Three Georgia Tech School of Earth and Atmospheric Sciences researchers — Professor and Associate Chair Annalisa Bracco, Professor Taka Ito, and Georgia Power Chair and Associate Professor Chris Reinhard — will join colleagues from Princeton, Texas A&M, and Yale University for an $8 million Department of Energy (DOE) grant that will build an “end-to-end framework” for studying the impact of carbon dioxide removal efforts for land, rivers, and seas. 

The proposal is one of 29 DOE Energy Earthshot Initiatives projects recently granted funding, and among several led by and involving Georgia Tech investigators across the Sciences and Engineering.

Overall, DOE is investing $264 million to develop solutions for the scientific challenges underlying the Energy Earthshot goals. The 29 projects also include establishing 11 Energy Earthshot Research Centers led by DOE National Laboratories. 

The Energy Earthshots connect the Department of Energy's basic science and energy technology offices to accelerate breakthroughs towards more abundant, affordable, and reliable clean energy solutions — seeking to revolutionize many sectors across the U.S., and relying on fundamental science and innovative technology to be successful.

Carbon Dioxide Removal 

The School of Earth and Atmospheric Sciences project, “Carbon Dioxide Removal and High-Performance Computing: Planetary Boundaries of Earth Shots,” is part of the agency’s Science Foundations for the Energy Earthshots program. Its goal is to create a publicly-accessible computer modeling system that will track progress in two key carbon dioxide removal (CDR) processes: enhanced earth weathering, and global ocean alkalinization. 

In enhanced earth weathering, carbon dioxide is converted into bicarbonate by spreading minerals like basalt on land, which traps rainwater containing CO2. That gets washed out by rivers into oceans, where it is trapped on the ocean floor. If used at scale, these nature-based climate solutions could remove atmospheric carbon dioxide and alleviate ocean acidification. 

The research team notes that there is currently “no end-to-end framework to assess the impacts of enhanced weathering or ocean alkalinity enhancement — which are likely to be pursued at the same time.” 

 “The proposal is for a three-year effort, but our hope is that the foundation we lay down in that time will represent a major step forward in our ability to track carbon from land to sea,” says Reinhard, the Georgia Power Chair who is a co-investigator on the grant. 

“Like many folks interested in better understanding how climate interventions might impact the Earth system across scales, we are in some ways building the plane in midair,” he adds. “We need to develop and validate the individual pieces of the system — soils, rivers, the coastal ocean — but also wire them up and prove from observations on the ground how a fully integrated model works.”

That will involve the use of several existing computer models, along with Georgia Tech’s PACE supercomputers, Professor Ito explains. “We will use these models as a tool to better understand how the added alkalinity, carbon and weathering byproducts from the soils and rivers will eventually affect the cycling of nutrients, alkalinity, carbon and associated ecological processes in the ocean,” Ito adds. “After the model passes the quality check and we have confidence in our output, we can start to ask many questions about assessment of different carbon sequestration approaches or downstream impacts on ecosystem processes.”

Professor Bracco, whose recent research has focused on rising ocean heat levels, says CDR is needed just to keep ocean systems from warming about 2 degrees centigrade (Celsius). 

“Ninety percent of the excess heat caused by greenhouse gas emissions is in the oceans,” Bracco shares, “and even if we stop emitting all together tomorrow, that change we imprinted will continue to impact the climate system for many hundreds of years to come. So in terms of ocean heat, CDRs will help in not making the problem worse, but we will not see an immediate cooling effect on ocean temperatures. Stabilizing them, however, would be very important.”

Bracco and co-investigators will study the soil-river-ocean enhanced weathering pipeline “because it’s definitely cheaper and closer to scale-up.” Reverse weathering can also happen on the ocean floor, with new clays chemically formed from ocean and marine sediments, and CO2 is included in that process. “The cost, however, is higher at the moment. Anything that has to be done in the ocean requires ships and oil to begin,” she adds.

Reinhard hopes any tools developed for the DOE project would be used by farmers and other land managers to make informed decisions on how and when to manage their soil, while giving them data on the downstream impacts of those practices.

“One of our key goals will also be to combine our data from our model pipeline with historical observational data from the Mississippi watershed and the Gulf of Mexico,” Reinhard says. “This will give us some powerful new insights into the impacts large-scale agriculture in the U.S. has had over the last half-century, and will hopefully allow us to accurately predict how business-as-usual practices and modified approaches will play out across scales.”