In a groundbreaking study published in Science, Stanford-led researchers have unveiled a hidden factor that could reshape our understanding of how oceans mitigate climate change. The team discovered never-before-seen mucus “parachutes” produced by microscopic marine organisms that significantly slow their sinking, effectively putting the brakes on a process crucial for removing carbon dioxide from the atmosphere.
Summary: Stanford researchers have discovered microscopic mucus structures that significantly slow the sinking of marine snow, potentially altering estimates of the ocean’s carbon sequestration capacity. This finding underscores the importance of studying natural processes in their true environments for accurate climate modeling.
Estimated reading time: 9 minutes
This surprising discovery implies that previous estimates of the ocean’s carbon sequestration potential may have been overestimated. However, it also paves the way for improving climate models and informing policymakers in their efforts to slow climate change.
The Biological Pump: A Carbon Dioxide Shuttle
Marine snow, a mixture of dead phytoplankton, bacteria, fecal pellets, and other organic particles, plays a vital role in the Earth’s carbon cycle. This natural phenomenon absorbs about a third of human-made carbon dioxide from the atmosphere and shuttles it down to the ocean floor, where it remains locked away for millennia. Scientists have long known about this process, dubbed the “biological pump,” but the exact mechanics of how these delicate particles fall through the ocean’s vast depths (averaging 4 kilometers or 2.5 miles) has remained a mystery until now.
Manu Prakash, an associate professor of bioengineering and of oceans at Stanford University and senior author of the study, emphasized the importance of this discovery: “We haven’t been looking the right way. What we found underscores the importance of fundamental scientific observation and the need to study natural processes in their true environments. It’s critical to our ability to mitigate climate change.”
A Revolutionary Approach to Marine Observation
The research team unlocked this mystery using an innovative invention – a rotating microscope developed in Prakash’s lab. This unique device moves as organisms move within it, simulating vertical travel over infinite distances while adjusting aspects such as temperature, light, and pressure to emulate specific ocean conditions.
Over the past five years, Prakash and his team have brought their custom-built microscopes on research vessels to all the world’s major oceans. On a recent expedition to the Gulf of Maine, they collected marine snow using hanging traps in the water, then rapidly analyzed the particles’ sinking process in their rotating microscope.
The results were stunning. The researchers observed that marine snow sometimes creates parachute-like mucus structures that effectively double the time the organisms linger in the upper 100 meters of the ocean. This prolonged suspension increases the likelihood of other microbes breaking down the organic carbon within the marine snow particles and converting it back into readily available organic carbon for other plankton – effectively stalling carbon dioxide absorption from the atmosphere.
Implications for Climate Science and Policy
The discovery of these mucus “parachutes” has significant implications for our understanding of ocean carbon sequestration and, by extension, climate change mitigation efforts. The findings suggest that current models may be overestimating the ocean’s capacity to absorb and store carbon dioxide.
This revelation underscores the need for more accurate and detailed observations of natural processes in their true environments. As Prakash notes, “We cannot even ask the fundamental question of what life does without emulating the environment that it evolved with. In biology, stripping it away from its environment has stripped away any of our capacity to ask the right questions.”
The Importance of Observation-Driven Research
The study serves as a prime example of observation-driven research, essential to understanding how even the smallest biological and physical processes work within natural systems. Rahul Chajwa, the study’s lead author and a postdoctoral scholar in the Prakash Lab, emphasized this point: “Theory tells you how a flow around a small particle looks like, but what we saw on the boat was dramatically different. We are at the beginning of understanding these complex dynamics.”
The researchers argue that supporting research that prioritizes observation in natural environments should be a priority for public and private organizations that fund science. This approach could lead to more accurate climate models and inform more effective policies for addressing climate change.
Looking Ahead: Refining Models and Expanding Research
Moving forward, the research team is working to refine their models and integrate the datasets into Earth-scale models. They plan to release an open dataset from the six global expeditions they have conducted so far, which will be the world’s largest dataset of direct marine snow sedimentation measurements.
The team also aims to explore factors that influence mucus production, such as environmental stressors or the presence of certain species of bacteria. Despite the challenges their discovery poses to current understanding, the researchers remain hopeful. On a recent expedition off the coast of Northern California, they discovered processes that can potentially speed up carbon sequestration.
As Prakash concluded, “Every time I observe the world of plankton via our tools, I learn something new.” This sentiment encapsulates the essence of scientific discovery and the ongoing quest to understand our planet’s complex systems.
Further Reading
For more information on this research and related topics, please visit:
- Full study published in Science
- Stanford University School of Engineering
- Stanford Doerr School of Sustainability
- Woods Hole Oceanographic Institution
Quiz: Test Your Knowledge
- What is marine snow?
- How does the newly discovered mucus “parachute” affect marine snow sinking?
- Why is the rotating microscope important for this research?
Answer Key:
- Marine snow is a mixture of dead phytoplankton, bacteria, fecal pellets, and other organic particles that absorbs carbon dioxide from the atmosphere.
- The mucus “parachute” significantly slows the sinking of marine snow, doubling the time it lingers in the upper 100 meters of the ocean.
- The rotating microscope allows researchers to observe marine snow in its natural environment, simulating vertical travel over long distances while adjusting for specific ocean conditions.
Glossary of Terms
- Biological pump: The ocean’s process of absorbing atmospheric carbon dioxide through marine organisms and transporting it to the deep sea.
- Marine snow: A mixture of organic particles that sink from the upper layers of the ocean to the deep sea.
- Exopolymer: A type of mucus-like substance produced by marine microorganisms.
- Euphotic zone: The upper layer of the ocean that receives enough light for photosynthesis to occur.
- Remineralization: The process by which organic matter is broken down into its constituent inorganic components.
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