This article has been reviewed according to Science X's editorial process and policies. Editors have highlighted the following attributes while ensuring the content's credibility: All the forests in the world pale in comparison to the ocean when it comes to absorbing carbon dioxide from the atmosphere. The ocean is the world's largest natural carbon sink, absorbing about a quarter of all CO2 emissions every year (and most of the excess heat trapped in Earth's atmosphere from greenhouse gases).
For one, there are natural limits to how much carbon the ocean can absorb and how quickly. Second, as CO2 dissolves in the ocean, it reacts with seawater. Those reactions release hydrogen ions, which make the water more acidic.
Since the Industrial Revolution, the surface ocean has become 30% more acidic on average, to the point that it's making life hard for organisms that build chalk-like shells and skeletons—including corals, coccolithophores and young oysters. Adding minerals that alter the chemistry of seawater, in a process called ocean alkalinity enhancement (OAE), is a proposed solution to address both of these challenges. As a "marine carbon dioxide removal" strategy, OAE would amplify natural processes in the ocean to increase its ability to absorb CO2.
An added benefit would be countering acidification. Again, there is a caveat. As a relatively new idea that hasn't been tested widely at scale, there are still significant questions about how these chemical changes would affect marine life.
That includes the plant-like phytoplankton that form the base of the marine food web and drive many of the ocean's most important biogeochemical processes. Steve Archer, a senior research scientist at Bigelow Laboratory for Ocean Sciences, is working with a team of researchers from around the world to help fill those knowledge gaps. Over the past five years, they've run several large-scale experiments using an isolated system called a mesocosm that replicates natural conditions without influencing the ocean directly.
These experiments are helping scientists understand the potential biological impacts and nuances of OAE, including its effect on plankton. "There are already companies proposing to do this, but they're going into it without sufficient information on what's going to happen," Archer said. "There are some important questions that we're trying to answer to ensure we have informed, science-based decision-making when it comes to OAE and marine carbon dioxide removal." OAE works on a rather basic principle.
Extract — continue reading at the source.
