What's Happening?
The Monterey Bay Aquarium Research Institute (MBARI) has deployed two 242.5-pound autonomous underwater vehicles (LRAUVs) off the coast of California as part of the 'Chasing Marine Snowstorms' expedition. These drones are designed to independently track
a drifting sediment trap by its acoustic beacon, photographing the top 656 feet of the ocean. The sediment trap, deployed from MBARI's flagship R/V David Packard, collects 'marine snow'—a mixture of mucus, dead plankton, and organic matter—at various depths down to 1,640 feet. This dual Eulerian-Lagrangian approach allows researchers to simultaneously observe what is sinking and what is still floating in the same moving body of water. The LRAUVs were pre-deployed from MBARI's cabled observatory (MARS) and motored to an offshore mooring before the research vessel even departed, demonstrating their advanced autonomous capabilities. This mission aims to measure the amount and composition of marine snow, which plays a crucial role in the ocean's biological carbon pump.
Why It's Important?
This research is critical for understanding the ocean's role in absorbing atmospheric carbon dioxide, a key factor in climate change. Marine snow represents a significant mechanism for sequestering carbon, as phytoplankton absorb CO2, and their remains, along with other organic matter, sink to the ocean floor, potentially locking carbon away for decades or centuries. Current climate models struggle to accurately account for the biological processes behind this carbon sinking. By precisely measuring the quantity and characteristics of marine snow, MBARI's expedition could fundamentally alter how scientists quantify the ocean's carbon absorption capacity. This improved understanding has direct implications for climate policy, economic models, and global climate projections, as it provides more accurate data on natural carbon sinks. The study's focus on the impact of El Niño conditions on marine snow further highlights its relevance to predicting future climate scenarios and their ecological consequences.
What's Next?
The LRAUVs and sediment trap are expected to continue their data collection through the winter, a period when MBARI anticipates El Niño to be at its strongest. This extended observation will provide crucial insights into how El Niño, characterized by warmer waters and reduced upwelling off California, affects the production and sinking of marine snow. Researchers will analyze the collected data to determine how changes in the food chain, influenced by El Niño, impact the amount and composition of organic matter reaching the deep ocean. MBARI is also scheduled to publish further logs and a wrap-up from the cruise, which will detail the success of the drones in tracking the trap and the initial findings. Additionally, the Sedimentation Event Sensor (SES) and SINKER cameras, which have been on the seafloor since April, were serviced and redeployed to continue recording, providing a continuous long-term dataset. NOAA's Climate Prediction Center is expected to release its next El Niño update on October 8, which will provide further context for the ongoing research.
Beyond the Headlines
The deployment of highly autonomous drones for oceanographic research signifies a broader shift towards advanced technological solutions in scientific exploration. The ability of these LRAUVs to operate independently for extended periods, track moving targets, and collect high-resolution data without direct human intervention, represents a significant leap in marine science capabilities. This approach not only enhances data collection efficiency but also allows for observations in challenging or remote environments that would be difficult or costly for manned expeditions. The research also touches upon the ethical implications of climate modeling and policy-making, emphasizing the need for accurate biological data to inform decisions that affect global ecosystems and human societies. The 'biological pump' mechanism, while natural, is a complex system whose efficiency can be altered by climate change, potentially creating feedback loops that further exacerbate global warming. Understanding these intricate processes is vital for developing effective mitigation strategies and adapting to a changing climate.
