About 10% of U.S. oysters can be found in the waters of the bay. The bay is warming and its waters are acidic because of rising carbon dioxide levels. In 2020 the state banned oyster harvesting. Climate scientists were encouraged to conduct an experiment to see if they could reverse the changes in the water.

The researchers injected 2000 liters of sea water enriched with lime, an alkaline powder and a primary ingredient in cement that is derived from chalk or limestone. They showed it was able to draw CO 2 out of the air.

The technique of ocean liming is new to them. The work was presented this week at a meeting of the American Geophysical Union.

The experiment is a test of the controversial idea of altering the atmosphere or ocean to counteract the effects of rising CO 2 Ken Caldeira is a climate scientist at the Carnegie Institute for Science. He says that demonstrations can show that small-scale changes do not cause long-term damage to the environment.

30% of carbon emissions are absorbed by the ocean. The CO 2 combined with calcium and other ion depletes them. As a result, the pH of the waters drops. The goal is to reset the water chemistry.

One approach is liming The addition of calcium hydroxide raises the water's pH and allows it to sequester more CO 2 in the form of calcium bicarbonate or as carbonate deposited in the shells of sea creatures. The way the ocean naturally removes CO 2 is enhanced by the liming. We speed up natural processes and make them happen on time.

A report from the National Academies of Sciences, Engineering, and Medicine called for 2.5 billion dollars in ocean engineering research over the next 10 years. The limits of what can be learned in the lab are being faced by researchers. The lab isn't able to show you how a cloud of alkali can spread through the ocean, how particles might clump up, or how the chemicals might affect marine life. She says that they need to go in the field.

The oyster decline was studied by the officials at the National Estuarine Research Reserve. They agreed when he mentioned a trial. The Notre Dame–led team used a dye to follow the water. They found that the pH levels in the water did not go up too much. McGillis says that they got a nice small change. They conducted one release deeper in the estuary, off a long pier, where the levels of dissolved CO 2 had already been reduced. The lime reduced CO 2 levels by another 70 parts per million. There were no red flags during the trial.

One way to increase ocean carbon storage is liming. Iron-coated rice husks were spread across the Arabian Sea by researchers from the Centre for Climate Repair at the University of Cambridge. The researchers wanted to add iron to the ocean in order to fertilize a bloom of algae that would absorb carbon and sequester it when they die. After the deployment, a storm stirred up the husks and made their effect difficult to see. Hugh Hunt is a Climate Engineer with the Cambridge team. In order to create a carbon-hungry submarine forest, researchers have tried to cultivate giant kelp off the coast of Namibia.

The trial in Florida is not the first of its kind. A part of Australia's Great Barrier Reef was added to by Caldeira and colleagues in 2004. They were able to increase the natural calcification of the reef because of it. The advantage of lime is that it is already produced for the cement industry.

The approach would be impractical as a global solution. It is difficult to make alkaline Additives without emitting CO 2 The amount of gas that is released by heating limestone to make lime is partially offset by the ocean. It would be too expensive to dump low emission lime into the ocean.

As CO 2 continues to rise and a climate solution grows more tempting, ocean liming has a key advantage over other ideas. Throwing particles in the air isn't as controllable as altering the chemistry of the water. For a long time, particles can stay in the sky. He says that ocean salts only last a month before being dispersed. If it goes south, there will be more control.