Water in the West: a future of uncertainty

Utah State University hosted the Spring Runoff Conference on Tuesday, highlighting water challenges in the western United States and the hurdles the region will face. Alan Rhoades, a hydroclimate specialist from the Lawrence Berkeley National Laboratory, spoke at the conference on his work to overcome the uncertainty of the future by assessing the performance of novel climate modeling techniques.

For Utah and the West, global climate change is expected to drastically impact our snowpack: the natural water storage reservoir for populations around the Rockies and Sierra Nevadas. One major problem for scientists and stakeholders working to adapt to a new climate is that different carbon emission scenarios and different data analyses techniques provide different projections for the future of snow.

“Stakeholders and I are ascending this mountain of information and uncertainty, and we’re trying to do this together,” Rhoades said.

There are about 30 global climate models. These models accurately simulate climate through

mathematical representations of the interactions between the atmosphere, land surface, ocean and sea ice. Behind each model are numerous technicians and researchers, unfathomable computing power, and pages of cryptic computer code.

By standing on the shoulders of giants, modern day climate modelers like Rhoades have uncovered much about climate and the impact of carbon dioxide on the Earth’s energy budget.

Climate and weather are difficult to understand because there is only one Earth. There is no way to compare and contrast how climate would be different without mountains, or with different concentrations of greenhouse gasses when scientists only have one test subject. Climate models fill this gap by increasing the sample size with realistic earth system representations that are used to determine how climate change will impact the earth system, precipitation and snowpack.

Water managers in the West want to get their hands on this information to prepare for a world with less snowpack and more people who need water, but Rhoades said our current problem is related to the scale of climate data. He works with a team of scientists to downscale or improve the resolution of climate data for practical use in watersheds and regions with complex topography.

Rhoades says scientists can bridge this gap in data and practical solutions through communication and cooperation. “We’re engaging with stakeholder communities early on in the project to make sure that we’re evaluating models in a way that’s useful to them,” Rhoades said. “Stakeholders really get a chance to shape the science and learn about the nuances of science.”

Rhoades’ team is trying to, “break down this ivory tower approach to science,” by interacting with water managers and stakeholders before their research begins to deliver more practical and usable information.

This approach can be challenging.  

The diversity of water issues in the West requires equally diverse research approaches. “I always heard the term water stakeholder and water manager but throughout the project I’ve learned that the term is as diverse as academic disciplines themselves,” Rhoades said. “They have a lot of things they are trying to balance in their own basins.”

On top of diverse issues, water stakeholders in Utah and the West are facing catastrophic projections for snowpack and snow water equivalent, the water content in snowpack.

“By end century, some models are predicting that we’ll have about 80 percent decline in snow water equivalent,” Rhoades said, as an audible murmur rose from the audience of water researchers and managers.

“That would change the world,” said Jack Schmidt, a USU professor in watershed sciences. “You’re talking about ending life in California as we know it with ramifications throughout the United States.”

“I can’t believe a stakeholder would say, ‘thanks for that information, now let’s go have lunch,’” Schmidt said.

 “When you’re presenting a dramatic number like 80 percent, there might be a tendency of some people to dismiss that,” said David Tarboton, a specialist in hydrology.

“There are physical mechanisms behind this understanding that leads us to believe that this is a possibility,” Rhoades said. The fate of the region’s snowpack, “depends on which emission scenario we end up going on. Currently we’re headed towards the high-emission scenario, but there’s time to try and change that trajectory.”

Through working cooperatively to produce climate research that is useful for water managers, the most difficult problems could come from trying to produce practical solutions for climate change adaptation.

Rhoades said the community of scientists and stakeholders are still processing the projected climate information, but they’ve made steps in the right direction.

“I think we’re trying to figure out ways to handle this,” Rhoades said. “We’re starting somewhere.”