A recent study uncovers that the shape and depth of the ocean floor play a crucial role in carbon sequestration. This discovery could revolutionize climate change strategies and aid in the search for habitable planets.
Recent breakthroughs in climate science may hold the key to better understanding and combating global climate change. A groundbreaking study has revealed that the shape and depth of the ocean floor play a significant role in the long-term carbon cycle, accounting for up to 50% of changes in how carbon has been sequestered in the ocean over the last 80 million years.
Historically, scientists have understood that Earth’s oceans are the planet’s largest carbon sinks, absorbing more carbon dioxide than any other natural system. However, the exact mechanisms of how changes in seafloor topography have influenced this process remained elusive until now.
Matthew Bogumil, a doctoral student at UCLA and the lead author of the study, emphasized the novelty of the findings. “We were able to show, for the first time, that the shape and depth of the ocean floor play major roles in the long-term carbon cycle,” he said in this UCLA news release.
The study, published in the Proceedings of the National Academy of Sciences, painstakingly reconstructed the bathymetry — or underwater topography — of the ocean floor over the past 80 million years. The researchers integrated this data into a complex computer model that measures marine carbon sequestration. Their results suggested that the distribution and depth of both shallow and deep marine regions are pivotal in understanding carbon storage processes.
Tushar Mittal, co-author and professor of geosciences at Pennsylvania State University, elaborated on the paradigm shift these findings represent. “Typically, carbon cycle models over Earth’s history consider seafloor bathymetry as either a fixed or a secondary factor,” he noted. By bringing this variable to the forefront, the study challenges long-standing assumptions about carbon sequestration factors.
The innovative research revealed that ocean alkalinity, calcite saturation states and carbonate compensation depths — all key indicators of carbon sequestration — are heavily influenced by changes in seafloor topography. For the Cenozoic era, the study found that bathymetry changes alone accounted for 33% to 50% of observed variations in carbon storage.
These findings have profound implications for current and future climate policies.
“Understanding important processes in the long-term carbon cycle can better inform scientists working on marine-based carbon dioxide removal technologies to combat climate change today,” said Bogumil.
The research suggests that ignoring bathymetric changes could lead to incorrect attributions of carbon sequestration differences to less reliable factors such as atmospheric CO2 or water column temperatures.
Moreover, the study’s insights extend beyond Earth.
Carolina Lithgow-Bertelloni, a UCLA professor and department chair, highlighted the impact this new understanding could have in the search for habitable planets. “Now that we understand the important role bathymetry plays in the carbon cycle, we can directly connect the planet’s interior evolution to its surface environment when making inferences from JWST [James Webb Space Telescope] observations and understanding planetary habitability in general,” she explained.