"But once the carbon dioxide levels reach a certain threshold, their growth rates will stop increasing because they will have to divert more energy into calcification as opposed to growth and division. "In the last few decades, the increase in carbon dioxide has been differentially favoring coccolithophores because their photosynthetic (opens in new tab) system was not yet saturated, and that extra energy was translated into higher growth rates," said Sara Rivero-Calle, a researcher at the Center for Marine Science at the University of North Carolina, Wilmington. When coccolithophores die, their calcite husks sink to the seafloor, depositing carbon. The tiny algae are the primary calcifiers of our oceans and are important contributors to Earth's carbon cycle. Coccolithophores (opens in new tab) are known for the beautiful and intricate microscopic plates of armor they form from calcium carbonate, called coccoliths. These single-celled plant-like critters live in abundance in the upper layers of Earth's oceans, soaking up sunlight and carbon dioxide through photosynthesis. On the other hand, studies have shown that tiny, calcifying phytoplankton called coccolithophores are temporarily taking advantage of the changing climate. Studies (opens in new tab) have shown that increasing ocean acidification negatively impacts many coral species' ability to grow their calcium skeletons. Animals like corals, which are already threatened by rising ocean temperatures (opens in new tab), are especially at risk from ocean acidification. Threatening these species puts even greater numbers of marine life at risk, and in turn, the communities that rely on the ocean's once bountiful resources. Unfortunately, many of the organisms most sensitive to ocean acidification make up the base of the ecological food web in ocean environments. (Image credit: NOAA) (opens in new tab) What ocean acidification does to coral and other marine life Pteropods are an important food source for juvenile salmon off the Pacific Northwest coast of the United States.
The shell of a marine snell, called a pteropod, dissolves from an increase in the acidity of seawater.