Marika Holland, chief scientist for NCAR’s Community Earth System Modeling Project, said the new supercomputer is “close to a game-changer. We’ve had incremental improvements in our computational resources over time, but . . . Yellowstone is a whole new scale, and there are things that we will be able to explore that just were not possible before.”
As climate models become more complex and detailed, limited computing power bottlenecks the research. Broad-brush models use less power, but they often cannot consider details that drive local climate, such as complex coastlines or the mountain ranges and valleys that affect rainfall. Researchers refer to this as a problem of “model resolution.”
“If you have an old digital camera that doesn’t have as many megapixels as a new one, you want to get that [new] camera because it takes sharper pictures, and you can store a lot more pictures on it,” said Richard Loft, a director in the computing lab at NCAR.
“It’s the same thing with Yellowstone. We’ve increased our ability to generate more-detailed pictures of the climate system, so we get a sharper, crisper view of things.”
Yellowstone will be able to generate climate projections for seven-square-mile “pixels,” instead of the 60-square-mile units typically in use now. “We’ve already had the model resolution to confirm the warming of the planet but not to talk about the winners and losers at the regional scale,” Loft said.
The new computer will cost about $30 million; it will be operated by NCAR, which is funded by the National Science Foundation. And just like your own computer, it is likely to be obsolete and ready for replacement by a faster model in about four years.
Yellowstone and its successors will allow modelers to provide a more reliable range of possible answers for local climate questions: How dry will it be by mid-century, say, in the watersheds that feed the Prettyboy and Loch Raven reservoirs, which supply much of Baltimore’s water? How high will summer heat spike in the Shenandoah Valley? Where can Florida panthers and loblolly pine, a major source of timber, survive as the climate shifts?
“Many climate scientists out there are itching to be able to do higher-resolution simulations and more experiments,” Holland said. “One of our working groups has strong links with water resource managers and water utilities. For them, models of sea-level rise, vegetation, snowpack, precipitation and stream-flow changes are all important. Those planners are living with the uncertainty of how climate changes are going to occur.”