The Limitations of Traditional Methods

Hydrologists, the scientists dedicated to studying water, face significant challenges in their work due to the sparse distribution of monitoring tools. With only around 3,000 river gauge stations globally, most areas remain undermonitored. These stations provide critical data only at specific locations, making it difficult to assess broader hydrological trends.

Colin Gleason, an Armstrong Professional Development Professor of Civil and Environmental Engineering at the University of Massachusetts, Amherst, highlights this issue: “The best way to study a river is to get your feet wet and visit it yourself. The second best way is to use a river gauge.”

Introducing Confluence: The Future of River Monitoring

Recently, a groundbreaking solution has emerged to address these challenges. Developed by Gleason and a team of over 30 researchers, Confluence represents a significant advancement in hydrology. This analytic framework integrates data from NASA’s Surface Water and Ocean Topography (SWOT) mission and the Harmonized Landsat Sentinel-2 archive (HLS) to estimate discharge and suspended sediment levels for every river wider than 50 meters across the globe.

Hosted on NASA’s Physical Oceanography Distributed Active Archive Center (PO.DAAC), Confluence is available as open-source software, accessible to researchers worldwide at no cost. Its dual use of altimetry data from SWOT for discharge and optical data from HLS for sediment allows hydrologists to create comprehensive, timely models of river size and quality on a global scale.

Advantages of Confluence

The revolutionary aspect of Confluence lies in its ability to combine two major sources of satellite data in a single processing pipeline. This integration marks the first time such broad hydrological parameters can be estimated globally with a single tool.

Compared to traditional workflows for sediment analysis using HLS data, Confluence accelerates processing by a factor of 30, making it a highly efficient solution for hydrologists.

The Development of Confluence

Nikki Tebaldi, a Cloud Adoption Engineer at NASA’s Jet Propulsion Laboratory (JPL) and Co-Investigator for Confluence, was the lead developer of the project. Despite the challenges of integrating decades-old algorithms, Tebaldi remains optimistic about the outcome. “I’m really proud that we’ve pieced together all of these different algorithms, got them into the cloud, and we have them all executing commands and working,” she expressed.

This collaborative effort showcases how NASA’s focus on data integration and cloud computing can lead to transformative advancements in environmental monitoring. The Confluence framework exemplifies the power of combining multiple data sources for more accurate and comprehensive analysis.

The Impact of Confluence

The ability to generate global, real-time estimates of river discharge and quality will significantly enhance numerous hydrological applications. With this new data, researchers can better assess the health of river ecosystems, improve flood predictions, and monitor snowmelt impacts.

Suresh Vannan, former manager of PO.DAAC and a Co-Investigator for Confluence, underscores the importance of these advancements. “There are a bunch of science applications that river discharge can be used for, because it’s pretty much taking a snapshot of what the river looks like, how it behaves. Producing that snapshot on a global scale is a game changer,” Vannan stated.

Accessing Confluence Source Code

While the Confluence team continues to refine their software package, users can already access the source code on GitHub. For tutorials, manuals, and other user guides, explore the PO.DAAC webpage here.

Funding and Collaboration

This project was made possible by NASA’s Advanced Intelligent Systems Technology (AIST) program within the Earth Science Technology Office (ESTO). Collaboration between AIST, SWOT, and PO.DAAC underscores the agency’s commitment to developing innovative technologies for the study of Earth from space.

For more information on opportunities to contribute to next-generation Earth observation technologies, visit ESTO’s funding page.

Conclusion

From simple river gauges to sophisticated satellite data integration, the field of hydrology is constantly evolving. NASA’s Confluence framework stands as a testament to this progress, offering groundbreaking tools to researchers and policy-makers worldwide. With Confluence, hydrologists can now monitor river health and behavior on a global scale, leading to better-informed decisions about water resource management and environmental protection.