An international group of scientists, including researchers from the Woods Hole Oceanographic Institution, are working to improve communication about ocean acidification to help the public better understand the pressing global issue.
The term “ocean acidification” (OA) describes the changes that occur in the ocean as a result of increased emissions of carbon dioxide (CO2) into the atmosphere. The rising acidic level in the ocean puts certain organisms at risk and threatens the overall health of the ocean. (more…)
Researchers at the UH Manoa School of Ocean and Earth Science and Technology (SOEST) made a discovery that challenges a major theory in the field of coral reef ecology.
The general assumption has been that the more flexible corals are, regarding which species of single-celled algae (Symbiodinium) they host in coral tissues, the greater ability corals will have to survive environmental stress. In their paper published August 29, 2012, however, scientists at the Hawaii Institute of Marine Biology (HIMB) at SOEST and colleagues documented that the more flexible corals are, the more sensitive to environment disturbances they are. (more…)
Scientists are setting sail on August 25 to study ocean acidification in the Arctic and what this means for the future survival of marine and terrestrial organisms.
The Arctic Ocean is one of the most vulnerable places on the planet for acidification, yet it is the least-explored ocean. Acidification can disturb the balance of marine life in the world’s oceans, and consequently affect humans and animals that rely on those food resources.
Ocean acidification is particularly harmful to organisms such as corals, oysters, crabs, shrimp and plankton, as well as those up and down the food chain. Higher acidity decreases an organism’s calcification rate, meaning they lose their ability to build shells or skeletons. (more…)
*Increase in ocean acidification led to collapse of oyster seed production at Oregon hatchery*
Marine researchers have definitively linked the collapse of oyster seed production at a commercial oyster hatchery in Oregon to an increase in ocean acidification.
Larval growth at the hatchery declined to a level considered by the owners to be “non-economically viable.”
A study by the scientists found that increased seawater carbon dioxide (CO2) levels, resulting in more corrosive ocean water, inhibited the larval oysters from developing their shells and growing at a pace that would make commercial production cost-effective. (more…)
*Few parallels for today’s rapid ocean changes in geologic record*
The oceans may be acidifying faster today than they did in the last 300 million years, according to scientists publishing a paper this week in the journal Science.
“What we’re doing today really stands out in the geologic record,” says lead author Bärbel Hönisch, a paleoceanographer at Columbia University’s Lamont-Doherty Earth Observatory. (more…)
Nearly one-third of CO2 emissions due to human activities enters the world’s oceans. By reacting with seawater, CO2 increases the water’s acidity, which may significantly reduce the calcification rate of such marine organisms as corals and mollusks, resulting in the potential loss of ecosystems. The extent to which human activities have raised the surface level of acidity, however, has been difficult to detect on regional scales because it varies naturally from one season and one year to the next, and between regions, and direct observations go back only 30 years.
By combining computer modeling with observations, an international team of scientists concluded that anthropogenic CO2 emissions, resulting from the influence of human beings, over the last 100 to 200 years have already raised ocean acidity far beyond the range of natural variations. The study is published in the January 22, 2012 online issue of Nature Climate Change. (more…)
Washington, D.C. — Coral reefs are extremely diverse ecosystems that support enormous biodiversity. But they are at risk. Carbon dioxide emissions are acidifying the ocean, threatening reefs and other marine organisms. New research led by Carnegie’s Kenneth Schneider analyzed the role of sea cucumbers in portions of the Great Barrier Reef and determined that their dietary process of dissolving calcium carbonate (CaCO3) from the surrounding reef accounts for about half of at the total nighttime dissolution for the reef. The work is published December 23 by the Journal of Geophysical Research.
Reefs are formed through the biological deposition of calcium carbonate (CaCO3). Many of the marine organisms living on and around a reef contribute to either its destruction or construction. Therefore it is crucial that the amount of calcium carbonate remain in balance. When this delicate balance is disrupted, the reef ceases to grow and its foundations can be weakened. (more…)
Changes in ocean chemistry due to increased carbon dioxide (CO2) emissions are expected to damage shellfish populations around the world, but some nations will feel the impacts much sooner and more intensely than others, according to a study by scientists at Woods Hole Oceanographic Institution (WHOI).
As CO2 levels driven by fossil fuel use have increased in the atmosphere since the Industrial Revolution, so has the amount of CO2 absorbed by the world’s oceans, leading to changes in the chemical make-up of seawater. Known as ocean acidification, this decrease in pH creates a corrosive environment for some marine organisms such as corals, marine plankton, and shellfish that build carbonate shells or skeletons. (more…)
