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Implementation of a Surface Water Extent Model using Cloud-Based Remote Sensing - Code and Maps

February 7, 2020

This data release comprises the raster data files and code necessary to perform all analyses presented in the associated publication. The 16 TIF raster data files are classified surface water maps created using the Dynamic Surface Water Extent (DSWE) model implemented in Google Earth Engine using published technical documents. The 16 tiles cover the country of Cambodia, a flood-prone country in Southeast Asia lacking a comprehensive stream gauging network. Each file includes 372 bands. Bands represent surface water for each month from 1988 to 2018, and are stacked from oldest (Band 1 - January 1988) to newest (Band 372 - December 2018). DSWE classifies pixels unobscured by cloud, cloud shadow, or snow into five categories of ground surface inundation; in addition to not-water (class 0) and water (class 1), the DSWE algorithm distinguishes pixels that are less distinctly inundated (class 2: "moderate confidence"), comprise a mixture of vegetation and water (class 3: "potential wetland"), or are of marginal validity (class 4: "water or wetland - low confidence"). Class 9 is applied to classify clouds, shadows and hill shade. Two additional documents accompany the raster image files and XML metadata. The first provides a key representing the general location of each raster file. The second file includes all Google Earth Engine Javascript code, which can be used online ( to replicate the monthly DSWE map time series for Cambodia, or for any other location on Earth. The code block includes comments to explain how each step works.

These data support the following publication: Soulard CE, Walker JJ, Petrakis RE. In review. Implementation of a Surface Water Extent Model in Cambodia using Cloud-Based Remote Sensing. Remote Sensing,

Publication Year 2020
Title Implementation of a Surface Water Extent Model using Cloud-Based Remote Sensing - Code and Maps
DOI 10.5066/P9LH9YYF
Authors Jessica J Walker, Roy E Petrakis, Christopher E Soulard
Product Type Data Release
Record Source USGS Digital Object Identifier Catalog
USGS Organization Western Geographic Science Center - Main Office