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Runoff

Mean annual runoff calculated through continuous simulation for the period 1970-1999.

Description

Continuous hydrology simulation was performed using regional pre-calibrated parameters. Batched simulations were run for combinations of land cover, soils, and slopes across the Puget Sound domain.

To allow for parallel computations, a python adaption of HSPF (PyHSPF) developed by David Lambert with funding from the United States Department of Energy, Energy Efficiency & Renewable Energy, Bioenergy Technologies Office (Lampert, 2019) was used to model rainfall-runoff responses. Regional calibration factors for the Puget Lowlands Ecoregion were used as developed by Dinicola (1990) and Clear Creek Solutions (Department of Ecology, 2014).

HSPF calculates discharge for for three flow-paths: surface flow, interflow, and groundwater flow, referred to as SURO, INFW, and AGWO respectively. We report only SURO, INFW, consistent with Ecology Guidance.

More information, including verification of results can be found in the technical reference.

Layer Access in Earth Engine

The javascript commands below can be used to access this layer within the Google Earth Engine Code Editor. A Google Earth Engine account is required.

// Import the layer data dictionary
var data = require('users/stormwaterheatmap/apps:data/public')

// To view data dictionary, print to the console:
print('Data:', data)

//Get this layer from the layer data dictionary:
var layer_name = data.rasters["Runoff"]

Viewing

Individual objects contain all the info used in the stormwater heatmap. To add it to the map, add the layer object.

var display_image = layer_name.layer
Map.addLayer(display_image)

Analysis

To get the raw image data for analysis, access the eeObject key.

var raw_image = layer_name.layer.eeObject
Map.addLayer(raw_image,{},'Runoff')

Visualization

Palette

Colors
eafdfdeafdfd
9cd4da9cd4da
61a8c761a8c7
427bb7427bb7
3f4b963f4b96
292851292851
4061340613

Minimum: 25 mm/year

Maximum: 1016 mm/year

Source

The Nature Conservancy