Download Ocean Acidification

Before Ocean Acidification
After Ocean Acidification
Group 4 Project
The Impacts of Ocean Acidification
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Group H
Mentor: Mr. Neil Turner
Members: Karey Shi, Isabelle de Bruin, Oscar Hahn, Darpan Mangwani and Paul D. Park
Ocean Acidification
The Purpose of the Project
The purpose of this project is to investigate ocean acidification, a growing environmental
concern. By exploring the causes and impacts of ocean acidification, we are able to understand
the issue and examine the different aspects of it. It is evident that the level of acidification varies
across oceans, thus through research, we aim to determine which ocean has the highest level
of acidification. Furthermore, we aim to explore the consequences of this issue, following with
ways in which we can reduce ocean acidification. This project incorporates environmental
sustainability methods to tackle this environmental concern, which will further enable us to
create alternative options to reduce our impact on the environment and enforce positive change.
Introduction
Ocean acidification occurs when the ocean’s acidity level rises, causing the pH of the ocean to
decrease. The primary cause of this environmental issue is the level of carbon dioxide in the
atmosphere; oceans absorb this greenhouse gas. Carbon dioxide reacts with seawater to form
carbonic acid. Carbonic acid decreases the pH of the ocean water, further decreasing the
alkalinity of the ocean. However, it is vital for the ocean to maintain both an alkaline
environment and a right chemical balance for marine wildlife.
The level of carbon dioxide in the atmosphere has increased significantly in the last few
decades. This is a growing concern that has already impacted the natural environment severely.
The causes of the rise in carbon dioxide levels include human activities, such as burning fossil
fuels. If the level of carbon dioxide continues to rise, the acidification level will also rise. This
issue affects marine ecosystems and organisms intensely.
The rate of ocean acidification is very fast, and it is continuing to accelerate; it is increasing due
to the growing level of carbon dioxide in the atmosphere. Already, 30% of human-generated
carbon dioxide gas emissions have been taken up by the earth’s oceans. It is a serious
environmental problem, as it is changing the natural balance of carbon dioxide in both the
atmosphere and the various oceans.
The World’s Main Oceans
The Pacific Ocean
The Pacific Ocean is the world’s largest ocean, with it’s borders reaching from Asia and
Australia all the way to the Americas. The 162.25 million square kilometers of the Pacific make
up around 46% of the world’s water surface. From the Pacific, many industries, such as oyster,
crab and fish industries, make a living from sea creatures and provide food for the general
population.
However, there is a very real threat present to these industries and to everyone who looks to the
Pacific for sustenance - ocean acidification.
For people who look to the Pacific for help sustaining themselves, making a living has become
very hard over the past few years and is expected to become much harder.
“The reason? The rising CO2 emission from our cars and power plants were changing
the chemistry of the sea. This phenomenon know as ocean acidification was always
expected to hit shell creatures hard, but that wasn’t supposed to happen until late in the
century.” - The Seattle Times, Sea Change.
A recent study done by the Pacific Marine Environmental Laboratory (PMEL) showed that sea
creatures, such as the red king crab, to increased CO2 levels, they found that the rate at which
the animals died could affect their entire population. This study, along with many others, proves
as evidence to the horrible dangers of ocean acidification.
Most people who have heard of ocean acidification agree it is a huge threat to both sea
creatures and the humans who live off them, and that it will come upon us late in the century.
The sad and scary truth is, the conditions of ocean acidification have presented themselves
prematurely. A recent study done in Hawaii showed that pH levels in the water have dropped
significantly since 1990 to the current year, 2014, and also that levels of CO2 dissolved in the
same
waters are
also
much
greater
in
2014
than in
1990.
This data only shows data from the last 24 years, however, scientists have found that, since the
start of the Industrial Revolution, pH levels in the ocean have dropped by 0.1, which is a 30%
logarithmic increase in acidity!
Figures from the IGBP website on the figures of CO2 levels are follows:
“Ocean acidification by numbers:
● 40%: The increase in atmospheric carbon dioxide (CO2) levels since the start of the
industrial revolution.
● 26%: The increase in ocean acidity from preindustrial levels to today.
● 24 million: The number of tonnes of CO2 the ocean absorbs every day.
● 10 times: The current rate of acidification is over 10 times faster than any time in the last
55 million years.”
The ocean serves as a huge sink to absorb the carbon dioxide that we humans produce from
our power plants and other sources such as cars, taking up to one fourth of all that CO2;
however, it has been shown that due to rising temperatures in the ocean and higher pH levels,
the sea is no longer as efficient in absorbing CO2. Also, ocean acidification results in shell
creatures having their shells deteriorate due to the imbalance of carbonate ions in the water.
Many of these organism are large parts of food chains, whether as microorganisms or as food
for humans.
The Atlantic Ocean
The Atlantic ocean, the second largest ocean in the world behind the pacific ocean, with a total
area of about 106,400,000 square kilometres. It is bounded on the west of North and South
America.
Ocean Acidification is an ongoing problem in all of the oceans and is caused by the intake of
carbon dioxide (CO2) in the water. Even though the gradual increase of acidity in the ocean is
not the same as it is in fizzy drinks, it still causes problems for the marine environment that have
to adapt to the new acidity in the water.
There are certain figures in which one can measure the amount of acidity, this can be done with
a pH indicator, that follows the pH scale where it goes from 1 to 14, where 1-6 is acidic (1 being
the most acidic), 7 is neutral, and 8-14 is basic (14 being the most basic). And another way of
identifying the acidity levels in the ocean is by measuring the amount of carbon dioxide in the
water, since Carbon dioxide is the main cause of ocean acidification. Carbon Dioxide levels are
measured in micro-atmospheres as partial pressure, which is a common way of measuring the
amount of gas.
The graphs below show the level of Carbon Dioxide and the pH level of the water in the Atlantic
Ocean. The up and down patterns show the influence of seasonal variations. The graphs show
that, as years go by, the amount of CO2 in the ocean increases, as well as the pH level
decreases, which means it becomes more acidic. The usual levels for pH values in an ocean is
about 8.1 and 8.2, and in the last 70 years it has gone down by 0.2-0.3, which means ocean
aci
difi
cati
on
has
incr
eas
ed.
Unless humans try and stop the emission of CO2 in the atmosphere, sea creatures will have to
learn to adapt to their new habitat that is contaminated and brutally damaged. In addition, it also
harms oxygen levels, since It decreases oxygen levels by killing algae. Also it decreases
immune responses on some organisms as well as causes coral bleaching.
The Indian Ocean
The Indian Ocean, the world’s third largest oceanic division, covers over 20% of the water on
the Earth. It bounds Asia on the north, Africa on the west, Australia on the east, and also the
Southern Ocean on the south. . At the same time, due to its borders with the middle east, it is
also one of the oceans worst affected by global warming.
Over the past 300 million years, ocean pH has been slightly basic, averaging about 8.2. Today,
it is around 8.1, a drop of 0.1 pH units, representing a 25% increase in acidity over the past two
centuries.
The acidity of the Indian Ocean is believed to be contributed by the long-range transport of
gaseous pollutants such as SO2 and NO2 from the Indian subcontinent, by the north-east trade
wind. This have caused impact such as ocean calcification, on not only the Indian Ocean but
every other ocean in the world. As the ocean pH falls, whereas it gets more acidic, the
concentration of carbonate ions required for saturation to occur increases, and when carbonate
becomes undersaturated, structures made of calcium carbonate are vulnerable to dissolution.
The rainwater over the Indian Ocean is also observed as acidic (pH<5.6) across the InterTropical Convergence Zone.
The acidic components in the Indian Ocean are mainly sulphate, which may have been
produced during SO2 oxidation. Non-sea salt SO4 and non-sea salt Ca were also very high,
especially
near
the
continent.
The
Ocean
Arctic
The Arctic Ocean is centered in the Arctic North Polar Region, surrounded by Eurasia and North
America. It is the smallest and shallowest ocean in the world. Throughout the year, the Arctic
Ocean is covered by sea ice, however, the surface temperature and salinity vary seasonally.
Due to the changing climate, the Arctic waters have become increasingly vulnerable to factors
such as ocean acidification. Already, regions of the Arctic Ocean are showing effects of this
environmental issue.
Although ocean acidification is a global problem, it is apparent that the effect varies per ocean.
Through research, it is found that the Arctic Ocean is among the worlds most sensitive in terms
of its response to climate change; this is explained through the various discoveries made by the
Arctic Monitoring and Assessment Programme.
It is evident that the Arctic Ocean is experiencing widespread effects of ocean acidification.
These effects can be seen in the different seas of the Arctic Ocean. Ocean acidification is
occurring over a wide range of depths in the Nordic Seas. Absorption occurs rapidly in surface
waters, however, it occurs more slowly in deep waters. In Iceland and the Barents Seas, the pH
of seawater is decreasing at a rate of roughly 0.02 per decade, since the late 1960s. Finally, the
surface waters of the Bering Strait and the Canada basin have also shown effects; the notable
chemical changes found in surface waters relate to acidification. Although the magnitudes of
acidification in the Arctic Ocean vary, the entire ocean is facing the consequences of this issue.
The Arctic Ocean consists of cold water; it has a fairly constant temperature of 0°C. Cold
waters, however, have a high capacity to absorb carbon dioxide; it favors the transfer of carbon
dioxide from the atmosphere into the ocean. This further underlines that the rate of absorption in
the Arctic Ocean is much higher than in any other ocean. As carbon dioxide is absorbed at a
much faster pace, the dissolution of calcium carbonate is promoted. Finally, the absorption
takes place on surface waters; this lowers the pH, creating an acidic environment.
Furthermore, due to the changing climate, sea ice has been reduced; this creates many open
water surfaces. As more seawater is exposed, more carbon dioxide is able to be absorbed into
the ocean. This may further alter the production and decomposition of organic carbon. Every
year, the amount of open water is growing due to climate change, which is decreasing the Arctic
summer sea ice. If the sea ice continues to melt, the exposure of seawater will expand, allowing
a greater transfer of the greenhouse gas into the ocean, resulting to an increase in the level of
acidification.
The addition of fresh water into the ocean contributes to ocean acidification. Large quantities of
fresh water are supplied from rivers and melting ice, and enter the Arctic Ocean. Fresh water
contains large amounts of organic matter, which will increase the carbon dioxide content in
oceanic water. Freshwater further dilutes the salinity, alkalinity and carbon content of the ocean,
creating an unbalanced equilibrium of sea water with the atmosphere. This unbalanced
equilibrium promotes the absorption of carbon dioxide; carbon dioxide is absorbed to restore
the equilibrium. The Arctic waters are less effective at chemically neutralizing these acidifying
effects.
The Consequences of Ocean Acidification
The carbonate systems of all the worlds oceans are changing rapidly, due to ocean acidification.
Previous, mass extinction events have been linked to ocean acidification and the current rate of
change in seawater chemistry has never been seen before. Studies suggest that the vast
changes will have great impact on marine life/taxa. Research shows that increased ocean
acidification can potentially have great impact on species distribution and it could very well
propagate through multiple trophic levels of marine food webs. Research into the long-term
consequences of ocean acidification, and long-term impacts on ecosystems is still only in its
early stages.
The debate about CO2 emissions should take into account the risk of irreversible ecosystem
changes, all due to ocean acidification, as well as make it clear that human dependency on
fossil fuels must come to halt before it is too late. Grand investments in clean energy, as well as
actual will from politicians is a necessity to stop climate change and ocean acidification.
Marine food webs in the arctic depend greatly on specific key species such as: sea butterflies,
sea stars, urchins etc, that are very sensitive to ocean acidification and upsetting any of them
could mean significant change to food webs and the ecosystems, for the worse. As there is very
little data on the arctic marine life and how they react to ocean acidification, long term-studies
on the matter are urgently needed, as almost all studies have been conducted in oceans other
than the arctic.
It has been proven that organism growth, and shell formation on some organisms have been
affected by ocean acidification. Some animals grow slower when exposed, however some
seagrass thrive. Birds and mammals out of water do not get affected directly by the acidification,
but if their food source relocates, declines, or other, then it starts to impact them.
In general, its mostly organisms in their earliest stages of life that are the most exposed.
Juvenile and adult fish are believed to be able to sustain the acidification for another century or
so, but fish eggs and early larval stages are the most affected.
Ocean acidification also has economic impacts and consequences. Ocean acidification can
easily affect quality, quantity, and predictability of fish stocks. Fish stocks might be able to
withstand the acidification more if for example overfishing is minimized. Many coastal
communities in the north are likely to be affected by ocean acidification. They fish and harvest
many organisms that get affected, but they may be able to shift over to less affected species,
this might affect cultural practices/traditions however. Like birds and mammals, residents of
these coastal communities are also likely to be indirectly affected by ocean acidification.
Our Approach to Minimize the Impact of Ocean Acidification
Ocean acidification is a phenomenon occurring globally, and one that will have huge negative
repercussions throughout the world if it is not dealt with. So what are some ways we can
minimize the impact of ocean acidification?
1. Reducing Carbon Dioxide Emissions
First and foremost, we must reduce our carbon footprint. The ocean has always been the
world’s great carbon dioxide sink; however the rising CO₂ levels have caused the water to
become more and more acidic, so lowering the emission of this overly-abundant gas seems to
be the most logical solution.
Ways that we can reduce our carbon footprint are:
●
●
●
●
Reducing the amount of distance traveled by car, or car pool if you must. Cars produce
the highest amounts of CO₂ due to their proliferous use today. If possible, try avoiding
cars altogether, using bicycles to travel.
Replace incandescent light bulbs with brighter, more eco-friendly LED bulbs. Save the
world, and the ocean.
Eat less red meat! This is surprisingly effective in reducing our footprint.
Turn off the lights when you’re not in the room; it’s simple but the amount of electricity
wasted due to this apparent triviality.
More large-scale methods would include:
● Solar panels! Use plenty of them to power your house rather than relying on carbonburning plants.
● Support other forms of clean energy.
2. Climate Engineering
One method that could possibly help with ocean acidification is climate engineering, which also
works by reducing carbon in the air, but not as simply as turning off the lights. More specifically,
however, Solar Radiation Management, which involves reflecting the heat from the sun back
into space, rather than allowing them to stay trapped inside the greenhouse gas layer of Earth.
Companies such as Platinum Roofing can help change roofs of buildings so that they reflect
solar heat and rays with ease.
3. Iron Fertilisation
Iron fertilisation involves adding iron to the ocean, which results in prodigious amounts of
plankton in that area. In theory, these plankton would use the carbon dioxide in the water to
photosynthesise and convert it into oxygen. At the same time, the reaction would cool down the
Earth’s temperature, increasing once more the ocean’s ability to retain dissolved carbon dioxide.
Nonetheless, iron fertilisation is highly unreliable due to the fact that a) it’s efficiency is unknown
and b) the consequences it could result in are unpredictable.
4. Carbon Negative Fuels
Carbonic acid is extracted from seawater as CO2 to make synthetic fuels. If the resulting flue
exhaust gas is subject to carbon capture, then the process will become carbon negative over
time, where permanent extraction of inorganic carbon from seawater and the atmosphere with
which seawater is in equilibrium. A big disadvantage of this process would be considered the
affordability, based on the energy requirements for the technology, this process was estimated
to cost about $50 per tonne of CO2.
Conclusion
It is evident that the level of acidification varies across oceans, however, it remains a global
issue. Through comparing and investigating the levels of acidification in the four main oceans,
we have come to the conclusion that the Arctic Ocean has the highest level of acidification; its
response to this issue is also the most severe. The consequences of acidification impact the
marine environment and ecosystems severely, which will further affect communities and
lifestyles that base their income on fishing and other marine animals, as a result. Aware of the
problem, we have identified four key ways to reduce ocean acidification, which include reducing
our carbon emissions, climate engineering, iron fertilisation and carbon negative fuels. Through
researching and learning about ocean acidification, we have understood the severity of this
growing environmental concern, and we will implement these new strategies to reduce
acidification in oceans, in our everyday lives.
Works Cited
On the Pacific Ocean:
●
●
●
●
●
"Ocean Acidification by Numbers." IGBP. N.p., n.d. Web. 22 Nov. 2014.
<http://www.igbp.net/news/news/news/oceanacidificationwebsitelaunched.5.43f6bb4c14
492917277163.html>.
"What Is Ocean Acidification?" PMEL. N.p., n.d. Web. 20 Nov. 2014.
<http://www.pmel.noaa.gov/co2/story/What+is+Ocean+Acidification%3F>.
"Societies and Economies." Ocean Acidification. N.p., n.d. Web. 22 Nov. 2014.
<http://ocean-acidification.net/2014/03/20/ocean-acidification-societies-andeconomies/>.
"Pacific Ocean Takes Perilous Turn." The Seattle Times. N.p., n.d. Web. 22 Nov. 2014.
<http://apps.seattletimes.com/reports/sea-change/2013/sep/11/pacific-ocean-perilousturn-overview/?prmid=4749>.
"Ocean Acidity." EPA. Environmental Protection Agency, n.d. Web. 21 Nov. 2014.
<http://www.epa.gov/climatechange/science/indicators/oceans/acidity.html>.
On the Atlantic Ocean:
● "Ocean Acidity." EPA. Environmental Protection Agency, n.d. Web. 17 Nov. 2014
● "Ocean Acidification." English Name of the Content Author / Nom En Anglais De L'auteur
Du Contenu. N.p., n.d. Web. 17 Nov. 2014.
● "Ocean Acidification." Smithsonian Ocean Portal. N.p., n.d. Web. 18 Nov. 2014.
● "Ocean Acidification." N.p., n.d. Web. 19 Nov. 2014.
● "Climate Science Glossary." Skeptical Science. N.p., n.d. Web. 19 Nov. 2014.
On the Indian Ocean:
● Kulshrestha, U. C., Monica Jain, T. K. Mandal, Prabhat K. Gupta, A. K. Sarkar, and D. C.
Parasar. "Measurements of Acid Rain over Indian Ocean and Surface Measurements of
Atmospheric Aerosols at New Delhi during INDOEX Pre-campaigns." (1999): n. pag. 10
Apr. 1999. Web. 17 Nov. 2014.
● "Climate Science Glossary." Skeptical Science. N.p., n.d. Web. 22 Nov. 2014.
●
Wikipedia. Wikimedia Foundation, n.d. Web. 22 Nov. 2014.
●
"Ocean Acidification -- National Geographic." National Geographic. N.p., n.d. Web. 20
Nov. 2014.
Newton, J. A., R. A. Feely, E. B. Jewett, and D. Gledhill. "Toward a Global Ocean
Acidification Observing Network." Toward a Global Ocean Acidification Observing
Network (n.d.): n. pag. NOAA, IOCCP, GOOS, IOOS, and UW, 28 June 2012. Web. 17
Nov. 2014.
"Indian Ocean." Wikipedia. Wikimedia Foundation, 19 Nov. 2014. Web. 22 Nov. 2014.
●
●
On the Arctic Ocean:
● Arctic Monitoring and Assessment Programme (AMAP). Arctic Ocean Acidification
Assessment: Summary for Policymakers. Oslo, Norway: AMAP, 12 Jan. 2013. PDF.
● Arctic Monitoring and Assessment Programme (AMAP). "Arctic Ocean Acidification
(2013) - Full (12 Minute) Version." Vimeo. Alpha Film, 2013. Web.
<http://vimeo.com/65512340>.
● USGS. "Ocean Acidification." USGS - Science for a Changing World. N.p., 15 Apr. 2014.
Web. 12 Nov. 2014. <http://coastal.er.usgs.gov/ocean-acidification/polar.html>.
● Cheek, Joseph. "Explaining Ocean Acidification and Consequences for Arctic Marine
Ecosystems." SciencePoles. 31 Mar. 2014. Web. 12 Nov. 2014.
●
●
●
<http://www.sciencepoles.org/interview/explaining-ocean-acidification-andconsequences-for-arctic-marine-ecosystem>.
EPOCA. "What Is Ocean Acidification?" What Is Ocean Acidification? Observatoire
Océanologique De Villefranche Sur Mer, n.d. Web. 18 Nov. 2014. <http://www.epocaproject.eu/index.php/what-is-ocean-acidification.html>.
Ostenso, Ned Allen. "Arctic Ocean." Encyclopedia Britannica. N.p., 6 Nov. 2013. Web.
18 Nov. 2014. <http://global.britannica.com/EBchecked/topic/33188/Arctic-Ocean>.
Self Edited. "Arctic Ocean." Wikipedia. Wikimedia Foundation, 4 Nov. 2014. Web. 18
Nov. 2014. <http://en.wikipedia.org/wiki/Arctic_Ocean>.
On the consequences of acidification:
● Guinotte, John M. "Ocean Acidification and Its Potential Effects on Marine Ecosystems."
Guinotte. John Wiley & Sons, Inc., 28 June 2008. Web. 23 Nov. 2014.
● "Ocean Acidification." Ocean Acidification. PMEL Carbon Group, n.d. Web. 21 Nov.
2014.
●
Arctic Monitoring and Assessment Programme (AMAP). Arctic Ocean Acidification
Assessment: Summary for Policymakers. Oslo, Norway: AMAP, 12 Jan. 2013. PDF.
On the reduction of acidification:
● "14 Ways to Reduce Your Carbon Footprint." COTAPorg. N.p., n.d. Web. 21 Nov. 2014.
<http://cotap.org/reduce-carbon-footprint/>.
● "Ocean Acidification -What You Can Do." NRDC. N.p., n.d. Web. 22 Nov. 2014.
<http://www.nrdc.org/oceans/acidification/what-you-can-do.asp>.
● "Ocean Acidification - Possible Responses." Wikipedia. Wikimedia Foundation, n.d.
Web. 22 Nov. 2014.
<http://en.wikipedia.org/wiki/Ocean_acidification#Possible_responses>.
● "Fertilizing the Ocean with Iron." Oceanus Magazine. N.p., n.d. Web. 22 Nov. 2014.
<http://www.whoi.edu/oceanus/feature/fertilizing-the-ocean-with-iron>.
Images
● The UK Ocean Acidification Research Programme Knowledge
● Exchange Office. "Ocean Acidification." UK Ocean Acidification Research Programme.
Web. 18 Nov. 2014. <http://www.oceanacidification.org.uk/>.
● Moyer, Ryan P. "Impacts of Ocean Acidification on Coral Growth: Historical Perspectives
from Core-Based Studies." Sound Waves. Nov. 2009. Web. 18 Nov. 2014.
<http://soundwaves.usgs.gov/2009/11/>.
PLANNING
The following pages consist of our research, planning, drafts and more, for our project.
Group 4 Project
DEADLINE: November 21, 2014
Group H
Mentor: Mr. Neil Turner
Members:
- Karey
- Isabelle
- Oscar
- Darpan
- Paul
Possible Research Topic
Isabelle:
- Sea temperature rise
- Ocean acidification
How do the levels of acidification vary across the oceans?
- Sea level rise
- Marine Ecosystem (includes pollution)
Darpan:
-
Ocean as a system.
Climate and sea level
Life in the oceans
Marine resources
Sea under threat
Marine Hazards
Carbon dioxide emissions in Oceans
Oscar:
●
●
Effects on Marine Ecosystems:
Carbon dioxide problem
Paul:
- Marine Pollution
- Oil Spills
- Overfishing
Karey:
●
●
●
Heat capacity of the ocean
Newton’s law of cooling
analyze pollution content
●
Industrial water and impacts on the ocean
The Purpose of the Project
To investigate the level of acidification in the main oceans, and to determine which ocean has
the highest level of acidification. In addition, we aim to explore the consequences of this issue
and ways in which we can reduce these levels and enforce green sustainability.
Areas of Investigation
●
●
●
●
●
●
Pacific Ocean - Paul
Atlantic Ocean - Darpan
Indian Ocean - Karey
Arctic Ocean - Isabelle
Consequences of ocean acidification - Oscar
Green sustainability/ reducing acidification levels - EVERYONE
Things to include for Oceans:
●
●
Figures for the different components of acidity (carbon dioxide levels etc.), pH levels,
percentages etc.
Reasons/ explanations to why the ocean has the level of acidity it has
Things to include for consequences:
●
●
●
The effect on marine ecosystems if levels rise
Ideal level
Effect of high acidity levels on the ocean/world as a whole
IMPORTANT DATES
Thursday, November 6: Group Meeting during Period 4 - in front of the Library (research
possible topics)
Saturday, November 8: Individual research topic should be chosen
Monday, November 10: Group Meeting at 12:10 - in front of the Library (discuss research
project)
Friday, November 14: Notes on individual sub-topic
Group Meeting at 12:10 - in front of the Library (Comment on our
research)
Monday, November 17: Paragraphs on individual sub-topic
Tuesday, November 18: Comment and edit work from others
Group Meeting at 12:10 - In front of the Library
(Discuss the presentation of our research)
Wednesday, November 19: Finalize research and display it in a presentable way
Thursday, November 20: Finish personal reflection on Group 4 topic
Group Meeting at 12:10 - in front of the Library (Final meeting to see
if everything is complete)
Research Notes
Isabelle - The Arctic Ocean:
Source: Arctic Monitoring and Assessment Programme (AMAP). Arctic Ocean Acidification
Assessment: Summary for Policymakers. Oslo, Norway: AMAP, 12 Jan. 2013. PDF.
Ocean Acidification: “an increase in the acidity of the ocean over an extended period, which is
caused primarily by the uptake of carbon dioxide from the atmosphere”
● Higher levels of carbon dioxide in the atmosphere = greater amount of carbon dioxide
absorbed in the ocean
○ RESULT = ocean acidification
■ Affects marine ecosystems and organisms - (from plankton to fish)
● Arctic waters are particularly vulnerable to ocean acidification
○ Cold waters have a higher capacity to absorb carbon dioxide
○ The reduction of sea ice (resulting from climate change) contributes to an
increased absorption in CO2 at high latitudes
○ Regions of the Arctic Ocean are already showing effects of acidification
○ Ocean acidification within the Arctic has the potential to affect the livelihoods of
northern communities
■ Communities which rely on recreational and subsistence fishing and
ecotourism
●
Ocean acidification is occurring at a rapid and accelerating pace
○ The Arctic Ocean is on the frontline of this global change
○ Measurements around the globe show that ocean acidity is increasing
■ These measurements are consistent with the observed findings of:
■ - increased CO2 levels in the atmosphere
■ - increased uptake of some CO2 by the oceans
○ The resulting chemical reactions include adding carbon dioxide to seawater =
increasing the ocean’s acidity
○ Acidity is a fundamental chemical property of seawater (like salinity)
■ Ocean acidification is an issue = it has the potential to exert far-reaching
effects on marine plants and animals = affecting human societies
○ Human activities are the primary cause of the ongoing increase of CO2 in the air
and oceans
■ Especially burning fossil fuels
○ Natural processes in the ocean counter this increase by burying some of this
‘extra’ carbon in deep sea sediments = very slow process
○
●
Scientists project that the acidification footprint of human activities will remain in
the upper ocean for many tens of thousands of years
Experts do not yet understand Arctic systems well enough to predict specific
consequences of ocean acidification with a high degree of certainty
○ A growing body of evidence suggests that Arctic ecosystems are facing
increasing risk from a combination of major changes
■ They include
- Climate change
- Harvesting
- Habitat degradation
The field of Ocean Acidification research is new and rapidly evolving.
The Arctic Ocean Acidification assessment report have confirmed the following findings:
1. Arctic marine waters are experiencing widespread and rapid ocean acidification
- Scientists have measured significant rates of acidification at several Arctic Ocean
locations
- In the Nordic Seas = acidification is taking place over a wide range of depths
- Most rapidly in surface waters
- More slowly in deep waters
- Iceland and Barents Seas
- Decreases in seawater pH of about 0.02 per decade have been
observed since
the late 1960s
- The surface waters of the Bering Strait and the Canada Basin of the central
Arctic Ocean
- Notable chemical effects related to acidification have been
encountered in surfaces waters
2. The primary driver of ocean acidification is the uptake of carbon dioxide emitted to the
atmosphere by human activities
● Carbon dioxide is released to the atmosphere when carbon-rich materials are burned
○ Include coal and oil – burned at power stations
● Some of this gas is absorbed by the oceans
○ Slowing its build up in the atmosphere
○ Increasing the pace of human-induced climate warming
○ Increasing seawater acidity
● The average acidity of surface ocean waters worldwide is about 30% higher than at the
start of the Industrial Revolution
○ Result of carbon dioxide emissions
3. The Arctic Ocean is especially vulnerable to ocean acidification
● The Arctic Ocean has large quantities of freshwater supplied from rivers and melting ice
● The Arctic Ocean is less effective at chemically neutralizing carbon dioxide’s acidifying
effects = increasing climate change
● The Arctic Ocean is cold
●
●
○ Cold water favours the transfer of CO2 from the air into the ocean
As a result of these two influences, Arctic waters are among the world’s most sensitive in
terms of their acidification response to increasing levels of CO2
The amount of open water is increasing every year due to the recent and projected
dramatic decreases in Arctic summer sea-ice
○ This allows for a greater transfer of CO2 from the atmosphere into the ocean
4. Acidification is not uniform across the Arctic Ocean
● Other processes can be important in determining the pace and extent of ocean
acidification
○ Include:
■ Rivers, sea-bottom sediments and coastal erosion
● These processes all supply organic material that bacteria can
convert to CO2 = increasing the process of
ocean acidification, especially on the shallow continental shelves
■ Sea-ice cover, freshwater inputs and plant growth and decay
● All influence local ocean acidification
● The contribution of these processes vary:
○ Place to place
○ Season to season
○ Year to year
■ The result of this variation = a complex, unevenly distributed, everchanging pattern of Arctic acidification states
HOW TO ADDRESS THIS SERIOUS ISSUE
● More than a quarter of global CO2 emissions from fossil fuels come from the Arctic
Council State
○ Immediate cuts in CO2 emissions is essential to slow the acidification of the
Arctic Ocean
○ It is recommended that the Arctic Council:
■ Reduce the emission of CO2
■ Expand their understanding of acidification processes and their effects by
carrying out enhanced research and monitoring effects
■ Implement adaptation strategies to address all aspects of Arctic change
Source: Arctic Monitoring and Assessment Programme (AMAP). "Arctic Ocean Acidification
(2013) - Full (12 Minute) Version." Vimeo. Alpha Film, 2013. Web.
<http://vimeo.com/65512340>.
●
●
●
●
Strong evidence of ongoing climate change in the Arctic
“Once carbon dioxide enters the ocean, the legacy of ocean acidification will last for
thousands of years” – Richard Bellerby
The Arctic is highly vulnerable to climate change
Burning coal, oil and gas (fossil fuels) = changing the composition of the atmosphere
○
●
The natural balance of CO2 in the atmosphere and surface waters has been
overturned
○ Result = massive amounts of CO2 is absorbed in surface waters
Disappearing sea-ice is opening up more ocean = can absorb CO2 faster
Source: USGS. "Ocean Acidification." USGS - Science for a Changing World. N.p., 15 Apr.
2014. Web. 12 Nov. 2014. <http://coastal.er.usgs.gov/ocean-acidification/polar.html>.
●
●
●
The Arctic Ocean has a fairly constant temperature of 0°C
Reasons to why ocean acidification may be occurring faster at the poles than other
climate regions:
Cold water absorbs more CO2 = lowers the pH = promotes calcium carbonate dissolution
○ Added melt-water and increased river input = forces additional uptake of CO2
○ Reduced sea-ice coverage = more seawater is exposed = more CO2 is absorbed
○ Expanded ocean-surface area may alter the production and decomposition of
organic carbon
Source: Cheek, Joseph. "Explaining Ocean Acidification and Consequences for Arctic Marine
Ecosystems." SciencePoles. 31 Mar. 2014. Web. 12 Nov. 2014.
<http://www.sciencepoles.org/interview/explaining-ocean-acidification-and-consequences-forarctic-marine-ecosystem>.
●
●
●
●
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Top layer of the ocean mixes with gasses found in the atmosphere
○ Gases dissolve in the ocean
○ CO2 + H2O -> H2CO3
○ Forms carbonic acid
○ Increases pH
○ Decreases alkalinity of ocean water
Earth’s oceans have taken up more than 30% of human-generated CO2 emissions
○ Decreased pH of ocean water by 30%
Maintaining the right chemical balance in the ocean is important for marine organisms
Maintaining an alkaline environment is essential for good internal cell functioning of
many organisms
Freshwater runoff contributes to ocean acidification
○ Freshwater contains large amounts of organic matter
○ Organic matter leads to an increase in CO2 in the water = remineralization of
organic matter by organisms = organisms produce CO2
Source: EPOCA. "What Is Ocean Acidification?" What Is Ocean Acidification? Observatoire
Océanologique De Villefranche Sur Mer, n.d. Web. 18 Nov. 2014. <http://www.epocaproject.eu/index.php/what-is-ocean-acidification.html>.
●
●
●
Freshwater from melting ice caps dilute the concentrations of all the various components
of the carbonate system in seawater
Freshwater would dilute the salinity, alkalinity, and carbon content to half of what they
were, and the initial pH would increase
The seawater would be out of equilibrium with the atmosphere and so it will absorb CO2
until the seawater reaches equilibrium again
Darpan:
-General Ocean acidification sites
http://www.coral.noaa.gov/research/climate-change/ocean-acidification.html
http://www.pmel.noaa.gov/co2/story/Ocean+Acidification
http://ocean-acidification.net/
http://www.nature.com/nclimate/journal/v2/n1/full/nclimate1324.html
http://ocean.si.edu/ocean-acidification
-Ocean acidification websites on Atlantic ocean
http://www.epa.gov/climatechange/science/indicators/oceans/acidity.html
http://www.dfo-mpo.gc.ca/science/oceanography-oceanographie/impacts/acidification-eng.html
Ocean acidification in the Atlantic ocean
Question is, why the ocean has the level of acidity it has, the answer to that is, that fossil fuel
powered machines have increased by a large amount in the last few years, and it is an
advantage to mankind since it helps the advancement in industry. the downside to this is that
these fossil fuels release CO2 and other greenhouse gases into the atmosphere.
Reports have shown that half of this CO2 that is available in the atmosphere are absorbed into
the ocean.
The amount of CO2 decreasing in the atmosphere is an advantage, however it has been shown
that high amounts of CO2 have changed and altered water chemistry.
The CO2 has also changed life cycles for the marine organisms, especially those animals that
are at the bottom of the food chain.
When CO2 dissolves in the ocean it forms Carbonic Acid, which increases the acidity in the
ocean. These levels of acidity have been proven to inhibit shell growth in marine animals
and it is also suspected that these levels are the cause of some disorders in fish.
Unless humans try and stop the emission of CO2 in the atmosphere, sea creatures will have to
learn to adapt to their new habitat that is contaminated and brutally damaged.
It also decreases oxygen levels since it kills algae.
Decreases immune responses on some organisms as well as causes coral bleaching.
-These graphs suggest correlation between the year and the amount of carbon dioxide (one of
the main components) in the ocean. the CO2 is measured in micro-atmosphere which is a
frequent way to measure the amount of gas. these graphs also show the pH level of the water in
those specific areas of the north atlantic ocean. the results for the pH levels of the water are
quite low, meaning that they are a bit above the neutral level; also some are a bit more basic
than others from the graphs. however, the normal numbers for pH levels are about 8.1/ 8.2.
http://www.epa.gov/climatechange/science/indicators/oceans/acidity.html
In the past 70 years, in some parts of the Atlantic ocean, pH levels have decreased by 0.2 or
0.3, which means it has become more acidic. This is due to the increases in anthropogenic CO2
emissions.
Oscar:
● Effects on Marine Ecosystems:
http://onlinelibrary.wiley.com/doi/10.1196/annals.1439.013/abstract;jsessionid=41697C4065A1B
D69710E82F7E59FB740.f01t01?deniedAccessCustomisedMessage=&userIsAuthenticated=fal
se
● Carbon dioxide problem:
http://www.pmel.noaa.gov/co2/story/Ocean+Acidification
● PDF
http://www.amap.no/documents/doc/amap-arctic-ocean-acidification-assessment-summary-forpolicy-makers/808
Paul:
- Data on North Atlantic and Pacific (CO2 levels):
http://www.epa.gov/climatechange/science/indicators/oceans/acidity.html
-Great video on Ocean Acidity:
http://apps.seattletimes.com/reports/sea-change/2013/sep/11/pacific-ocean-perilous-turnoverview/?prmid=4749
-Dissolved CO2 in Pacific Ocean in 1990 approx. 325 micro-atmospheres, in 2014 approx. 375
micro-atmospheres. pH levels from approx. 8.11 in 1990 to approx. 8.05 in 2014
Source: TreeHugger - Climate Change Reducing Ocean’s Ability to Absorb Carbon Dioxide
http://www.treehugger.com/clean-technology/climate-change-reducing-oceans-ability-to-absorbcarbon-dioxide.html
Warmer temperatures is impacting how the ocean is able to absorb CO2 from the atmosphere.
While the ocean acts as a natural carbon sink, global climate change is slowing its ability to
suck up CO2 in large swaths of the subtropical North Atlantic, University of Wisconsin-Madison
assistant professor Galen McKinley has shown in a new study. The ocean struggling to absorb
CO2, and even slowing its absorption is something researchers realized a few years ago, but
the reasons may be even more clear after this recent study.
University of Wisconsin-Madison reports, "Working with nearly three decades of data, the
researchers were able to cut through the variability [that has caused conflicting results in
previous studies] and identify underlying trends in the surface CO2 throughout the North
Atlantic. During the past three decades, increases in atmospheric carbon dioxide have largely
been matched by corresponding increases in dissolved carbon dioxide in the seawater...But the
researchers found that rising temperatures are slowing the carbon absorption across a large
portion of the subtropical North Atlantic. Warmer water cannot hold as much carbon dioxide, so
the ocean's carbon capacity is decreasing as it warms."
Because the ocean has been absorbing more and more of the CO2 humans release into the
atmosphere -- about a third of the planet's CO2 is taken in by the ocean -- the ocean has been
becoming both more acidic. Primary concerns of researchers have been both how to get the
ocean to absorb ever more CO2 to help reduce what is in the atmosphere, and deal with the
changing chemistry of the ocean which is impacting much of the flora and fauna. However, the
results of this study show that as the ocean warms along with the planet, at least some parts of
it will be less and less able to absorb CO2 from the atmosphere.
"More likely [than seeing the ocean's carbon levels surpass that of the atmosphere] what we're
going to see is that the ocean will keep its equilibration but it doesn't have to take up as much
carbon to do it because it's getting warmer at the same time," she says. "We are already seeing
this in the North Atlantic subtropical gyre, and this is some of the first evidence for climate
damping the ocean's ability to take up carbon from the atmosphere."
McKinley found these results after looking at data from 1981 to 2009 taken from broad
samplings. She stresses that the same level of analysis needs to be extended to other areas
beyond the North Atlantic to discover how other parts of the ocean are responding to carbon
emissions and warming. This kind of information can be critical to the accuracy of carbon and
climate modeling for future scenarios of global warming.
What Can I Do?
One of the main reasons why it is hard to fix this growing crisis is that it is hard to raise
awareness. Or, more accurately, it is easy to raise awareness, but it is hard to raise a
willingness to change. People see their actions as inconsequential, or they think that the only
things they can do to help are too expensive.
Another reason is that all the new data and findings are counting for very little, because the
people reading then already know ocean acidification is a huge problem. And, again, even the
people who do become concerned about the problem by reading or hearing something don’t
necessarily know how to help.
On an individual level, it is important to keep in mind that we can make a change, however
small. Bike to work or school once a week, shut off your lights every day before leaving the
house, invest in alternative energy sources (that is, those that do not rely on carbon emitting
fossil fuels) and spread the word about the perilous situation in which we find our oceans to help
make ocean acidification a common term in everyday life. We are now at an intersection. One
road leads to a bright future filled with the benefits that the ocean brings, and the other to an
uncertain and desolate end to the oceans that make our home. Which way will we chose?
Chemical Reactions:
The term “ocean acidification” is not entirely accurate; the oceans are actually becoming less
alkaline. The pH of surface seawater has fallen from 8.2 to 8.1, (a pH of 7 is neutral) in a few
hundred years, after remaining constant for millions of years. A decline of .1 pH units may not
sound like a lot, but on the logarithmic scale of pH it translates to a 30 percent rise in acidity.
Seawater pH is projected to drop another .3 to .4 units if carbon dioxide levels reach 800 ppm –
one of the scenarios projected by the Intergovernmental Panel on Climate Change by 2100 –
raising levels of hydrogen ion, H +, 100 to 150 percent (Orr et al., 2005). It could take “tens of
thousands of years” for the chemistry of the oceans to return to pre-industrial levels, the Royal
Society of Britain estimates.
Once dissolved in seawater, CO2 reacts with water, H2O, to form carbonic acid, H2CO3:CO2 +
H2O ↔ H2CO3. Carbonic acid dissolves rapidly to form H+ ions (an acid) and bicarbonate,
HCO3-(a base). Seawater is naturally saturated with another base, carbonate ion (CO3−2) that
acts like an antacid to neutralize the H+, forming more bicarbonate. The net reaction looks like
this: CO2 + H2O + CO3−2→ 2HCO3As carbonate ion gets depleted, seawater becomes undersaturated with respect to two calcium
carbonate minerals vital for shell-building, aragonite and calcite. Scientific models suggest that
the oceans are becoming undersaturated with respect to aragonite at the poles, where the cold
and dense waters most readily absorb atmospheric carbon dioxide. The Southern Ocean is
expected to become undersaturated with respect to aragonite by 2050, and the problem could
extend into the subarctic Pacific Ocean by 2100 (Orr et al., 2005).
A tiny species of zooplankton, the pteropod, called “sea butterflies” for the gelatinous wings they
use to swim around, may be in jeopardy. In an experiment that immersed a pteropod in
seawater with low aragonite levels, part of the organism’s shell was eroded in as little as two
days (Orr et al., 2005).
Over hundreds of years and longer, carbonate ion in the ocean is replenished through the
chemical weathering of limestone rock and dead animals, such as pteropods, that use calcium
carbonate to build their shells. The formation and dissolution of calcium carbonate depends on
the saturation state (Ω) of water, or the ion product of calcium and carbonate concentrations.
The solubility product in the equation, Ω = Ca2+ + CO3−2/K’sp, depends on temperature,
salinity, pressure and the particular mineral. Shell formation usually happens when Ω is greater
than one while dissolution happens when Ω is less than one.
With enough time, calcium carbonate dissolves in large enough quantities to return the oceans’
pH to its natural state which may be why pH in the past did not fall as dramatically as the high
carbon dioxide levels in the past might suggest.
There is some indication that levels of carbonate ion could grow as the oceans warm but
models suggest that this would compensate for only 10 percent of the carbonate ion loss due to
ocean acidification (Orr et al., 2005).
THREE POSSIBLE RESPONSES TO OCEAN ACIDIFICATION:
-Reducing CO2 Emissions.
-Climate Engineering
-Iron Fertilising
-Carbon Negative Fuels
Karey:
http://www.scor-int.org/OBO2009/A&O_Report.pdf
http://www.currentscience.ac.in/Downloads/article_id_076_07_0968_0972_0.pdf
I couldn’t find the exact numbers and components for the Indian ocean so the most i
could find were the general numbers and effects and ways to correct it.
Possible impacts
Increasing acidity has possibly harmful consequences, such as depressing metabolic rates in
jumbo squid, depressing the immune responses of blue mussels, and coral bleaching. However
it may benefit some species, for example increasing the growth rate of the sea star, Pisaster
ochraceus, while shelled plankton species may flourish in altered oceans.[51]
The report "Ocean Acidification Summary for Policymakers 2013" describes research findings
and possible impacts.
Impacts on oceanic calcifying organisms
Although the natural absorption of CO2 by the world's oceans helps mitigate the climatic effects
of anthropogenic emissions of CO2, it is believed that the resulting decrease in pH will have
negative consequences, primarily for oceanic calcifying organisms. These span the food chain
from autotrophs to heterotrophs and include organisms such as coccolithophores, foraminifera,
echinoderms, foraminifera, echinoderms, crustaceans and molluscs. As described above, under
normal conditions, calcite and aragonite are stable in surface waters since the carbonate ion is
at supersaturating concentrations. However, as ocean pH falls, the concentration of carbonate
ions required for saturation to occur increases, and when carbonate becomes undersaturated,
structures made of calcium carbonate are vulnerable to dissolution. Therefore, even if there is
no change in the rate of calcification, the rate of dissolution of calcareous material increases.
Corals, coccolithophore algae, coralline algae, foraminifera, shellfish and pteropods experience
reduced calcification or enhanced dissolution when exposed to elevated CO2.
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 warming by decreasing the Earth's albedo via their effects on oceanic
cloud cover. All marine ecosystems on Earth will be exposed to changes in acidification and
several other ocean biogeochemical changes.
The fluid in the internal compartments where corals grow their exoskeleton is also extremely
important for calcification growth. When the saturation rate of aragonite in the external seawater
is at ambient levels, the corals will grow their aragonite crystals rapidly in their internal
compartments, hence their exoskeleton grows rapidly. If the level of aragonite in the external
seawater is lower than the ambient level, the corals have to work harder to maintain the right
balance in the internal compartment. When that happens, the process of growing the crystals
slows down, and this slows down the rate of how much their exoskeleton is growing. Depending
on how much aragonite is in the surrounding water, the corals may even stop growing because
the levels of aragonite are too low to pump in to the internal compartment. They could even
dissolve faster than they can make the crystals to their skeleton, depending on the aragonite
levels in the surrounding water.
Other biological impacts
Aside from the slowing and/or reversing of calcification, organisms may suffer other adverse
effects, either indirectly through negative impacts on food resources, or directly as reproductive
or physiological effects. For example, the elevated oceanic levels of CO2 may produce CO2 induced acidification of body fluids, known as hypercapnia. Also, increasing ocean acidity is
believed to have a range of direct consequences. For example, increasing acidity has been
observed to: reduce metabolic rates in jumbo squid; depress the immune responses of blue
mussels; and make it harder for juvenile clownfish to tell apart the smells of non-predators and
predators, or hear the sounds of their predators This is possibly because ocean acidification
may alter the acoustic properties of seawater, allowing sound to propagate further, and
increasing ocean noise. This impacts all animals that use sound for echolocation or
communication. Atlantic longfin squid eggs took longer to hatch in acidified water, and the
squid's statolith was smaller and malformed in animals placed in seawater with a lower pH.
However, as with calcification, as yet there is not a full understanding of these processes in
marine organisms or ecosystems.
Non-biological impacts
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
alkalinity, leading to the enhancement of the ocean as a reservoir for CO2 with implications for
climate change as more CO2 leaves the atmosphere for the ocean.
How can I correct it?
Reducing CO2 emissions
●
●
●
Acknowledge that ocean acidification is a direct and real consequence of increasing
atmospheric CO2 concentrations, is already having an effect at current
concentrations, and is likely to cause grave harm to important marine ecosystems as
CO2 concentrations reach 450 parts-per-million and above;
Recognise that reducing the buildup of CO2 in the atmosphere is the only practicable
solution to mitigating ocean acidification;
Reinvigorate action to reduce stressors, such as overfishing and pollution, on marine
ecosystems to increase resilience to ocean acidification.
One policy target related to ocean acidity is the magnitude of future global warming. Parties to
the United Nations Framework Convention on CLimate CHange (UNFCCC) adopted a target of
limiting warming to below 2 °C, relative to the pre-industrial level. Meeting this target would
require substantial reductions in anthropogenic CO2 emissions.
Limiting global warming to below 2 °C would imply a reduction in surface ocean pH of 0.16 from
pre-industrial levels. This would represent a substantial decline in surface ocean pH.
Climate Engineering
Climate engineering has been proposed but substantial research is needed before these
techniques could be applied: “Mitigation approaches such as adding chemicals to counter the
effects of acidification are likely to be expensive, only partly effective and only at a very local
scale, and may pose additional unanticipated risks to the marine environment.” 1
● Iron fertilization
Iron fertilization of the ocean could stimulate photosynthesis in phytoplankton.
The phytoplankton would convert the ocean's dissolved carbon dioxide into carbohydrate and
oxygen gas, some of which would sink into the deeper ocean before oxidizing.
Carbon negative fuels
Carbonic acid can be extracted from seawater as carbon dioxide for use in making synthetic
fuel. If the resulting flue exhaust gas was subject to carbon capture, then the process would be
carbon negative over time, resulting in permanent extraction of inorganic carbon from seawater
and the atmosphere with which seawater is in equilibrium. Based on the energy requirements,
this process was estimated to cost about $50 per tonne of CO2.
1 <http://en.wikipedia.org/wiki/Ocean_acidification#Possible_responses>
Final Paragraphs and Pieces of Work
Isabelle:
The Purpose of the Project
The purpose of this project is to investigate ocean acidification, a growing environmental
concern. By exploring the causes and impacts of ocean acidification, we are able to understand
the issue and examine the different aspects of it. It is evident that the level of acidification varies
across oceans, thus through research, we aim to determine which ocean has the highest level
of acidification. Furthermore, we aim to explore the consequences of this issue, following with
ways in which we can reduce ocean acidification. This project incorporates environmental
sustainability methods to tackle this environmental concern, which will further enable us to
create alternative options and enforce positive change.
Introduction
Ocean acidification occurs when the ocean’s acidity level rises, causing the pH of the ocean to
decrease. The primary cause of this environmental issue is the level of carbon dioxide in the
atmosphere; oceans absorb this greenhouse gas. Carbon dioxide reacts with seawater to form
carbonic acid. Carbonic acid decreases the pH of the ocean water, further decreasing the
alkalinity of the ocean. However, it is vital for the ocean to maintain both an alkaline
environment and a right chemical balance for marine wildlife.
The level of carbon dioxide in the atmosphere has increased significantly in the last few
decades. This is a growing concern that has already impacted the natural environment severely.
The causes of the rise in carbon dioxide levels include human activities, such as burning fossil
fuels. If the level of carbon dioxide continues to rise, the acidification level will also rise. This
issue affects marine ecosystems and organisms intensely.
The rate of ocean acidification is very fast, and it is continuing to accelerate; it is increasing due
to the growing level of carbon dioxide in the atmosphere. Already, 30% of human-generated
carbon dioxide gas emissions have been taken up by the earth’s oceans. It is a serious
environmental problem, as it is changing the natural balance of carbon dioxide in both the
atmosphere and the various oceans.
The Arctic Ocean
The Arctic Ocean is centered in the Arctic North Polar Region, surrounded by Eurasia and North
America. It is the smallest and shallowest ocean in the world. Throughout the year, the Arctic
Ocean is covered by sea ice, however, the surface temperature and salinity vary seasonally.
Due to the changing climate, the Arctic waters have become increasingly vulnerable to factors
such as ocean acidification.
The level of carbon dioxide in the atmosphere has increased significantly in the last few
decades. This is a growing concern that has already impacted the natural environment severely.
Ocean acidification is caused primarily by the uptake of carbon dioxide from the atmosphere,
which decreases the pH of oceans; if the level of carbon dioxide continues to increase, the
acidification level will also increase consequently. This issue affects marine ecosystems and
organisms intensely. Already, regions of the Arctic Ocean are showing effects of acidification.
Although ocean acidification is a global problem, it is apparent that the effect varies per ocean.
Through research, it is found that the Arctic Ocean is among the worlds most sensitive in terms
of its response to climate change; this is explained through the various discoveries that the
Arctic Monitoring and Assessment Programme has made. The rate of ocean acidification is very
fast, and it is continuing to accelerate; it is increasing due to the growing level of carbon dioxide
in the atmosphere. Already, 30% of human-generated carbon dioxide gas emissions have been
taken up by the earth’s oceans. When carbon dioxide dissolves in the surface water of oceans,
carbonic acid is formed. Carbonic acid decreases the pH of the ocean water, further decreasing
the alkalinity of the ocean. However, it is vital for the ocean to maintain both an alkaline
environment and a right chemical balance for marine wildlife.
It is evident that the Arctic Ocean is experiencing widespread effects of ocean acidification.
These effects can be seen in the different seas of the Arctic Ocean. Ocean acidification is
occurring over a wide range of depths in the Nordic Seas. Absorption occurs rapidly in surface
waters, however, it occurs more slowly in deep waters. In Iceland and the Barents Seas, the pH
of seawater is decreasing at a rate of about 0.02 per decade, since the late 1960s. Finally, the
surface waters of the Bering Strait and the Canada basin have also shown some effects. The
notable chemical changes found in surface waters relate to acidification. Although the
magnitudes of acidification in the Arctic Ocean vary, the entire ocean is facing the
consequences of this issue.
The Arctic Ocean consists of cold water; it has a fairly constant temperature of 0°C. Cold
waters, however, have a high capacity to absorb carbon dioxide; it favors the transfer of carbon
dioxide from the atmosphere into the ocean. This further underlines that the rate of carbon
dioxide absorption in the Arctic Ocean is much higher than in any other ocean. As carbon
dioxide is absorbed at a much faster pace, the dissolution of calcium carbonate is promoted.
Finally, the absorption takes place on surface waters; this lowers the pH, creating an acidic
environment.
Furthermore, due to the changing climate, sea ice has been reduced; this creates many open
water surfaces. As more seawater is exposed, more carbon dioxide is able to be absorbed into
the ocean. This may further alter the production and decomposition of organic carbon. Every
year, the amount of open water is growing due to climate change, which is decreasing the Arctic
summer sea ice. If the sea ice continues to melt, the exposure of seawater will expand, allowing
a greater transfer of the greenhouse gas into the ocean, resulting to an increase in the level of
acidification.
The addition of fresh water into the ocean contributes to ocean acidification. Large quantities of
fresh water are supplied from rivers and melting ice, and enter the Arctic Ocean. Fresh water
contains large amounts of organic matter, which will increase the carbon dioxide content in
oceanic water; fresh water dilutes the salinity, alkalinity and carbon content of the ocean,
creating an unbalanced equilibrium of sea water with the atmosphere, thus promoting the
absorption of carbon dioxide until the equilibrium is restored. The Arctic waters are less effective
at chemically neutralizing these acidifying effects.
Conclusion
It is evident that the level of acidification varies across oceans, however, it remains a global
issue. Through comparing and investigating the levels of acidification in the four main oceans,
we have come to the conclusion that the Arctic Ocean has the highest level of acidification; its
response to this issue is also the most severe. The consequences of acidification impact the
marine environment and ecosystems severely, which will further affect communities and
lifestyles that base their income on fishing and other marine animals, as a result. Aware of the
problem, we have identified four key ways to reduce ocean acidification, which include reducing
our carbon emissions, climate engineering, iron fertilisation and carbon negative fuels. Through
researching and learning about ocean acidification, we have understood the severity of this
growing environmental concern, and we will implement these new strategies to reduce
acidification in oceans, in our everyday lives.
Darpan:
The Atlantic Ocean
The Atlantic ocean, the second largest ocean in the world behind the pacific ocean, with a total
area of about 106,400,000 square kilometres. It is bounded on the west of North and South
America.
Ocean Acidification is an ongoing problem in all of the oceans and is caused by the intake of
carbon dioxide (CO2) in the water. Even though the gradual increase of acidity in the ocean is
not the same as it is in fizzy drinks, it still causes problems for the marine environment that have
to adapt to the new acidity in the water.
There are certain figures in which one can measure the amount of acidity, this can be done with
a pH indicator, that follows the pH scale where it goes from 1 to 14, where 1-6 is acidic (1 being
the most acidic), 7 is neutral, and 8-14 is basic (14 being the most basic). And another way of
identifying the acidity levels in the ocean is by measuring the amount of carbon dioxide in the
water, since Carbon dioxide is the main cause of ocean acidification. Carbon Dioxide levels are
measured in micro-atmospheres as partial pressure, which is a common way of measuring the
amount of gas.
The graphs below show the level of Carbon Dioxide and the pH level of the water in the Atlantic
Ocean. The up and down patterns show the influence of seasonal variations.
The graphs show that, as years go by, the amount of CO2 in the ocean increases, as well as
the pH level decreases, which means it becomes more acidic.
The usual levels for pH values in an ocean is about 8.1 and 8.2, and in the last 70 years it has
gone down by 0.2-0.3, which means ocean acidification has increased.
Why is there so much Carbon Dioxide in the atmosphere?
There are quite a few ways in which carbon dioxide is released into the atmosphere, some
examples include fossil fuel powered machines, and the carbon cycle.
The ocean contains about 37,400 tons of suspended Carbon. Reports have shown that half of
the Carbon dioxide suspended in the air is taken in the ocean waters. It is an advantage to
consider that there is less carbon dioxide suspended in the atmosphere, however, it is a huge
disadvantage since abundance of carbon dioxide in the water has proven to alter and damage
marine wildlife, especially those at the bottom of the food chain.
When CO2 dissolves in the ocean it forms Carbonic Acid, which increases the acidity in the
ocean. These levels of acidity have been proven to inhibit shell growth in marine animals
and it is also suspected that these levels are the cause of some disorders in fish.
Unless humans try and stop the emission of CO2 in the atmosphere, sea creatures will have to
learn to adapt to their new habitat that is contaminated and brutally damaged.
In addition, it also harms oxygen levels, since It decreases oxygen levels by killing algae.
Also it decreases immune responses on some organisms as well as causes coral bleaching.
In this video, there is a summary of all the effects of ocean acidification, as well as on animals
and humans. Humans are eating animals that have to breathe and take in carbon dioxide.
https://www.youtube.com/watch?v=Wo-bHt1bOsw
Oscar:
The Consequences of Ocean Acidification
The carbonate systems of all the worlds oceans are change rapidly, due to ocean acidification.
Previous, mass extinction events have been linked to ocean acidification and the current rate of
change in seawater chemistry has never been seen before. Studies suggest that the vast
changes will have great impact on marine life/taxa. Research shows that increased ocean
acidification can potentially have great impact on species distribution and it could very well
propagate through multiple trophic levels of marine food webs. Research into the long-term
consequences of ocean acidification, and long-term impacts on ecosystems is still only in its
early stages.
The debate about CO2 emissions should take into account the risk of irreversible ecosystem
changes, all due to ocean acidification, as well as make it clear that human dependency on
fossil fuels must come to halt before it is too late. Grand investments in clean energy, as well as
actual will from politicians is a necessity to stop climate change and ocean acidification.
Marine food webs in the arctic depend greatly on specific key species such as: sea butterflies,
sea stars, urchins etc, that are very sensitive to ocean acidification and upsetting any of them
could mean significant change to food webs and the ecosystems, for the worse. As there is very
little data on the arctic marine life and how they react to ocean acidification, long term-studies
on the matter are urgently needed, as almost all studies have been conducted in oceans other
than the arctic.
It has been proven that organism growth, and shell formation on some organisms have been
affected by ocean acidification. Some animals grow slower when exposed, however some
seagrass thrive. Birds and mammals out of water do not get affected directly by the acidification,
but if their food source relocates, declines, or other, then it starts to impact them.
In general, its mostly organisms in their earliest stages of life that are the most exposed.
Juvenile and adult fish are believed to be able to sustain the acidification for another century or
so, but fish eggs and early larval stages are the most affected.
Ocean acidification also has economic impacts and consequences. Ocean acidification can
easily affect quality, quantity, and predictability of fish stocks. Fish stocks might be able to
withstand the acidification more if for example overfishing is minimized.
Many coastal communities in the north are likely to be affected by ocean acidification. They fish
and harvest many organisms that get affected, but they may be able to shift over to less
affected species, this might affect cultural practices/traditions however. Like birds and
mammals, residents of these coastal communities are also likely to be indirectly affected by
ocean acidification.
Paul:
The Pacific Ocean
The Pacific Ocean is the world’s largest ocean, with it’s borders reaching from Asia and
Australia all the way to the Americas. The 162.25 million square kilometers of the Pacific make
up around 46% of the world’s water surface. From the Pacific, many industries, such as oyster,
crab and fish industries, make a living from sea creatures and provide food for the general
population.
However, there is a very real threat present to these industries and to everyone who looks to the
Pacific for sustenance - ocean acidification.
For people who look to the Pacific for help sustaining themselves, making a living has become
very hard over the past few years and is expected to become much harder.
“The reason? The rising CO2 emission from our cars and power plants were changing
the chemistry of the sea. This phenomenon know as ocean acidification was always
expected to hit shell creatures hard, but that wasn’t supposed to happen until late in the
century.” - The Seattle Times, Sea Change.
A recent study done by the Pacific Marine Environmental Laboratory (PMEL) showed that sea
creatures, such as the red king crab, to increased CO2 levels, they found that the rate at which
the animals died could affect their entire population. This study, along with many others, proves
as evidence to the horrible dangers of ocean acidification.
Most people who have heard of ocean acidification agree it is a huge threat to both sea
creatures and the humans who live off them, and that it will come upon us late in the century.
The sad and scary truth is, the conditions of ocean acidification have presented themselves
prematurely. A recent study done in Hawaii showed that pH levels in the water have dropped
significantly since 1990 to the current year, 2014, and also that levels of CO2 dissolved in the
same waters are also much greater in 2014 than in 1990.
This data only shows data from the last 24 years, however, scientists have found that, since the
start of the Industrial Revolution, pH levels in the ocean have dropped by 0.1, which is a 30%
logarithmic increase in acidity!
Figures from the IGBP website on the figures of CO2 levels are follows:
“Ocean acidification by numbers:
● 40%: The increase in atmospheric carbon dioxide (CO2) levels since the start of the
industrial revolution.
● 26%: The increase in ocean acidity from preindustrial levels to today.
● 24 million: The number of tonnes of CO2 the ocean absorbs every day.
● 10 times: The current rate of acidification is over 10 times faster than any time in the last
55 million years.”
The ocean serves as a huge sink to absorb the carbon dioxide that we humans produce from
our power plants and other sources such as cars, taking up to one fourth of all that CO2;
however, it has been shown that due to rising temperatures in the ocean and higher pH levels,
the sea is no longer as efficient in absorbing CO2. Also, ocean acidification results in shell
creatures having their shells deteriorate due to the imbalance of carbonate ions in the water.
Many of these organism are large parts of food chains, whether as microorganisms or as food
for humans.
Our Approach to Minimize the Impact of Ocean Acidification
Ocean acidification is a phenomenon occurring globally, and one that will have huge negative
repercussions throughout the world if it is not dealt with. So what are some ways we can
minimize the impact of ocean acidification?
1. Reducing Carbon Dioxide Emissions
First and foremost, we must reduce our carbon footprint. The ocean has always been the
world’s great carbon dioxide sink; however the rising CO₂ levels have caused the water to
become more and more acidic, so lowering the emission of this overly-abundant gas seems to
be the most logical solution.
Ways that we can reduce our carbon footprint are:
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Reducing the amount of distance traveled by car, or car pool if you must. Cars produce
the highest amounts of CO₂ due to their proliferous use today. If possible, try avoiding
cars altogether, using bicycles to travel.
Replace incandescent light bulbs with brighter, more eco-friendly LED bulbs. Save the
world, and the ocean.
Eat less red meat! This is surprisingly effective in reducing our footprint.
Turn off the lights when you’re not in the room; it’s simple but the amount of electricity
wasted due to this apparent triviality.
More extreme measures would include:
● Solar panels! Use plenty of them to power your house rather than relying on carbonburning plants.
● Support other forms of clean energy.
2. Climate Engineering
One method that could possibly help with ocean acidification is climate engineering, which also
works by reducing carbon in the air, but not as simply as turning off the lights. More specifically,
however, Solar Radiation Management, which involves reflecting the heat from the sun back
into space, rather than allowing them to stay trapped inside the greenhouse gas layer of Earth.
Companies such as Platinum Roofing can help change roofs of buildings so that they reflect
solar heat and rays with ease.
3. Iron Fertilisation
Iron fertilisation involves adding iron to the ocean, which results in prodigious amounts of
plankton in that area. In theory, these plankton would use the carbon dioxide in the water to
photosynthesise and convert it into oxygen. At the same time, the reaction would cool down the
Earth’s temperature, increasing once more the ocean’s ability to retain dissolved carbon dioxide.
Nonetheless, iron fertilisation is highly unreliable due to the fact that a) it’s efficiency is unknown
and b) the consequences it could result in are unpredictable.
4. Carbon Negative Fuels
Carbonic acid is extracted from seawater as CO2 to make synthetic fuels. If the resulting flue
exhaust gas is subject to carbon capture, then the process will become carbon negative over
time, where permanent extraction of inorganic carbon from seawater and the atmosphere with
which seawater is in equilibrium. A big disadvantage of this process would be considered the
affordability, based on the energy requirements for the technology, this process was estimated
to cost about $50 per tonne of CO2.
Karey:
The Indian Ocean
The Indian Ocean, the world’s third largest oceanic division, covers over 20% of the water on
the Earth. It bounds Asia on the north, Africa on the west, Australia on the east, and also the
Southern Ocean on the south. . At the same time, due to its borders with the middle east, it is
also one of the oceans worst affected by global warming.
Over the past 300 million years, ocean pH has been slightly basic, averaging about 8.2. Today,
it is around 8.1, a drop of 0.1 pH units, representing a 25% increase in acidity over the past two
centuries.
The acidity of the Indian Ocean is believed to be contributed by the long-range transport of
gaseous pollutants such as SO2 and NO2 from the Indian subcontinent, by the north-east trade
wind. This have caused impact such as ocean calcification, on not only the Indian Ocean but
every other ocean in the world. As the ocean pH falls, whereas it gets more acidic, the
concentration of carbonate ions required for saturation to occur increases, and when carbonate
becomes undersaturated, structures made of calcium carbonate are vulnerable to dissolution.
The rainwater over the Indian Ocean is also observed as acidic (pH<5.6) across the InterTropical Convergence Zone.
The acidic components in the Indian Ocean are mainly sulphate, which may have been
produced during SO2 oxidation. Non-sea salt SO4 and non-sea salt Ca were also very high,
especially near the continent.