A pair of dissolved organic carbon maps show the carbon and chlorophyl concentrations recorded by both direct water sampling and satellite imaging. Photo by Cristina Romera-Castillo, et.al./SeaWiFS Project/NASA Goddard Space Flight Center
MIAMI, Oct. 18 (UPI) -- Carbon is everywhere -- including the ocean floor. A new map is helping scientists study the distribution of residual carbon in the Atlantic Ocean.
Decaying plant and animal matter is responsible for a massive reservoir of what's called dissolved organic carbon, or DOC. Like leaf litter on the forest floor, DOC is concentrated in and on the seabed. A portion of the carbon supports life, while the rest is stored in ocean sediments -- sometimes for thousands of years.
To build a map of dissolved carbon in the Atlantic, scientists at the University of Miami amassed oceanic data collected by research vessels over the last 15 years. Included in the data were measurements of dissolved organic carbon measured via direct sampling and satellite imaging.
DOC is produced by phytoplankton during photosynthesis, and phytoplankton rely on nutrients brought to the ocean's surface by upwelling, when vertical currents deliver deep-lying, cold, oxygenated water to the surface.
"The production of dissolved organic carbon depends on the quantity of nutrients that reach the euphotic zone from deeper layers," Cristina Romera-Castillo, a former postdoctoral researcher at Miami, said in a news release. "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."
Romera-Castillo is the lead author of a new paper on the distribution of dissolved organic carbon in the Atlantic -- published this week in the journal PNAS. The findings suggest the Atlantic Ocean is responsible for the production of as much as a third of the world's dissolved organic carbon.
Understanding the movement of carbon throughout the planet's various oceanic, geologic and climatic cycles will help researchers better predict the effects of climate change.
"Carbon is involved in all aspects of our life," added study co-author Dennis Hansell, a professor of ocean sciences at Miami. "We need to understand the carbon cycle on Earth especially as we add more from the burning of fossil fuels."
