Study advances understanding of massive ocean carbon reservoir and its impact to marine food web
The oceans hold a vast reservoir--700 billion tons--of carbon, dissolved in seawater as organic matter, often surviving for thousands of years after being produced by ocean life. Yet, little is known about how it is produced, or how it's being impacted by the many changes happening in the ocean.
Left: Sampling locations showing the dissolved organic carbon concentration measured at the surface (dots) over Chlorophyll recorded from satellite (background) Right: Dissolved organic carbon calculated (background) compared with the measured dissolved organic carbon (dots)
Image: Cristina Romera-Castillo, et.al. Satellite
Image: SeaWiFS Project NASA Goddard Space Flight Center
Think of dissolved organic carbon, or DOC, in the ocean as tree leaves and other dead organic matter falling to the forest ground--a portion of this natural carbon sustains life while the remainder remains hidden in the soils, being sequestered for many years. As is true in the forests, this vital, residual carbon reservoir is necessary to sustain life in the ocean, and to sequester vast amounts of carbon in its great depths.
To better understand this important pool of ocean carbon, researchers at the University of Miami (UM) Rosenstiel School of Marine and Atmospheric Science used data collected over the past 15 years on several international scientific cruises to map the distribution of this material in the Atlantic Ocean. From the analysis, they found that this major basin contributes one third of the global ocean net production of dissolved organic carbon.
"Carbon is involved in all aspects of our life," said Dennis Hansell, UM Rosenstiel School professor of ocean sciences and coauthor of the study. "We need to understand the carbon cycle on Earth especially as we add more from the burning of fossil fuels."
Dissolved organic carbon is the primary food source at the base of the marine food chain. It is produced by phytoplankton during photosynthesis, and it is mostly consumed by microbial life. The remainder that is not consumed by microbes accumulates in the ocean.
The researchers discovered that the production of dissolved organic carbon at the ocean's surface could be accurately predicted by measuring the amount of nutrients arriving into the euphotic, or sunlit, zone. The nutrients arrive there mostly by winter mixing and upwelling, and in turn support the growth of ocean plant life. From the arrival of nutrients to the surface ocean, they estimated the resulting plant growth and the production of residue, the DOC, from that growth. From those estimates, they built a map of DOC at the surface of the entire Atlantic Ocean.
"In our work, we found that the production of dissolved organic carbon depends on the quantity of nutrients that reach the euphotic zone from deeper layers," said Cristina Romera-Castillo, a former postdoctoral researcher at the UM Rosenstiel School and lead author of the study. "In future scenarios, how climate change will affect the nutrient arrival to the surface ocean will determine the inventory of dissolved organic carbon in the ocean."
This inventory in turn affects the cycling of carbon on Earth, which has important roles in climate.
The paper, titled "New nutrients exert fundamental control on dissolved organic carbon accumulation in the surface Atlantic Ocean," was published in the Proceedings of the National Academy of Sciences. The study's authors include: Cristina Romera-Castillo, who conducted the work while a postdoctoral researcher at the UM Rosenstiel School, UM Rosenstiel School Professor of Ocean Sciences Dennis Hansell, and Robert T. Letscher from the University of California Irvine.
The study was funded by grants from the National Science Foundation, Grant# OCE1436748 and the U.S. Department of Energy's Scientific Discovery through Advanced Computing program, Grant# DE-SC0012550
About the University of Miami's Rosenstiel School
The University of Miami is one of the largest private research institutions in the southeastern United States. The University's mission is to provide quality education, attract and retain outstanding students, support the faculty and their research, and build an endowment for University initiatives. Founded in the 1940's, the Rosenstiel School of Marine & Atmospheric Science has grown into one of the world's premier marine and atmospheric research institutions. Offering dynamic interdisciplinary academics, the Rosenstiel School is dedicated to helping communities to better understand the planet, participating in the establishment of environmental policies, and aiding in the improvement of society and quality of life. For more information, visit: http://www.
Diana Udel | EurekAlert!
Diving robots find Antarctic seas exhale surprising amounts of carbon dioxide in winter
16.08.2018 | National Science Foundation
Diving robots find Antarctic winter seas exhale surprising amounts of carbon dioxide
15.08.2018 | University of Washington
There are currently great hopes for solid-state batteries. They contain no liquid parts that could leak or catch fire. For this reason, they do not require cooling and are considered to be much safer, more reliable, and longer lasting than traditional lithium-ion batteries. Jülich scientists have now introduced a new concept that allows currents up to ten times greater during charging and discharging than previously described in the literature. The improvement was achieved by a “clever” choice of materials with a focus on consistently good compatibility. All components were made from phosphate compounds, which are well matched both chemically and mechanically.
The low current is considered one of the biggest hurdles in the development of solid-state batteries. It is the reason why the batteries take a relatively long...
New design tool automatically creates nanostructure 3D-print templates for user-given colors
Scientists present work at prestigious SIGGRAPH conference
Most of the objects we see are colored by pigments, but using pigments has disadvantages: such colors can fade, industrial pigments are often toxic, and...
Scientists at the University of California, Los Angeles present new research on a curious cosmic phenomenon known as "whistlers" -- very low frequency packets...
Scientists develop first tool to use machine learning methods to compute flow around interactively designable 3D objects. Tool will be presented at this year’s prestigious SIGGRAPH conference.
When engineers or designers want to test the aerodynamic properties of the newly designed shape of a car, airplane, or other object, they would normally model...
Researchers from TU Graz and their industry partners have unveiled a world first: the prototype of a robot-controlled, high-speed combined charging system (CCS) for electric vehicles that enables series charging of cars in various parking positions.
Global demand for electric vehicles is forecast to rise sharply: by 2025, the number of new vehicle registrations is expected to reach 25 million per year....
17.08.2018 | Event News
08.08.2018 | Event News
27.07.2018 | Event News
21.08.2018 | Power and Electrical Engineering
21.08.2018 | Life Sciences
21.08.2018 | Medical Engineering