Professor part of massive field lab researching global warming’s impact on water sources

At a time when a drought is affecting the 40 million people who rely on the Colorado River system, Indiana University professor Travis O’Brien and a team of scientific colleagues are embarking on a monumental U.S. Department of Energy project to better predict the future of water availability in the West.

The SAIL campaign — Surface Atmosphere Integrated Field Laboratory — kicked off at the beginning of September; the scientists will study the Upper Colorado River Basin for roughly the next two years. It’s the world’s first bedrock-to-atmosphere observation system, and will collect a massive amount of data to help scientists more accurately model water availability.

Studying the Upper Colorado River is important because it’s a key provider of hydroelectric power and fuels more than $1 trillion in economic activity. However, the drought has led to mandatory water consumption cuts for individual consumers and the agriculture industry.

“One of the goals at the top of the SAIL team’s minds is to understand the long-term climate change question of ‘How does global warming affect water sources in areas such as the Upper Colorado River Basin?'” said O’Brien, an assistant professor in the Department of Earth and Atmospheric Sciences in the IU Bloomington College of Arts and Sciences and visiting faculty at Lawrence Berkeley National Laboratory.

Scientists would like to better predict the timing and availability of water resources, specifically mountain watersheds, which supply 60 to 90 percent of water resources worldwide. The SAIL campaign will focus on the physical processes and land-atmosphere interactions affecting how Rocky Mountain watersheds deliver water.

Over nearly two full seasonal cycles, more than three dozen instruments such as radars, lidars, cameras and balloons will be used to measure precipitation, temperature, humidity, ozone and other key data points. The information is expected to improve Earth system models and better answer scientists’ questions about rainfall and snowfall, which will aid modeling that predicts future water availability.

O’Brien’s work will involve running atmospheric model simulations of conditions during the campaign, and using campaign observations to answer two questions:

• What drives extreme monsoon rainfall events in the region?
• In what ways do atmospheric/climate models need to be improved to better simulate precipitation in the mountainous West?

Understanding the impact of climate change on monsoons is important, O’Brien said, because they can affect reservoir water levels. To prevent flooding, their levels need to be handled differently for extreme rainfall than for steady rainfall. The availability of water and control of reservoirs also have a consequential effect on downstream rivers and ecology, he added.

The SAIL project also has the goal of accurately studying snow pack and how long it persists into spring, and when runoff begins to happen, O’Brien said.

“We know global climate change reduces the amount held in mountainous regions, but to what extent is unknown,” O’Brien said.

Two IU undergraduate students in the Department of Earth and Atmospheric Sciences, Libby McKesson and Miguel Contramaestre, will assist in the project by doing independent study research with O’Brien this semester. They’ll perform simulations of the southwestern U.S., including the SAIL campaign area.

O’Brien’s work on the SAIL project is funded through three sources:

• A Department of Energy grant to the Berkeley Lab, on which he is the local project investigator.
• A subcontract from the Berkeley Lab, through the Department of Energy-funded CASCADE project, to IU.
• Funds from Indiana University’s Environmental Resilience Institute.