Categories: GIS Data

MERIT Hydro: A High-Resolution Global Hydrography GIS Dataset

Scientists have developed MERIT Hydro, a new global map of river systems, with a resolution of 3‐arc sec (90 meters at the equator).  The high-resolution dataset was created with crowdsourced hydrography data from OpenStreetMap as well as water body data (G1WBM, Global Surface Water Occurrence).  This data, coupled with MERIT DEM, was fed into an algorithm that extracted river networks by separating actual inland basins from false depressions caused by errors in the topographic data collected by spacecraft radar systems such as NASA’s Shuttle Radar Topography Mission.

MERIT hydro data mapped for different major rivers of the world. Maps: Dai Yamazaki

The researchers pulled OpenStreetMap data tagged with water related subjects such as “waterway,” “river,” “stream,” “brook,” and “wadi.”  This allowed the algorithm to identify small streams not detectable on Landsat imagery.  It also enabled the researchers to flag man-made hydrological structures such as canals that might be prone to flooding.

Downloading MERIT Hydro

The hydrological dataset, in geoTIFF format, has been made freely available for research and education purposes and can be downloaded from">http://hydro.iis.u‐

The Study

Yamazaki, D., Ikeshima, D., Sosa, J., Bates, P. D., Allen, G., & Pavelsky, T. (2019). MERIT Hydro: A high‐resolution global hydrography map based on latest topography datasets. Water Resources Research.

A More Accurate Global River Map, Eos, July 12, 2019



Published by

Recent Posts

Improving Urban Decision Making with Open Earth Observations

Steven Ramage, Head of External Relations, Group on Earth Observations (GEO), outlines innovative partnerships and…

August 6, 2020

Open Geospatial Data and COVID-19

Some of the key GIS datasets being used today for research and outreach related to…

August 4, 2020

Mapping Urban Heat

Lead by Portland State University professor Vivek Shandas, a network of citizen volunteers and local…

August 3, 2020

Recent Developments in Remote Sensing and Earth Observation

Remote sensing and earth observationcapabilities at satellite, aerial, UAV, and ground levels have radically improved…

August 2, 2020

GIS and the Telecom Market

Devanshu Shrivastava synthesizes an analysis of GIS in the Telecom Market including a growth forecast…

July 29, 2020

Esri Debuts New GIS Tools and Apps at the 2020 Annual User Conference

The first two plenary sessions contained a lot of demonstrations by Esri staff featuring the…

July 22, 2020