TACC Supercomputing Powers Climate Modeling for Fisheries

A tremendous portion of the world depends on the output of the oceans’ major fisheries, which have, in recent decades, found themselves under near-constant threat from mismanagement (e.g. overfishing). Climate change, of course, clouds the future of these fisheries even more – and now, researchers are leveraging the power of supercomputing to predict how climate shifts will affect upwelling, a process crucial to sustaining major fisheries.

Upwelling is important to fisheries because it brings cool, nutrient-rich water closer to the surface, where the fish that constitute fisheries benefit from those nutrients. “We’re interested in how climate change is going to alter upwelling and how the sustainability of the future fisheries will be impacted,” explained Ping Chang, chair of oceanography at Texas A&M University, in an interview with Faith Singer of the Texas Advanced Computing Center (TACC).

“A lot of papers written in the past use coarse-resolution models that don’t resolve upwelling very well,” Chang added. For this research, they used a much higher-resolution climate model with grid squares around 10km2 – much more suitable for assessing upwelling, which can occur across fairly localized areas. The model was run on Frontera, which ranked 19th on the most recent Top500 list with 23.5 Linpack petaflops.

“TACC is unique in providing resources for researchers like us to tackle the fundamental questions of science,” Chang said. “Our goal is not routine forecasts. What we want is a better understanding of the Earth system dynamics that are missing in current climate models to make our model and our methods better. Without Frontera, I don’t know if we could make simulations like we do. It’s critical.”

Using this high-resolution coupled climate modeling and real historical data, the researchers are working to evaluate their ability to forecast climate effects on upwelling. “It turns out that when we increase the resolution of our climate models, we find that the upwelling simulation becomes much closer to reality,” Chang said. For now, the model is working in five-year increments: “There’s a limit to how far out you can make a forecast. Beyond a certain time limit, the model no longer has skill. At five years, our model still shows useful skill.”

The project, funded by the NSF, is one of 16 related projects that all address the “Blue Economy” (sustainable economic use of ocean resources). The researchers hope to develop reliable medium- to long-term fishery forecasts, and while some prior researchers had predicted stronger upwelling from a warmer climate, Chang isn’t so sure.

“High-resolution models so far predict upwelling in most areas not increasing,” Chang said. “The models are predicting warmer, not colder temperatures in these waters. In Chile and Peru, the warming is quite significant — 2-3ºC warming in the worst case scenario, which is business as usual. That can be bad news for upwelling.”

To learn more about this research, read the reporting from TACC’s Faith Singer here.