Ocean acidification is the name given to the ongoing decrease in the
pHIn chemistry, pH is a measure of the acidity or basicity of an aqueous solution. Pure water is said to be neutral, with a pH close to 7.0 at . Solutions with a pH less than 7 are said to be acidic and solutions with a pH greater than 7 are basic or alkaline...
and increase in acidity of the Earth's
oceanAn ocean is a major body of saline water, and a principal component of the hydrosphere. Approximately 71% of the Earth's surface is covered by ocean, a continuous body of water that is customarily divided into several principal oceans and smaller seas.More than half of this area is over 3,000...
s, caused by the uptake of anthropogenic
carbon dioxideCarbon dioxide is a naturally occurring chemical compound composed of two oxygen atoms covalently bonded to a single carbon atom...
from the
atmosphereThe atmosphere of Earth is a layer of gases surrounding the planet Earth that is retained by Earth's gravity. The atmosphere protects life on Earth by absorbing ultraviolet solar radiation, warming the surface through heat retention , and reducing temperature extremes between day and night...
.
Generally speaking, when the carbon molecules in the air above seawater increase by four molecules, one will diffuse into seawater. About a quarter of the carbon dioxide in the atmosphere goes into the sea. As the amount of carbon rose in the atmosphere there was a corresponding rise of carbon going into the ocean.
When carbon dioxide is absorbed by seawater, chemical reactions occur that reduce seawater pH, carbonate ion concentration, and saturation states of biologically important
calcium carbonateCalcium carbonate is a chemical compound with the formula CaCO3. It is a common substance found in rocks in all parts of the world, and is the main component of shells of marine organisms, snails, coal balls, pearls, and eggshells. Calcium carbonate is the active ingredient in agricultural lime,...
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. Increasing acidity in sea water, pushing it towards soda water, increases the potential of calcium in animals to fizzle.
Between 1751 and 1994 surface ocean pH is estimated to have decreased from approximately 8.25 to 8.14, representing an increase of approaching 30% in "acidity" (
H+In chemistry, a hydron is the general name for a cationic form of atomic hydrogen : most commonly a "proton". However, hydron includes cations of hydrogen regardless of their isotopic composition: thus it refers collectively to protons , deuterons , and tritons...
ion concentration) in the world's oceans.
Carbon cycle
The
carbon cycleThe carbon cycle is the biogeochemical cycle by which carbon is exchanged among the biosphere, pedosphere, geosphere, hydrosphere, and atmosphere of the Earth...
describes the fluxes of carbon dioxide between the oceans,
terrestrialEarth is the third planet from the Sun, and the densest and fifth-largest of the eight planets in the Solar System. It is also the largest of the Solar System's four terrestrial planets...
biosphereThe biosphere is the global sum of all ecosystems. It can also be called the zone of life on Earth, a closed and self-regulating system...
,
lithosphereThe lithosphere is the rigid outermost shell of a rocky planet. On Earth, it comprises the crust and the portion of the upper mantle that behaves elastically on time scales of thousands of years or greater.- Earth's lithosphere :...
, and the
atmosphereAn atmosphere is a layer of gases that may surround a material body of sufficient mass, and that is held in place by the gravity of the body. An atmosphere may be retained for a longer duration, if the gravity is high and the atmosphere's temperature is low...
. Human activities such as the
combustionCombustion or burning is the sequence of exothermic chemical reactions between a fuel and an oxidant accompanied by the production of heat and conversion of chemical species. The release of heat can result in the production of light in the form of either glowing or a flame...
of
fossil fuelFossil fuels are fuels formed by natural processes such as anaerobic decomposition of buried dead organisms. The age of the organisms and their resulting fossil fuels is typically millions of years, and sometimes exceeds 650 million years...
s and
land useLand use is the human use of land. Land use involves the management and modification of natural environment or wilderness into built environment such as fields, pastures, and settlements. It has also been defined as "the arrangements, activities and inputs people undertake in a certain land cover...
changes have led to a new flux of into the atmosphere. About 45% has remained in the atmosphere; most of the rest has been taken up by the oceans, with some also taken up by terrestrial
plantPlants are living organisms belonging to the kingdom Plantae. Precise definitions of the kingdom vary, but as the term is used here, plants include familiar organisms such as trees, flowers, herbs, bushes, grasses, vines, ferns, mosses, and green algae. The group is also called green plants or...
s.
The carbon cycle involves both
organic compoundAn organic compound is any member of a large class of gaseous, liquid, or solid chemical compounds whose molecules contain carbon. For historical reasons discussed below, a few types of carbon-containing compounds such as carbides, carbonates, simple oxides of carbon, and cyanides, as well as the...
s as well as inorganic carbon compounds such as
carbon dioxideCarbon dioxide is a naturally occurring chemical compound composed of two oxygen atoms covalently bonded to a single carbon atom...
and the
carbonateIn chemistry, a carbonate is a salt of carbonic acid, characterized by the presence of the carbonate ion, . The name may also mean an ester of carbonic acid, an organic compound containing the carbonate group C2....
s. The inorganic compounds are particularly relevant when discussing ocean acidification for it includes the many forms of dissolved present in the Earth's oceans.
When dissolves, it reacts with water to form a balance of
ionAn ion is an atom or molecule in which the total number of electrons is not equal to the total number of protons, giving it a net positive or negative electrical charge. The name was given by physicist Michael Faraday for the substances that allow a current to pass between electrodes in a...
ic and non-ionic chemical species: dissolved free carbon dioxide ,
carbonic acidCarbonic acid is the inorganic compound with the formula H2CO3 . It is also a name sometimes given to solutions of carbon dioxide in water, because such solutions contain small amounts of H2CO3. Carbonic acid forms two kinds of salts, the carbonates and the bicarbonates...
,
bicarbonateIn inorganic chemistry, bicarbonate is an intermediate form in the deprotonation of carbonic acid...
and
carbonateIn chemistry, a carbonate is a salt of carbonic acid, characterized by the presence of the carbonate ion, . The name may also mean an ester of carbonic acid, an organic compound containing the carbonate group C2....
. The ratio of these species depends on factors such as
seawaterSeawater is water from a sea or ocean. On average, seawater in the world's oceans has a salinity of about 3.5% . This means that every kilogram of seawater has approximately of dissolved salts . The average density of seawater at the ocean surface is 1.025 g/ml...
temperatureTemperature is a physical property of matter that quantitatively expresses the common notions of hot and cold. Objects of low temperature are cold, while various degrees of higher temperatures are referred to as warm or hot...
and
alkalinityAlkalinity or AT measures the ability of a solution to neutralize acids to the equivalence point of carbonate or bicarbonate. The alkalinity is equal to the stoichiometric sum of the bases in solution...
(see the article on the ocean's
solubility pumpIn oceanic biogeochemistry, the solubility pump is a physico-chemical process that transports carbon from the ocean's surface to its interior.-Overview:...
for more detail).
Acidification
Dissolving in seawater increases the
hydrogenHydrogen is the chemical element with atomic number 1. It is represented by the symbol H. With an average atomic weight of , hydrogen is the lightest and most abundant chemical element, constituting roughly 75% of the Universe's chemical elemental mass. Stars in the main sequence are mainly...
ion concentration in the ocean, and thus decreases ocean pH.
CaldeiraKen Caldeira is an atmospheric scientist who works at the Carnegie Institution for Science's . He researches ocean acidification, climate effects of trees, intentional climate modification, and interactions in the global Carbon cycle/climate system...
and Wickett (2003) placed the rate and magnitude of modern ocean acidification changes in the context of probable historical changes during the last 300 million years.
Average surface ocean pH
| Time |
pH |
pH change |
Source |
H+ concentration change
relative to pre-industrial |
| Pre-industrial (18th century) |
8.179 |
0.000 |
analysed field |
0% |
| Recent past (1990s) |
8.104 |
−0.075 |
field |
+ 18.9% |
| Present levels |
~8.069 |
−0.11 |
field |
+ 28.8% |
| 2050 (2× = 560 ppm) |
7.949 |
−0.230 |
model |
+ 69.8% |
| 2100 (IS92a) |
7.824 |
−0.355 |
model |
+ 126.5% |
Since the
industrial revolutionThe Industrial Revolution was a period from the 18th to the 19th century where major changes in agriculture, manufacturing, mining, transportation, and technology had a profound effect on the social, economic and cultural conditions of the times...
began, it is estimated that surface ocean pH has dropped by slightly more than 0.1 units on the
logarithmThe logarithm of a number is the exponent by which another fixed value, the base, has to be raised to produce that number. For example, the logarithm of 1000 to base 10 is 3, because 1000 is 10 to the power 3: More generally, if x = by, then y is the logarithm of x to base b, and is written...
ic scale of pH, representing an approximately 29% increase in , and it is estimated that it will drop by a further 0.3 to 0.5 pH units (an additional doubling to tripling of today's
post-industrialIf a nation becomes "post-industrial" it passes through, or dodges, a phase of society predominated by a manufacturing-based economy and moves on to a structure of society based on the provision of information, innovation, finance, and services.-Characteristics:...
acid concentrations) by 2100 as the oceans absorb more anthropogenic . These changes are predicted to continue rapidly as the oceans take up more anthropogenic from the atmosphere. The degree of change to ocean chemistry, including ocean pH, will depend on the mitigation and emissions pathways society takes. Even though the ocean is acidifying, its pH is still greater than 7 (that of neutral
waterWater is a chemical substance with the chemical formula H2O. A water molecule contains one oxygen and two hydrogen atoms connected by covalent bonds. Water is a liquid at ambient conditions, but it often co-exists on Earth with its solid state, ice, and gaseous state . Water also exists in a...
), so the ocean could also be described as becoming less
basicFor the term in genetics, see base A base in chemistry is a substance that can accept hydrogen ions or more generally, donate electron pairs. A soluble base is referred to as an alkali if it contains and releases hydroxide ions quantitatively...
.
Although the largest changes are expected in the future, a report from NOAA scientists found large quantities of water undersaturated in
aragoniteAragonite is a carbonate mineral, one of the two common, naturally occurring, crystal forms of calcium carbonate, CaCO3...
are already upwelling close to the Pacific
continental shelfThe continental shelf is the extended perimeter of each continent and associated coastal plain. Much of the shelf was exposed during glacial periods, but is now submerged under relatively shallow seas and gulfs, and was similarly submerged during other interglacial periods. The continental margin,...
area of North America. Continental shelves play an important role in marine ecosystems since most marine organisms live or are
spawnedSpawn refers to the eggs and sperm released or deposited, usually into water, by aquatic animals. As a verb, spawn refers to the process of releasing the eggs and sperm, also called spawning...
there, and though the study only dealt with the area from
VancouverVancouver is a coastal seaport city on the mainland of British Columbia, Canada. It is the hub of Greater Vancouver, which, with over 2.3 million residents, is the third most populous metropolitan area in the country,...
to
northern CaliforniaNorthern California is the northern portion of the U.S. state of California. The San Francisco Bay Area , and Sacramento as well as its metropolitan area are the main population centers...
, the authors suggest that other shelf areas may be experiencing similar effects.
Rate
Similarly, one of the first detailed datasets examining temporal variations in pH at a temperate
coastA coastline or seashore is the area where land meets the sea or ocean. A precise line that can be called a coastline cannot be determined due to the dynamic nature of tides. The term "coastal zone" can be used instead, which is a spatial zone where interaction of the sea and land processes occurs...
al location found that acidification was occurring at a rate much higher than that previously predicted, with consequences for near-shore benthic ecosystems.
Thomas LovejoyDr. Thomas Eugene Lovejoy III is chief biodiversity adviser to the president of the World Bank, senior adviser to the president of the United Nations Foundation, and president of the Heinz Center for Science,...
,
former chief biodiversity advisor to the World Bank, has suggested that "the acidity of the oceans will more than double in the next 40 years. This rate is 100 times faster than any changes in ocean acidity in the last 20 million years, making it unlikely that marine life can somehow adapt to the changes."
Current rates of ocean acidification have been compared with the greenhouse event at the Paleocene-Eocene boundary (about 55 million years ago) when surface ocean temperatures rose by 5–6 degrees
CelsiusCelsius is a scale and unit of measurement for temperature. It is named after the Swedish astronomer Anders Celsius , who developed a similar temperature scale two years before his death...
. No catastrophe was seen in surface ecosystems, yet bottom-dwelling organisms in the deep ocean experienced a major extinction. The current acidification is on a path to reach levels higher than any seen in the last 65 million years, and the rate of increase is about ten times the rate that preceded Paleocene-Eocene mass extinction. The current and projected acidification has been described as an almost unprecedented geological event. A National Research Council study released in April 2010 likewise concluded that "the level of acid in the oceans is increasing at an unprecedented rate."
A review by climate scientists at the RealClimate blog, of a 2005 report by the Royal Society of the UK similarly highlighted the centrality of the
rates of change in the present anthropogenic acidification process, writing:
"The natural pH of the ocean is determined by a need to balance the deposition and burial of on the sea floor against the influx of and into the ocean from dissolving rocks on land, called weathering. These processes stabilize the pH of the ocean, by a mechanism called compensation...The point of bringing it up again is to note that if the concentration of the atmosphere changes more slowly than this, as it always has throughout the Vostok record, the pH of the ocean will be relatively unaffected because compensation can keep up. The [present] fossil fuel acidification is much faster than natural changes, and so the acid spike will be more intense than the earth has seen in at least 800,000 years."
A July 2010 article in Scientific American quoted marine geologist William Howard of the Antarctic Climate and Ecosystems Cooperative Research Center in
HobartHobart is the state capital and most populous city of the Australian island state of Tasmania. Founded in 1804 as a penal colony,Hobart is Australia's second oldest capital city after Sydney. In 2009, the city had a greater area population of approximately 212,019. A resident of Hobart is known as...
, Tasmania stating that "the current rate of ocean acidification is about a hundred times faster than the most rapid events" in the geologic past. Research at the University of South Florida has shown that in the 15-year period 1995–2010 alone, acidity has increased 6 percent in the upper 100 meters of the Pacific Ocean from Hawaii to Alaska.
Calcification
Changes in ocean chemistry can have extensive direct and indirect effects on organisms and their habitats. One of the most important repercussions of increasing ocean acidity relates to the production of shells and plates out of calcium carbonate . This process is called calcification and is important to the biology and survival of a wide range of marine organisms. Calcification involves the
precipitationPrecipitation is the formation of a solid in a solution or inside anothersolid during a chemical reaction or by diffusion in a solid. When the reaction occurs in a liquid, the solid formed is called the precipitate, or when compacted by a centrifuge, a pellet. The liquid remaining above the solid...
of dissolved ions into solid structures, such as
coccolithCoccoliths are individual plates of calcium carbonate formed by coccolithophores which are arranged around them in a coccosphere.- Formation and composition :...
s. After they are formed, such structures are vulnerable to
dissolutionDissolution is the process by which a solid, liquid or gas forms a solution in a solvent. In solids this can be explained as the breakdown of the crystal lattice into individual ions, atoms or molecules and their transport into the solvent. For liquids and gases, the molecules must be compatible...
unless the surrounding seawater contains
saturatingIn chemistry, saturation has six different meanings, all based on reaching a maximum capacity...
concentrations of carbonate ions. The
saturationIn chemistry, saturation has six different meanings, all based on reaching a maximum capacity...
state of seawater for a mineral (known as Ω) is a measure of the thermodynamic potential for the mineral to form or to dissolve, and is described by the following equation:
Here Ω is the product of the concentrations (or
activitiesIn chemical thermodynamics, activity is a measure of the “effective concentration” of a species in a mixture, meaning that the species' chemical potential depends on the activity of a real solution in the same way that it would depend on concentration for an ideal solution.By convention, activity...
) of the reacting ions that form the mineral ( and ), divided by the product of the concentrations of those ions when the mineral is at
equilibriumIn a chemical reaction, chemical equilibrium is the state in which the concentrations of the reactants and products have not yet changed with time. It occurs only in reversible reactions, and not in irreversible reactions. Usually, this state results when the forward reaction proceeds at the same...
, that is, when the mineral is neither forming nor dissolving. In seawater, a natural horizontal boundary is formed as a result of temperature, pressure, and depth, and is known as the saturation horizon, or
lysoclineThe lysocline is a term used in geology, geochemistry and marine biology to denote the depth in the ocean below which the rate of dissolution of calcite increases dramatically....
. Above this saturation horizon, Ω has a value greater than 1, and does not readily dissolve. Most calcifying organisms live in such waters. Below this depth, Ω has a value less than 1, and will dissolve. However, if its production rate is high enough to offset dissolution, can still occur where Ω is less than 1. The
carbonate compensation depthCalcite compensation depth is the depth in the oceans below which the rate of supply of calcite lags behind the rate of solvation, such that no calcite is preserved. Aragonite compensation depth describes the same behaviour in reference to aragonitic carbonates.Calcium carbonate is essentially...
occurs at the depth in the ocean where production is exceeded by dissolution.
Calcium carbonate occurs in two common
polymorphsPolymorphism in materials science is the ability of a solid material to exist in more than one form or crystal structure. Polymorphism can potentially be found in any crystalline material including polymers, minerals, and metals, and is related to allotropy, which refers to chemical elements...
:
aragoniteAragonite is a carbonate mineral, one of the two common, naturally occurring, crystal forms of calcium carbonate, CaCO3...
and
calciteCalcite is a carbonate mineral and the most stable polymorph of calcium carbonate . The other polymorphs are the minerals aragonite and vaterite. Aragonite will change to calcite at 380-470°C, and vaterite is even less stable.-Properties:...
. Aragonite is much more soluble than calcite, with the result that the aragonite saturation horizon is always nearer to the surface than the calcite saturation horizon. This also means that those organisms that produce aragonite may possibly be more vulnerable to changes in ocean acidity than those that produce calcite. Increasing levels and the resulting lower pH of seawater decreases the saturation state of and raises the saturation horizons of both forms closer to the surface. This decrease in saturation state is believed to be one of the main factors leading to decreased calcification in marine organisms, as it has been found that the inorganic precipitation of is directly proportional to its saturation state.
Possible impacts
Although the
natural absorption of In oceanic biogeochemistry, the solubility pump is a physico-chemical process that transports carbon from the ocean's surface to its interior.-Overview:...
by the world's oceans helps mitigate the
climaticClimate change is a significant and lasting change in the statistical distribution of weather patterns over periods ranging from decades to millions of years. It may be a change in average weather conditions or the distribution of events around that average...
effects of anthropogenic emissions of , it is believed that the resulting decrease in pH will have negative consequences, primarily for oceanic
calcifyingCalcification is the process in which calcium salts build up in soft tissue, causing it to harden. Calcifications may be classified on whether there is mineral balance or not, and the location of the calcification.-Causes:...
organisms. These span the
food chainA food web depicts feeding connections in an ecological community. Ecologists can broadly lump all life forms into one of two categories called trophic levels: 1) the autotrophs, and 2) the heterotrophs...
from
autotrophAn autotroph, or producer, is an organism that produces complex organic compounds from simple inorganic molecules using energy from light or inorganic chemical reactions . They are the producers in a food chain, such as plants on land or algae in water...
s to
heterotrophA heterotroph is an organism that cannot fix carbon and uses organic carbon for growth. This contrasts with autotrophs, such as plants and algae, which can use energy from sunlight or inorganic compounds to produce organic compounds such as carbohydrates, fats, and proteins from inorganic carbon...
s and include organisms such as
coccolithophoreCoccolithophores are single-celled algae, protists, and phytoplankton belonging to the division of haptophytes. They are distinguished by special calcium carbonate plates of uncertain function called coccoliths , which are important microfossils...
s,
coralCorals are marine animals in class Anthozoa of phylum Cnidaria typically living in compact colonies of many identical individual "polyps". The group includes the important reef builders that inhabit tropical oceans and secrete calcium carbonate to form a hard skeleton.A coral "head" is a colony of...
s,
foraminiferaThe Foraminifera , or forams for short, are a large group of amoeboid protists which are among the commonest plankton species. They have reticulating pseudopods, fine strands of cytoplasm that branch and merge to form a dynamic net...
,
echinodermEchinoderms are a phylum of marine animals. Echinoderms are found at every ocean depth, from the intertidal zone to the abyssal zone....
s, crustaceans and
molluscsThe Mollusca , common name molluscs or mollusksSpelled mollusks in the USA, see reasons given in Rosenberg's ; for the spelling mollusc see the reasons given by , is a large phylum of invertebrate animals. There are around 85,000 recognized extant species of molluscs. Mollusca is the largest...
. As described above, under normal conditions, calcite and aragonite are stable in surface waters since the carbonate ion is at
supersaturatingThe term supersaturation refers to a solution that contains more of the dissolved material than could be dissolved by the solvent under normal circumstances...
concentrations. However, as ocean pH falls, so does the concentration of this ion, and when carbonate becomes undersaturated, structures made of calcium carbonate are vulnerable to dissolution. Even if there is no change in the rate of calcification, therefore, the rate of dissolution of calcareous material increases.
Research has already found that corals, coccolithophore algae, coralline algae, foraminifera,
shellfishShellfish is a culinary and fisheries term for exoskeleton-bearing aquatic invertebrates used as food, including various species of molluscs, crustaceans, and echinoderms. Although most kinds of shellfish are harvested from saltwater environments, some kinds are found only in freshwater...
and pteropods experience reduced calcification or enhanced dissolution when exposed to elevated .
The
Royal Society of LondonThe Royal Society of London for Improving Natural Knowledge, known simply as the Royal Society, is a learned society for science, and is possibly the oldest such society in existence. Founded in November 1660, it was granted a Royal Charter by King Charles II as the "Royal Society of London"...
published a comprehensive overview of ocean acidification, and its potential consequences, in June 2005. However, some studies have found different response to ocean acidification, with coccolithophore calcification and photosynthesis both increasing under elevated atmospheric p, an equal decline in primary production and calcification in response to elevated or the direction of the response varying between species. Recent work examining a
sediment coreSedimentology encompasses the study of modern sediments such as sand, mud , and clay, and the processes that result in their deposition. Sedimentologists apply their understanding of modern processes to interpret geologic history through observations of sedimentary rocks and sedimentary...
from the
North AtlanticThe Atlantic Ocean is the second-largest of the world's oceanic divisions. With a total area of about , it covers approximately 20% of the Earth's surface and about 26% of its water surface area...
found that while the species composition of coccolithophorids has remained unchanged for the
industrialThe Industrial Revolution was a period from the 18th to the 19th century where major changes in agriculture, manufacturing, mining, transportation, and technology had a profound effect on the social, economic and cultural conditions of the times...
period 1780 to 2004, the calcification of coccoliths has increased by up to 40% during the same time. While the full
ecologicalEcology is the scientific study of the relations that living organisms have with respect to each other and their natural environment. Variables of interest to ecologists include the composition, distribution, amount , number, and changing states of organisms within and among ecosystems...
consequences of these changes in calcification are still uncertain, it appears likely that many calcifying species will be adversely affected.
When exposed in experiments to pH reduced by 0.2 to 0.4, larvae of a temperate brittlestar, a relative of the common sea star, fewer than 0.1 percent survived more than eight days. There is also a suggestion that a decline in the coccolithophores may have secondary effects on climate, contributing to
global warmingGlobal warming refers to the rising average temperature of Earth's atmosphere and oceans and its projected continuation. In the last 100 years, Earth's average surface temperature increased by about with about two thirds of the increase occurring over just the last three decades...
by decreasing the Earth's
albedoAlbedo , or reflection coefficient, is the diffuse reflectivity or reflecting power of a surface. It is defined as the ratio of reflected radiation from the surface to incident radiation upon it...
via their effects on
oceanic cloud coverThe CLAW hypothesis proposes a feedback loop that operates between ocean ecosystems and the Earth's climate. The hypothesis specifically proposes that particular phytoplankton that produce dimethyl sulfide are responsive to variations in climate forcing, and that these responses lead to a negative...
.
Aside from calcification, organisms may suffer other adverse effects, either directly as reproductive or physiological effects (e.g. -induced acidification of body fluids, known as
hypercapniaHypercapnia or hypercapnea , also known as hypercarbia, is a condition where there is too much carbon dioxide in the blood...
), or indirectly through negative impacts on food resources. Ocean acidification may also force some organisms to reallocate resources away from productive endpoints such as growth in order to maintain calcification. It has even been suggested that ocean acidification will alter the
acousticAcoustics is the interdisciplinary science that deals with the study of all mechanical waves in gases, liquids, and solids including vibration, sound, ultrasound and infrasound. A scientist who works in the field of acoustics is an acoustician while someone working in the field of acoustics...
properties of seawater, allowing sound to propagate further, increasing ocean noise and impacting animals that use sound for
echolocationEcholocation, also called biosonar, is the biological sonar used by several kinds of animals.Echolocating animals emit calls out to the environment and listen to the echoes of those calls that return from various objects near them. They use these echoes to locate and identify the objects...
or
communicationWhale sounds are the sounds made by whales and which are used for different kinds of communication.The word "song" is used to describe the pattern of regular and predictable sounds made by some species of whales, notably the Humpback Whale...
. However, as with calcification, as yet there is not a full understanding of these processes in marine organisms or
ecosystemAn ecosystem is a biological environment consisting of all the organisms living in a particular area, as well as all the nonliving , physical components of the environment with which the organisms interact, such as air, soil, water and sunlight....
s.
Leaving aside direct biological effects, it is expected that ocean acidification in the future will lead to a significant decrease in the burial of carbonate sediments for several centuries, and even the dissolution of existing carbonate sediments. This will cause an elevation of ocean
alkalinityAlkalinity or AT measures the ability of a solution to neutralize acids to the equivalence point of carbonate or bicarbonate. The alkalinity is equal to the stoichiometric sum of the bases in solution...
, leading to the enhancement of the ocean as a reservoir for with moderate (and potentially beneficial) implications for climate change as more leaves the atmosphere for the ocean.
See also
- Biological pump
In oceanic biogeochemistry, the biological pump is the sum of a suite of biologically-mediated processes that transport carbon from the surface euphotic zone to the ocean's interior.-Overview:...
- Carbon dioxide sinks
- Carbonate compensation depth
Calcite compensation depth is the depth in the oceans below which the rate of supply of calcite lags behind the rate of solvation, such that no calcite is preserved. Aragonite compensation depth describes the same behaviour in reference to aragonitic carbonates.Calcium carbonate is essentially...
- Continental shelf pump
In oceanic biogeochemistry, the continental shelf pump is proposed to operate in the shallow waters of the continental shelves, acting as a mechanism to transport carbon from surface waters to the interior of the adjacent deep ocean.-Overview:Originally formulated by Tsunogai et al. , the pump is...
- Greenhouse Gas
A greenhouse gas is a gas in an atmosphere that absorbs and emits radiation within the thermal infrared range. This process is the fundamental cause of the greenhouse effect. The primary greenhouse gases in the Earth's atmosphere are water vapor, carbon dioxide, methane, nitrous oxide, and ozone...
- Global Ocean Data Analysis Project
The Global Ocean Data Analysis Project is a synthesis project bringing together oceanographic data collected during the 1990s by research cruises on the World Ocean Circulation Experiment , Joint Global Ocean Flux Study and Ocean-Atmosphere Exchange Study programmes...
- Paleocene–Eocene Thermal Maximum
- Seawater pH
- Solubility pump
In oceanic biogeochemistry, the solubility pump is a physico-chemical process that transports carbon from the ocean's surface to its interior.-Overview:...
Further reading
- Antarctic Climate and Ecosystems Cooperative Research Centre (ACE CRC) (2008). Position analysis: CO2 emissions and climate change: OCEAN impacts and adaptation issues. ISSN: 1835–7911. Hobart, Tasmania. World|url=http://www.ipsl.jussieu.fr/~jomce/pubs/Cicerone_etal_2004_EOS.pdf|journal=EOS, Transactions American Geophysical Union
The American Geophysical Union is a nonprofit organization of geophysicists, consisting of over 50,000 members from over 135 countries. AGU's activities are focused on the organization and dissemination of scientific information in the interdisciplinary and international field of geophysics...
|volume=85|issue=37|pages=351–353|doi=10.1029/2004EO370007|bibcode=2004EOSTr..85R.351C}}, (Article preview only). on the System in the Oceans|url=http://www.sciencemag.org/cgi/content/abstract/sci;305/5682/362|journal=ScienceScience is the academic journal of the American Association for the Advancement of Science and is one of the world's top scientific journals....
|volume=305|issue=5682|pages=362–366|doi=10.1126/science.1097329|pmid=15256664}}
- Kleypas, J.A., R.A. Feely, V.J. Fabry, C. Langdon, C.L. Sabine, and L.L. Robbins. (2006). Impacts of Ocean Acidification on Coral Reefs and Other Marine Calcifiers: A Guide for Further Research, report of a workshop held 18–20 April 2005, St. Petersburg, FL, sponsored by National Science Foundation
The National Science Foundation is a United States government agency that supports fundamental research and education in all the non-medical fields of science and engineering. Its medical counterpart is the National Institutes of Health...
, NOAA and the U.S. Geological Survey, 88pp.
- Riebesell, U., V. J. Fabry, L. Hansson & J.-P. Gattuso (Eds.). (2010). Guide to best practices for ocean acidification research and data reporting, 260 p. Luxembourg: Publications Office of the European Union.
|url=http://www.sciencemag.org/cgi/content/abstract/305/5682/367|journal=Science|volume=305|issue=5682|pages=367–371|doi=10.1126/science.1097403|pmid=15256665}}
External links
Scientific sources:
- How Acidification Threatens Oceans from the Inside Out Scientific American
Scientific American is a popular science magazine. It is notable for its long history of presenting science monthly to an educated but not necessarily scientific public, through its careful attention to the clarity of its text as well as the quality of its specially commissioned color graphics...
August 9, 2010 by Marah J. Hardt and Carl SafinaCarl Safina is president and co-founder of the , and author of several writings on marine ecology and the ocean, including the award winning and .-Biography:...
- Ocean acidification due to increasing atmospheric carbon dioxide, report by the Royal Society
The Royal Society of London for Improving Natural Knowledge, known simply as the Royal Society, is a learned society for science, and is possibly the oldest such society in existence. Founded in November 1660, it was granted a Royal Charter by King Charles II as the "Royal Society of London"...
(UK)
- AR4 WG1 Chapter 5: Oceanic Climate Change and Sea Level, IPCC
The Intergovernmental Panel on Climate Change is a scientific intergovernmental body which provides comprehensive assessments of current scientific, technical and socio-economic information worldwide about the risk of climate change caused by human activity, its potential environmental and...
- State of the Science FACT SHEET: Ocean acidification, NOAA
The National Oceanic and Atmospheric Administration , pronounced , like "noah", is a scientific agency within the United States Department of Commerce focused on the conditions of the oceans and the atmosphere...
- Carbon Dioxide Information Analysis Center (CDIAC), the primary data analysis center of the U.S. Department of Energy
The United States Department of Energy is a Cabinet-level department of the United States government concerned with the United States' policies regarding energy and safety in handling nuclear material...
(located at Oak Ridge National LaboratoryOak Ridge National Laboratory is a multiprogram science and technology national laboratory managed for the United States Department of Energy by UT-Battelle. ORNL is the DOE's largest science and energy laboratory. ORNL is located in Oak Ridge, Tennessee, near Knoxville...
)
- Ocean acidification introduction, USGS
The United States Geological Survey is a scientific agency of the United States government. The scientists of the USGS study the landscape of the United States, its natural resources, and the natural hazards that threaten it. The organization has four major science disciplines, concerning biology,...
- Climate change threatening the Southern Ocean, report by CSIRO
The Commonwealth Scientific and Industrial Research Organisation is the national government body for scientific research in Australia...
- The Ocean in a High World, an international science symposium series
- The Acid Ocean – the Other Problem with Emission, David Archer (scientist)
David Archer is a computational ocean chemist, and has been a Professor at the Department of The Geophysical Sciences at the University of Chicago since 1993. He has published research on the carbon cycle of the ocean and the sea floor...
, a RealClimateRealClimate is a commentary site on climatology. The site's contributors are a group of climate scientists whose goal is to provide a quick response to developing stories and providing the context sometimes missing in mainstream commentary. The discussion is intended to be restricted to scientific...
discussion
- Regularly updated "blog" of ocean acidification publications and news, Jean-Pierre Gattuso
- Task Force on Ocean Acidification in the Pacific, including recent presentations on ocean acidification, Pacific Science Association
The Pacific Science Association is a regional, non-governmental, scholarly organization that seeks to advance science and technology in support of sustainable development in the Pacific Rim...
- Ocean Acidification, a multimedia, interactive site from The World Ocean Observatory
- Acidic Oceans: Why should we care? Perspectives in ocean science, Andrew Dickson, Scripps Institution of Oceanography
Scripps Institution of Oceanography in La Jolla, California, is one of the oldest and largest centers for ocean and earth science research, graduate training, and public service in the world...
- Climate Change: Coral Reefs on the Edge A video presentation by Prof. Ove Hoegh-Guldberg
Ove Hoegh-Guldberg , is the inaugural Director of the at the University of Queensland, and the holder of a Queensland Smart State Premier fellowship . He is best known for his work on climate change and coral reefs...
on impact of ocean acidification on coral reefs
- Ocean acidification virtual lab
- Ocean Acidification: Starting with the Science, a booklet from the Division on Earth & Life Studies of the United States National Research Council
The National Research Council of the USA is the working arm of the United States National Academies, carrying out most of the studies done in their names.The National Academies include:* National Academy of Sciences...
(released April 2011)
- Ocean Acidification, a United States National Academy of Sciences
The National Academy of Sciences is a corporation in the United States whose members serve pro bono as "advisers to the nation on science, engineering, and medicine." As a national academy, new members of the organization are elected annually by current members, based on their distinguished and...
/ National Research Council website that includes downloadable figures and interviews with ocean scientists
Scientific projects:
- Dr. Francisco Chavez on Ocean Acidification – Smithsonian Ocean Portal
- European Project of Ocean Acidification (EPOCA), a 4-year-long EU
The European Union is an economic and political union of 27 independent member states which are located primarily in Europe. The EU traces its origins from the European Coal and Steel Community and the European Economic Community , formed by six countries in 1958...
initiative to investigate ocean acidification (initiated June 2008)
- Biological Impacts of Ocean Acidification (BIOACID), a German
Germany , officially the Federal Republic of Germany , is a federal parliamentary republic in Europe. The country consists of 16 states while the capital and largest city is Berlin. Germany covers an area of 357,021 km2 and has a largely temperate seasonal climate...
initiative funded by BMBF
- Ocean Acidification Research Programme (UKOARP), a 5-year-long UK
The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...
initiative funded by NERCThe Natural Environment Research Council is a British research council that supports research, training and knowledge transfer activities in the environmental sciences.-History:...
, DefraThe Department for Environment, Food and Rural Affairs is the government department responsible for environmental protection, food production and standards, agriculture, fisheries and rural communities in the United Kingdom...
and DECCThe Department of Energy and Climate Change is a British government department created on 3 October 2008 by Prime Minister Gordon Brown to take over some of the functions of the Department for Business, Enterprise and Regulatory Reform and Department for Environment, Food and Rural Affairs...
- Research Program on Ocean Acidification at the Cluster of Excellence "Future Ocean", Kiel
Kiel is the capital and most populous city in the northern German state of Schleswig-Holstein, with a population of 238,049 .Kiel is approximately north of Hamburg. Due to its geographic location in the north of Germany, the southeast of the Jutland peninsula, and the southwestern shore of the...
- Ocean Acidification Research Center at University of Alaska Fairbanks
The University of Alaska Fairbanks, located in Fairbanks, Alaska, USA, is the flagship campus of the University of Alaska System, and is abbreviated as Alaska or UAF....
Popular media sources:
- Threatening Oceans from the Inside Out: How Acidification Affects Marine Life, Scientific American
Scientific American is a popular science magazine. It is notable for its long history of presenting science monthly to an educated but not necessarily scientific public, through its careful attention to the clarity of its text as well as the quality of its specially commissioned color graphics...
- "The Darkening Sea, article in The New Yorker magazine, Nov. 20, 2006 (requires registration)
- "Growing Acidity of Oceans May Kill Corals", Washington Post
- "Scientists Grapple with Ocean Acidification", ABC News
ABC News is the news gathering and broadcasting division of American broadcast television network ABC, a subsidiary of The Walt Disney Company...
- "Ocean Acidification & Climate", by Clayton Sandell ABC News
ABC News is the news gathering and broadcasting division of American broadcast television network ABC, a subsidiary of The Walt Disney Company...
- A World Without Whales? by Philippe Cousteau
Philippe Cousteau was a documentary film maker specializing in environmental issues, with a background in oceanography. He was the second son of Jacques-Yves Cousteau and Simone Cousteau....
, The Huffington PostThe Huffington Post is an American news website and content-aggregating blog founded by Arianna Huffington, Kenneth Lerer, and Jonah Peretti, featuring liberal minded columnists and various news sources. The site offers coverage of politics, theology, media, business, entertainment, living, style,...
- Acid Test: Can we save our oceans from ?, Oceana
Oceana is the largest international ocean conservation and advocacy organization. Oceana works to protect and restore the world’s oceans through targeted policy campaigns....
- The Acid Ocean, Stanford University
The Leland Stanford Junior University, commonly referred to as Stanford University or Stanford, is a private research university on an campus located near Palo Alto, California. It is situated in the northwestern Santa Clara Valley on the San Francisco Peninsula, approximately northwest of San...
Videos on Ocean Acidification:
- The Other Problem, an EPOCA-commissioned educational animation created by students from Ridgeway School, Plymouth
Plymouth is a city and unitary authority area on the coast of Devon, England, about south-west of London. It is built between the mouths of the rivers Plym to the east and Tamar to the west, where they join Plymouth Sound...
- Acid Test: The Global Challenge of Ocean Acidification, by Natural Resources Defense Council
The Natural Resources Defense Council is a New York City-based, non-profit, non-partisan international environmental advocacy group, with offices in Washington DC, San Francisco, Los Angeles, Chicago, and Beijing...
- A Sea Change: Imagine a world without fish, an award-winning documentary and related blog about ocean acidification
- Ocean Acidification in a Nutshell, by Greenpeace Aotearoa New Zealand
Greenpeace Aotearoa New Zealand is one of New Zealand's largest environmental organisations, and is a national office of the global environmental organisation Greenpeace.-History:...
Carbonate system calculators
The following packages calculate the state of the carbonate system in seawater (including pH):
- CO2SYS, a stand-alone executable
In computing, an executable file causes a computer "to perform indicated tasks according to encoded instructions," as opposed to a data file that must be parsed by a program to be meaningful. These instructions are traditionally machine code instructions for a physical CPU...
(also available in a version for Microsoft Excel/VBA)
- seacarb, a R package
R is a programming language and software environment for statistical computing and graphics. The R language is widely used among statisticians for developing statistical software, and R is widely used for statistical software development and data analysis....
for WindowsMicrosoft Windows is a series of operating systems produced by Microsoft.Microsoft introduced an operating environment named Windows on November 20, 1985 as an add-on to MS-DOS in response to the growing interest in graphical user interfaces . Microsoft Windows came to dominate the world's personal...
, Mac OS XMac OS X is a series of Unix-based operating systems and graphical user interfaces developed, marketed, and sold by Apple Inc. Since 2002, has been included with all new Macintosh computer systems...
and LinuxLinux is a Unix-like computer operating system assembled under the model of free and open source software development and distribution. The defining component of any Linux system is the Linux kernel, an operating system kernel first released October 5, 1991 by Linus Torvalds...
(also available here)
- CSYS, a Matlab script
MATLAB is a numerical computing environment and fourth-generation programming language. Developed by MathWorks, MATLAB allows matrix manipulations, plotting of functions and data, implementation of algorithms, creation of user interfaces, and interfacing with programs written in other languages,...