Global Rivers Group
@Texas A&M

We use satellites, models, and fieldwork to study Earth's inland waters


We're an academic research group in the Department of Geography at Texas A&M University. Founded in 2018 by Dr. George H. Allen, we are recruiting students and postdocs who are interested in using emerging technology to solve problems involving freshwater resources. 

What we do

We study freshwater resources using remote sensing, fieldwork, and models. We seek to understand how climate change and land use are altering the global water cycle, in particular river and lake hydrology. With rapid advancements in satellite technology, computing power, and model sophistication, it is an exciting time to be studying the global water cycle.


Why we do it

Water is widely considered to be the world’s most vital natural resource, yet freshwater systems are directly endangered by human activities. Our work is motivated by a desire to promote the conservation, management, and understanding of Earth's surface water resources.



Updated May 3, 2022

Apr 25, 2022—Paper published in Nature Sustainability entitled "Assessing placement bias of the global river gauge network", which identifies which river environments are systematically undermonitored by the global gauge network. George co-led this project with NSF Dry River RCN members, Corey Krabbenhoft (University at Buffalo) and Julian Olden (University of Washington). Global Rivers Group alumni Catherin Franklin also conducted analysis for the study and coauthored the paper: and a news article covering the study. 


Apr 21, 2022Paper led by Jida Wang at Kansas State University published in Earth Systems Science Data entitled, "GeoDAR: georeferenced global dams and reservoirs dataset for bridging attributes and geolocations". This work geolocates much of the ICOLD World Register for Dams database:

Mar 7, 2022—Paper published in Proceedings of the National Academy of Sciences (PNAS) entitled "The importance of hydrology in routing terrestrial carbon to the atmosphere via global streams and rivers". Led by Shaoda Liu at Yale (now at Beijing Normal University), this paper presents the first global climatology of river CO2 emissions and monthly river and stream surface area estimates. It was great working with this collaborative group.

Feb 11, 2022—PhD student, Emily Ellis, submits a Future Investigators in NASA Earth and Space Science and Technology (FINESST) proposal entitled "Remote Sensing of River Temperature and Discharge: Defining Connections and Assessing Changes." Fingers crossed, Emily!  

Feb 11, 2022—NASA Water Resource Applications proposal selected for funding, "Satellite Assisted Operational Reservoir Evaporation Monitoring and Forecasts for the Western U.S." (PI: Huilin Gao, Co-I: George Allen). 

January 24, 2022—Hank Harrington joins the Global Rivers Group as a TAMU Water Management & Hydrological Science MS Student. He will be working on the Brazos River plastics project, funded by the TAMU PESCA program. 

December 17, 2021—TAMU GRG is looking to recruit a PhD student, starting Fall 2021. Five years of funding available. Review of applicants start Feb 1st, 2022. 


December 16, 2021—George receives an NSF CAREER Award from Hydrologic Sciences and Geomorphology & Land-use Change programs.  The title of the proposal is CAREER: Integrating river hydrology across scales: advancing understanding of the global river-atmosphere interface. 


December 13, 2021—George, Ryan, Emily, John and Molly attend the AGU Fall meeting in New Orleans. Emily, John, Ryan and George are presenting their research, so come check it out!  


November 16, 2021—Paper led by Ryan Riggs published in Environmental Modelling & Software. This paper presents the RODEO algorithm and Google Earth Application, enabling remote sensing of discharge at the click of a button:


November 11, 2021—GRG graduate student member Ennis Rios passes his Final Oral Exam for his Masters in Water Management. Ennis will be working as a researcher at the Texas Water Resources Institute (TWRI). Congratulations, Ennis!! 


October 19, 2021—Delia Pastore joins the Global Rivers Group as an undergraduate research assistant. She will be working on the PESCA-funded project on quantifying microplastic dynamics in the Brazos River using remote sensing. Welcome Delia! 

September 22, 2021—Paper led by Ann Stavert at CSIRO Oceans and Atmosphere published in Global Change Biology. Global Carbon Project study explores patterns, trends, and drivers of increasing global methane emissions:

August 16, 2021—Molly Stroud (BA Dartmouth) joins the Global Rivers Group as an MS student. Molly will work on constraining observational requirements needed to track sediment dynamics within Earth's inland water bodies. Her research is funded by a NASA-Caltech Jet Propulsion Laboratory Strategic University Research Partnership (SURP) grant. Welcome to Texas, Molly!

August 12, 2021—Science Magazine covers findings presented in Zipper et al., (2021): Climate change is drying out many part-time streams in the United States

July 31, 2021—Paper led by Sam Zipper at Kansas Geological Survey published in Environmental Research Letters. Study reveals widespread changes in flow intermittency across the United States rivers and streams:

July 1, 2021 —Emily Ellis (MS, BS, Oklahoma State) joins the Global Rivers Group as a PhD student. Emily is the recipient of the MERIT Fellowship, the most prestigious University fellowship bestowed upon graduate students at Texas A&M. Welcome, Emily! 

June 30, 2021—Ryan Riggs receives the TX Space Grant Consortium Graduate Fellowship to support his dissertation research on the topic of remote sensing of river discharge. Congratulations, Ryan! 


June 25, 2021—JPL Strategic University Research Program (SURP) Proposal approved for funding: "Assessing altimetry and optical remote sensing products to study global sediment transport dynamics in Earth’s inland water bodies" (JPL PI: Marc Simard, TAMU PI: George Allen).