Scientists achieve first quantitative measurement of global ocean carbon cycle

Just like plants on land, tiny plankton in the ocean consume carbon dioxide through photosynthesis and convert it into organic matter and oxygen. This biotransformation is known as the primary productivity of the ocean. In a new study recently published in Nature Geoscience, senior scientists at the Monterey Institute of Marine Biology and former MBARI postdoctoral fellows demonstrate how a fleet of robotic buoys is changing the understanding of ocean primary productivity on a global scale.

By converting carbon dioxide into organic matter, phytoplankton not only support the marine food web, they are also the first step in the ocean's biological carbon pump. The data collected by these robots will allow scientists to more accurately estimate how carbon flows from the atmosphere to the ocean and provide new clues to the global carbon cycle. Changes in phytoplankton productivity can have far-reaching effects, such as affecting the ocean's ability to store carbon and altering marine food webs, the researchers said.

"We already know that in warmer oceans, the primary production of marine phytoplankton will decrease, but we don't have the means to make global-scale measurements to validate the models." , and that marine primary productivity ebbs and flows with the climate system, but primary productivity "may rise in some places and fall in others, but we don't know how these will balance out." Direct observations on a global scale with seasonal and annual resolution are difficult and costly to obtain because of resource and human constraints. In contrast, satellite remote sensing or computer-generated circulation models can provide the required spatial and temporal resolution. "Satellite data can be used to create global maps of primary productivity, but these values are based on models rather than direct measurements."

Now, scientists have a new way to study ocean productivity - thousands of autonomous robots floating in the ocean, which Bif says allow scientists to understand primary productivity across regions, depths and times of the ocean. "This work is an important milestone in ocean data collection. We no longer have to actually go there to collect large amounts of data from the ocean."