cell of an input flow direction IMG raster.
Which is the default weight for flow accumulation?
An optional input raster for applying a weight to each cell. If no weight raster is specified, a default weight of 1 will be applied to each cell. For each cell in the output raster, the result will be the number of cells that flow into it. The output accumulation raster can be integer, floating point, or double type.
How is input flow direction created in ArcGIS?
Input flow direction can be created using the D8, Multiple Flow Direction (MFD) or D-Infinity (DINF) methods. The type of input flow direction raster between these three influences how the Flow Accumulation tool partitions and accumulates flow in each cell.
What is the result of flow accumulation in rasteranalysis?
The result of Flow Accumulation is a raster of accumulated flow to each cell, as determined by accumulating the weight for all cells that flow into each downslope cell. The Flow Accumulation tool supports three flow modeling algorithms while computing accumulated flow.