Ocean Acidification: Mechanisms, Impacts on Marine Organisms, and Future Predictions

This essay explains the role of the ocean in regulating earth’s climate, mechanisms of ocean acidification, impacts on marine organisms, and future predictions. It discusses the absorption of CO2 by seawater, which causes ocean acidification and its impact on marine organisms. Desklib offers study material with solved assignments, essays, dissertations, and more.

Running head: OCEAN ACIDIFICATION
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Ocean acidification
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Introduction
The oceans, just like human being lungs, interchange gases with the air. Even though the
rainforest typically gets the recognition, ocean offers an enormous amount of oxygen that makes
the existence on the globe possible. The sea engrosses more than 25% of the CO2 released yearly
by the human into the atmosphere of sea, and it also the primary provider of the oxygen in the
globe, playing a similarly crucial part as the forest. Thus, the marine is the principle ‘lung' of the
sphere and is at the midpoint of the global climate structure (Costanza et al., 2014). In a
sequence of known chemical reactions, CO2 reacts with the seawater occasioning in a drop in
pH. At the start of the industrial revolution, the normal pH of the seawater was approximately 8,
but then again, currently the average is nearer to 8.1. It may not appear like a lot, but how the pH
scale, like the Richter scale, is logarithmic and this represent around 30% increases in acidity
(Ishii & Kimoto, 2009). Covering71% of the realm, the world ocean is a sophisticated ecology
that offers important amenities for the maintenances of existence on earth (Ishii & Kimoto,
2009). Though, the ocean remains to limit global warming, for many eras the force of human
beings specifically CO2 emission, pollution and over-utilisation have degraded marine
ecosystems. For several decades, climate change negotiation did not consider the ocean.
Seawaters are warming up, thereby influencing the dynamics and properties of the oceans,
interaction with the atmosphere and the aquatic habitats and ecosystems (Durack, Gleckler,
Landerer & Taylor, 2014). It is not adequately recognised that daily, the ocean absorbs a quarter
of CO2 formed by humanity. It is trailed by a chemical change of the ocean which results in the
ocean acidification. The acidity of the marine has augmented by 30% over two and a half eras,
and this occurrence continues to increases thus intimidating the sea species (Durack, Wijffels &
Matear, 2012). Anthropogenic carbon dioxide discharges into the air, and successive uptake by

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the water are varying aquatic chemistry. Research suggests that ocean acidification lingers,
reflecting growing CO2 emission. Therefore, it is possible that though organisms will be tolerant,
it will influence much maritime process, organism, including configuration of food webs and
communities. Therefore, this essay will explain in great detail the role ocean play in regulation of
earth’s climate. Similarly, it will discuss the mechanism, and ecological consequences of ocean
acidification, and prediction for the upcoming functioning of the future ocean.
Role of the ocean in regulating earth’s climate
The seawater and atmosphere are intimately linked and exchange energy in the form of
humidity and heat. The ocean absorbs heat more readily than land or ice surfaces, and stores
more heat efficiently. It returns the heat much slower than the land surfaces and contributes to
the more temperature climate of coastal parts (Balmaseda, Trenberth & Källén, 2013). Therefore,
the ocean is a regulator of climate. Variation in energy balance between ocean and atmosphere
play a crucial part in climate variation. Atmospheric circulation influence ocean circulation and
the surface currents are dependent on the winds. Winds mix the surface waters down to the
thermocline, below which the fundamental forces of distribution are connected to salinity and
temperature, impacting the water density (Drijfhout et al., 2014). The ocean contributes to a
significant amount of energy released at the beginning of the cyclones and storms, affecting both
human and continents population. Upsurging cold water coming from the depths near the coasts
are rich in nutrients, profoundly changing the coastal climates. Therefore, taking into account
their fluctuation is essential for the comprehending the climate web (Durack & Wijffels, 2010).
The first three meters of the ocean store much energy as the whole atmosphere and the ocean has
a dynamic capability and substantial thermal inertia. The deep oceans play a significant role in
these capacities for storing and releasing heat. This extreme heat reservoir offers the sea an

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extraordinary duty in moderating the climate changes which control the wind and rain formation
(Balmaseda et al., 2013). The ocean stores and traps CO2, hence averting an extreme greenhouse
impact in the atmosphere. However, as a result, the ocean tends to become acidic due to the
production of carbonic acid. Oceanic phytoplankton also takes part in storing the CO2 in the
surface layer just like all the bio-calcifiers (Durack et al., 2012). Ocean circulation redistributes
sanity and heat which are a crucial aspect in controlling the climate machine. Currents along the
westerns and eastern borders of the continents are critical and the fluctuation in the past led to
the glacial period’s alteration (Jackson, Straneo & Sutherland, 2014).
The ocean plays an essential part in the climate; however biodiversity loss and pollution
affect the sea and cause conditions for the climate variation. The amount of carbon dioxide in
the environment and the ocean is upsurging. The average temperature of air in the lower layer of
an atmosphere; near the sea and the land's surface is rising (Drijfhout et al., 2014). And so,
average sea level is growing faster than ever since the finale of the latest ice age. Rapid
variations in the chemical composition of seawater upset ocean ecosystems that are already
stressed by pollution and overfishing.
Climate change has a direct role in the biological diversity loss. Biodiversity loss
severely affects climate change. Phytoplanktonic chains in the sea are profoundly influenced by
climate alteration and their change effects in return the capacity of the ocean to dissolve CO2
(Smith, Arkin, Ren & Shen, 2012). Similarly, let remember that the impact of rapid climate
change is added to other several concerns: pollution and destruction of the coasts, increasing
systematic exploitation of living resources, and the uncontrolled spread of species (Rignot,
Mouginot, Morlighem, Seroussi & Scheuchl, 2014).

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Mechanisms of ocean acidification
Human actions release CO2 into the atmosphere, which causes atmospheric warming and
weather alteration (Durack, Gleckler, Landerer & Taylor, 2014). Approximately a third to a half
of the CO2 discharged by human events is engrossed into the waters, while this assists in
minimising the degree of the atmospheric warming and climate variation; it also has a chemical
influence on the ocean (Durack et al., 2014). Each day, the sea takes about a quarter of the CO2,
formed by human doings, causing a chemical change of water that result in ocean acidification.
The dissolution of CO2 causes a surge in acidity and reduction in the carbonate ions (CO32-)
which are the constructing blocks needed by aquatic animals and plants to create their shells,
skeletons and the other calcareous assemblies. It is worth noting that marine acidity has enlarged
by 30% in 250 years and could triple by 2100. It intimidates species like mussels and oysters,
and will also effect on oceanic food chains.
Nevertheless, our thoughts on the impacts of ocean acidification on aquatic life are still
only pure. Most people have previously overheard about the climate change and global warming,
initiated by the greenhouse impact. It is also well known that human events are the main
perpetrator; the CO2 generated by the industry and cars. However, ocean acidification remains
poorly comprehended (Held & Soden, 2006).
All the CO2 produced each day does not stay in the air. Oceans absorb one fourth. Without the
presence of the sea, the concentration of CO2 would be higher, causing adverse global warming
(Costanza et al., 2014). For a long time, scientist thought that absorption would not cause
significant consequences for the oceans and the organisms. However, later they realised that
dissolution of CO2 in oceans has been varying its chemistry. It means creating pH fall which is
the measure of the liquid acidity and carbon ions concentration, a significant factor in the

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building block for the formation of skeletons, shells and other calcerous structure in maritime
animals and plants (Purkey & Johnson, 2010).
The world’s waters presently take on average approximately one metric tonne of carbon
dioxide generated by every individual annually. “It is anticipated that the superficial of the
ocean has taken up to 500,000 million tonnes of CO2, about half of all that produced by human
action since 1800” (Drijfhout et al., 2014). By absorbing all this extra CO2, the waters have
buffered the impacts of the atmospheric weather variation. In the sea, CO2 reacts to create weak
carbonic acid and result in more considerable marine acidity. As the CO2 levels increases in the
oceans, the pH also declines. Surface ocean pH has already fast dropped by near 0.1 pH units
since the pre-industrial era. It illustrates a 30% reduction in hydrogen ions (Drijfhout et al.,
2014).
Impact on the marine organism
The CO2 absorption by seawater does not only upsurge the number of protons, but it also
drops the sum of individual particles; the carbonates is utilised by a various marine organism to
create their shells and skeletons. Several of these calcifying animals and plants will, therefore,
encounter hitches when constructing these, and their shells and skeleton might even thaw. When
water acidifies to a particular threshold, it turns out to be corrosive to limestone, a substance used
to create frame and shells. Scientist has done laboratory researches on the procedure of
constructing these calcareous assemblies, in creatures open to states of oceans acidification
anticipated to happen in the upcoming. Adverse impact has been witnessed in some species, for
example in calcifying and pteropods algae. Other organisms might gain from ocean acidification
as more CO2 means increase photosynthesis.

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Ocean acidification may have a direct effect on the organism that is consumed by human
and that form shells such as oysters and clams. Negatives effects on zooplankton could have
indirect consequences for humans similar to those observed in pteropods (Gilly, Beman, Litvin
& Robison, 2013). Many animals rely on the corals or plankton, for example, as their sources of
habitat and food. Oceans acidification could have a significant consequence on biodiversity in
particular biomes. For instance, in the Arctic and North Pacific waters, the tiny pteropod is eaten
by salmon (Allan, Soden, John, Ingram & Good, 2010). A salmon is a valuable food source, and
salmon fisheries employ numerous individuals.
Seawater chemistry will continue to be altered for centuries to come even if we stop all
the CO2 emission (Schmidtko, Heywood, Thompson & Aoki, 2014). However, it is possible to
reduce the ocean acidification. Less and more precise geo-engineering technique has been
suggested to edge ocean acidification. For example, releasing basic compound into the ocean to
prevent acidification and raise pH (Rhein et al., 2013). However, the only risk-free and practical
answer is to counter the cause of the concerns, address the escalating increase in CO2 releases,
mainly through political discussions on the replacement of fossils with renewable sources of
power, carried out both in international and national levels (Rhein et al., 2013).
Predictions for the functioning of the future ocean
The carbon presented mainly in the kind of bicarbonate ions is not steadily dispersed into
the sea, as dissolved carbon proportions are more significant at depth than at the surface. The
spatial dispersal of carbon with depth regulate atmospheric CO2 levels, as only the inorganic
carbon from the ocean surface is in contact with the air and backs to the interchange of CO2
between the ocean and atmosphere. Both physicochemical and biological procedures can
explain this vertical gradient of carbon (Drijfhout et al., 2014).

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Biological process: The phytoplankton existing in the s unit level of the sea use light
energy to achieve photosynthesis. The creation of these carbon-centred constituents reinforced
by solar power is called primary production. It denoted the base of the trophic chains from which
other non-photosynthetic creatures can nourish (Masson-Delmotte et al., 2013). Thus, the
photosynthetic process is an effective mechanism for removing CO2 from the environment and
transporting to the animals.
Physico-chemical process backs to growing carbon circulation with depth. The chilling of
surface water at high latitudes favour capability to dissolve atmospheric CO2, and thus,
increasing their density. The massive surface waters plunge down into deep depths, thus
exporting the CO2 and averting it from more contact with the atmosphere. This course
contributing to the vertical gradient of ocean carbon is referred to as the physical pump. The
excess CO2 leads to a net carbon flux to the ocean due to the imbalance brought between oceanic
CO2 concentration and atmosphere (Masson-Delmotte et al., 2013).
Up to date, and ever since the beginning of the industrial age, the seawater has
unceasingly absorbed a comparatively constant portion of the quantity of CO2 produced by
human actions. But, many pieces of research grounded on the theoretical contemplation, in situ
observation, well-ordered laboratory experiment or sustained by models, propose that multiple
activities may reduce or slow-down the carbon sink (Levitus et al., 2009).
The first sequences of procedures are connected to the chemistry of carbonates and can
ultimately lead to a saturation of anthropogenic CO2 sink (Palmer, Haines, Tett & Ansell, 2007).
The dissolution of anthropogenic CO2 drops the carbonate ion content and thus the buffer
influence of the ocean, which in turn escalates the part of CO2 in contrast to the other forms of
dissolved inorganic carbon classes. Therefore, it may lessen the natural carbon sink efficacy.

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The process occurs in parallel with acidification which could potentially have a severe impact on
the lifecycle of the sea. The second process is connected to the response between different
carbon absorption phenomena and anthropogenic climate change. In the event of the carbon sink
weakening, the variations could lead to a positive reaction that could, in turn, hasten the
phenomenon (Syed, Famiglietti, Chambers, Willis & Hilburn, 2010.
The prospect of the biological pump is hard to project. Even a qualitative approximation
of the impact of change on the maritime remains highly speculative (Domingues et al., 2008).
As the CO2 supply is usually regulating for photosynthesis, the rises in anthropogenic CO2 tend
to arouse plant development. It does not seem to be the situation in marine structures because
dissolved inorganic carbon dioxide is not restraining for carbon fixation photosynthesis. But
photosynthesis is intensely influenced by the temperature, light, mineral nutrients and the
density-reliant stability of the surface water layer. Environmental change and organism
displacement by ocean current causes variability in phytoplankton yield, natural selection and
competitiveness which is also expected to result in variation in carbon sequestration. Therefore,
it is essential to approximate how the manufacture of an organic substance by phytoplankton is
going to be influenced by the change in the ecological condition of the surface seawater. Despite
multiple levels of uncertainty, different prediction created by numerical simulations that join the
climate system and the carbon sequence all point to a reducing water carbon sink owing to global
warming. By 2100, the response between the climate and the carbon cycle could even be
accountable for an additional rise in atmospheric CO2 of many tens of ppm (Cazenave et al.,
2014).
What we expect in future

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The scope of future ocean acidification will be strictly associated with an inevitable rise
in atmospheric CO2. If the greenhouse emission continues as they are doing currently, seawater
could upsurge its acidity by 0.4 by the finale of the century (Cazenave et al., 2014). The ocean
acidification lessens the number of carbonates, a central constructing block in water. It makes it
hard for the aquatic organism, such as plankton and coral to create their skeleton and shells, and
surviving shells may begin to thaw. The current pH of the seawater is exceptionally flexible, and
the creature can cope with its fluctuation of various pH intensities during its existence (Jackson,
Straneo & Sutherland, 2014). The hitches with ocean acidification are the continual nature of the
variation as the peril comes from the lifetime exposure to lesser pH levels. The extreme step of
acidification will affect the scope to which calcifying creatures will be capable of adjusting.
The impact of ocean acidification is not even on all species. Some seagrass and algae
may gain from high concentration in the marine, as they surge their growth and photosynthetic
proportions (Syed et al., 2010). But, a more acidic situation will hurt other aquatic species such
as coral and molluscs. The shells as a skeleton of these animals may become active or less
compact. In the side of the coral reefs, this may make them more susceptible to storm
destruction and the slug the recovery stage. Aquatic organisms could experience a change in
development, plenty and existence in reaction to ocean acidification. Most magnificent species
appear to be more exposed in their initial lifespan phases. For example, juvenile fish have
distress finding an appropriate territory to live.
In spite of various responses between and within marine teams, negative and positive, the
study proposes that ocean acidification will be a driver for significant variations in ocean
ecologies in this era. These fluctuations may become worse by the mutual influence of other
developing climate-connected dangers such as reduction of ocean oxygen intensities, a situation

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recognised as ocean deoxygenating; that is distressing aquatic in some religions (Keeling,
Körtzinger & Gruber, 2009).
The decrease in oxygen content known as deoxygenating of ocean waters globally has
deteriorated in recent times (Costanza et al., 2014). The leading causes are climate alteration and
measurable higher nutrient concentration known as eutrophication due to increased human
actions upsetting the coastal parts. Ocean deoxygenation, warming and ocean acidification are
all compelled by augmented atmospheric carbon dioxide; they comprise many stressors for
maritime systems, the socio-economic significances of which are merely starting to be valued
(Keeling, Körtzinger & Gruber, 2009).
Conclusion
Variations in marine networks will have concerns for human cultures which rely on the
good and the amenities this ecosystem offer. The implication for the community could comprise
significant income deteriorations, loss of employment and occupations. Ocean acidification has
a perspective to affect the food safety. Ecologically and commercially critical marine classes will
be affected, though they may react by various means. Aquatic ecosystems such as coral reefs
guard the seashores against the destructive activities of the hurricane and tornadoes, protecting
the only livable land for the numerous island states. Additionally, the marine capacity to absorb
carbon dioxide falls as ocean acidification upsurges. Thus, more acidic seawater is less operative
in controlling weather change.
While decreasing global greenhouse gas discharges is the decisive answer to marine
acidification, undertaking some puzzling choices and the procedure can assist people to arrange
for the severe effect of ocean acidification (Gilly et al., 2013). At the local level, the ensuing
tactics and controlling’s choices can contribute to the reduction of the acute impact of other

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native stressors and aid marine ecosystem to survive better with varying ecological settings.
Improvement in water quality and development of viable fisheries management practices can
assist lessen the effect of the ocean acidification. Implementation of novel technologies,
justifiable managing of habitats and creation and upkeep of secure marine zones can also help in
the control of these effects.

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