What is ocean acidification

Articles about ocean acidification PMEL carbon group frequently works with the media to inform t A pH unit is a measure of acidity ranging from The lower the value, the higher the acidity of the environment. A shift in pH to a lower value reflects an increase in acidity. When carbon dioxide CO 2 is absorbed by seawater, chemical reactions occur that reduce seawater pH, carbonate ion concentration, and saturation states of biologically important calcium carbonate minerals. These chemical reactions are termed "ocean acidification" or "OA" for short.

Calcium carbonate minerals are the building blocks for the skeletons and shells of many marine organisms. In areas where most life now congregates in the ocean, the seawater is supersaturated with respect to calcium carbonate minerals. This means there are abundant building blocks for calcifying organisms to build their skeletons and shells.

However, continued ocean acidification is causing many parts of the ocean to become undersaturated with these minerals, which is likely to affect the ability of some organisms to produce and maintain their shells. Since the beginning of the Industrial Revolution, the pH of surface ocean waters has fallen by 0. Since the pH scale, like the Richter scale, is logarithmic, this change represents approximately a 30 percent increase in acidity see our pH primer web page for more information.

Future predictions indicate that the oceans will continue to absorb carbon dioxide, further increasing ocean acidity.

Ocean acidification is expected to impact ocean species to varying degrees. Science , — Kheshgi, H. Sequestering atmospheric carbon-dioxide by increasing ocean alkalinity. Energy 20 , — Kleypas, J. Geochemical consequences of increased atmospheric carbon dioxide on coral reefs.

Luthi, D. High-resolution carbon dioxide concentration record ,, years before present. Nature , — Maier, C. Calcification of the cold-water coral Lophelia pertusa under ambient and reduced pH. Biogeosciences 6 , — Manzello, D. Poorly cemented coral reefs of the eastern tropical Pacific: Possible insights into reef development in a high—CO 2 world. Masson-Delmotte, V. Quaternary Science Reviews 29 , — Monnin, C. Orr, J. Anthropogenic ocean acidification over the twenty-first century and its impact on calcifying organisms.

Pandolfi, J. Projecting coral reef futures under global warming and ocean acidification. Petit, J. Climate and atmospheric history of the past , years from the Vostok ice core, Antarctica. Raven, J. Revelle, R. Carbon dioxide exchange between atmosphere and ocean and the question of an increase of atmospheric CO 2 during the past decades.

Tellus 9 , 18—27 Ridgwell, A. Past constraints on the vulnerability of marine calcifiers to massive carbon dioxide release. Nature Geoscience 3 , — From laboratory manipulations to Earth system models: Scaling calcification impacts of ocean acidification.

Biogeosciences 6 , Ries, J. Marine calcifiers exhibit mixed responses to CO 2 -induced ocean acidification. Geology 37 , — Sabine, C.

The oceanic sink for anthropogenic CO 2. Siegenthaler, U. Stable carbon cycle-climate relationship during the late Pleistocene. Turley, C. The societal challenge of ocean acidification. Marine Pollution Bulletin 60 , — Global Change: An Overview. Conservation of Biodiversity. Introduction to the Basic Drivers of Climate. Tropical Weather. Terrestrial Biomes. Can the offspring from these more resilient corals travel to other reefs to help sustain more vulnerable coral populations there?

Graduate student Hannah Barkley is on a mission to investigate how warming ocean temperatures, ocean acidification, and other impacts of climate change are affecting corals in an effort to find ways to preserve these vital ocean resources. A new study led by WHOI scientists shows how changing ocean conditions can combine to intensify erosion of coral reefs. The more hydrogen ions that are present,…. When carbon dioxide mixes with seawater it has the effect of reducing the availability of carbonate ions, which many marine….

Introduction Ocean acidification is a new field of research in which most studies have been published in the past 10…. He uses techniques that span isotope geochemistry, next generation DNA sequencing, and satellite tagging to study the ecology of a wide variety of ocean species.

He recently discovered that blue sharks use warm water ocean tunnels, or eddies, to dive to the ocean twilight zone, where they forage in nutrient-rich waters hundreds of meters down. Born in New Zealand, Simon received his B. With much of his work in the South Pacific and Caribbean, Simon has been on many cruises, logging 1, hours of scuba diving and hours in tropical environs. He has been a scientist at Woods Hole Oceanographic Institution since Gregory Skomal is an accomplished marine biologist, underwater explorer, photographer, and author.

He has been a fisheries scientist with the Massachusetts Division of Marine Fisheries since and currently heads up the Massachusetts Shark Research Program. For more than 30 years, Greg has been actively involved in the study of life history, ecology, and physiology of sharks.

His shark research has spanned the globe from the frigid waters of the Arctic Circle to coral reefs in the tropical Central Pacific. Much of his current research centers on the use of acoustic telemetry and satellite-based tagging technology to study the ecology and behavior of sharks.

He has written dozens of scientific research papers and has appeared in a number of film and television documentaries, including programs for National Geographic, Discovery Channel, BBC, and numerous television networks.

His most recent book, The Shark Handbook, is a must buy for all shark enthusiasts. Robert D. He served in the U. Navy for more than 30 years and continues to work with the Office of Naval Research. A pioneer in the development of deep-sea submersibles and remotely operated vehicle systems, he has taken part in more than deep-sea expeditions. In , he discovered the RMS Titanic , and has succeeded in tracking down numerous other significant shipwrecks, including the German battleship Bismarck , the lost fleet of Guadalcanal, the U.

He is known for his research on the ecology and evolution of fauna in deep-ocean hydrothermal, seamount, canyon and deep trench systems. He has conducted more than 60 scientific expeditions in the Arctic, Atlantic, Pacific, and Indian Oceans.

Sunita L. If greenhouse gas emissions continue as they are doing at present the RCP8. The acidification of the oceans will not be uniform worldwide. Polar seas, and upwelling regions, often found along the west coasts of continents, are expected to acidify faster than temperate or tropical regions.

The pH will vary significantly depending on the ecosystem. In some parts of the Arctic the water is acidic enough to corrode some types of shells and in California occasional corrosive events have already occurred.

Most surface waters will be continually corrosive within decades. Ocean acidification reduces the amount of carbonate, a key building block in seawater. This makes it more difficult for marine organisms, such as coral and some plankton, to form their shells and skeletons, and existing shells may begin to dissolve. The present-day pH of seawater is highly variable, and a single organism can cope with fluctuations of different pH levels during its lifetime.

The problem with ocean acidification is the sustained nature of the change, as the risk comes from the lifetime exposure to lower pH levels. The rapid pace of acidification will influence the extent to which calcifying organisms will be able to adapt.

The impacts of ocean acidification are not uniform across all species. Some algae and seagrass may benefit from higher CO 2 concentrations in the ocean, as they may increase their photosynthetic and growth rates.

However, a more acidic environment will harm other marine species such as molluscs, corals and some varieties of plankton Figure 4. The shells and skeletons of these animals may become less dense or strong.

In the case of coral reefs this may make them more vulnerable to storm damage and slow the recovery rate. Marine organisms could also experience changes in growth, development, abundance, and survival in response to ocean acidification Figure 5. Most species seem to be more vulnerable in their early life stages. Juvenile fish for example, may have trouble locating suitable habitat to live. Despite the different responses within and between marine groups, positive or negative, research suggests that ocean acidification will be a driver for substantial changes in ocean ecosystems this century.

These changes may be made worse by the combined effect with other emerging climate-related hazards, such as the decrease of ocean oxygen levels — a condition known as ocean deoxygenation —that is already affecting marine life in some regions Long et al.

Changes in marine ecosystems will have consequences for human societies, which depend on the goods and services these ecosystems provide. The implications for society could include substantial revenue declines, loss of employment and livelihoods, and other indirect economic costs. Socioeconomic impacts associated with the decline of the following ecosystem services are expected:.

While reducing global greenhouse gas emissions mitigation is the ultimate solution to ocean acidification, undertaking some challenging decisions and actions can help us prepare for the adverse effects of ocean acidification. This is the adaptation approach. At the local level, the following policy and management options can help to minimise the adverse effects of other local stressors and, as a result, help marine ecosystems to cope better with changing environmental conditions.

Bycatch is either of a different species, the wrong sex, or is undersized or juvenile individuals of the target species. Environmental management , 52 4 , Brown, C. Saunders, H. Possingham, and A.

Richardson, Managing for interactions between local and global stressors of ecosystems. PLoS One , 8 6. Feely, R. Sabine, and V. Fabry, Carbon Dioxide and our Ocean Legacy. Accessed 17 May Gattuso, J.

Brewer, O. Hoegh-Guldberg, J. Kleypas, H. Schmidt, Cross-chapter box on ocean acidification. Part A: Global and Sectoral Aspects.