Human activities have led to an exponential increase in the use of fossil fuel. The benefits of using fossil
fuels are short lived in comparison to its long-term negative effects. In the last couple of decades, the major
consumption of fossil fuel played a significant role in the rise of concentration of CO2 in the atmosphere.
Roughly two trillion metric tons of CO2 have been emitted in the atmosphere and over a quarter of these
got mixed with the ocean water resulting in ocean acidification (Buffie and Carr, 2010).
Ocean acidification is the decrease of pH in the oceans due to absorption of CO2 in the atmosphere (Fabry,
2008). Over the past three hundred million years ocean pH levels have been 8.3, however in the past 200
years the pH level of oceans’ have reduced to 8.1, an increase of 25% in the acidity level (Bednaršek, 2012).
The CO2 in the ocean reacts with water to form carbonic acid and consume carbonate ions. As a result a lot
of marine species are suffering high mortality rate, lower reproduction and the disruption of ecosystems
and food chains. Moreover, over 22 million tons of carbon dioxide goes to the ocean every day (Buffie and
Carr, 2010). If the rate of CO2 emission in the ocean is not reduced, the predicted ocean CO2 concentration
will be 200% by the end of this century (Buffie and Carr, 2010). This paper will explain two major lines of
evidence for ocean acidification. The first evidence is based on the impacts of acidity of ocean on calcifying
organisms and the second one is acidosis and impact of CO2 on the physiological process of marine species
(Silver Sunbream Fish). Lastly the paper will also touch on the potential pitfall correlated with the conducted
experiments, which might have hindered
The Effects of Increased Atmospheric CO2
Deforestation and the burning of fossil fuels have led to a great increase in anthropogenic carbon dioxide
released into the atmosphere. Since the Industrial Revolution, the concentration of atmospheric CO2 has
increased from about 280 parts per million to above 390 parts per million; and recently has been calculated
to be rising 1.5-2 parts per million per year (Kudela, 2013). This sharp increase in atmospheric CO2 has had
an impact on the ocean, and can be seen by the increase in the levels of gaseous CO2 in the seawater.
When the CO2 rich atmosphere comes in contact with the surface of the ocean, CO2 is readily absorbed
which causes the pH of seawater to become more acidic. Many enzymes and processes that occur in the
ocean, like test building, are pH sensitive (Calderia, 2003).
The Role of Climate Change in Coral Reef Destruction
Results from Different Studies Investigating the Role of Climate Change in Coral Reef Destruction Evidence
of Sea Acidi... ... middle of paper ... ...igher—Can We Do Anything AD. (200Resilience and climate change:
lessons from coral reefs and bleaching in the Western Indian Ocean. Estuarine, Coastal and Shelf Science ,
63, 353–372
The Acidification of the Ocean off California’s Coast
At its most basic, climate change is the result of previously unheard of levels of carbon dioxide entering the
atmosphere and creating a greenhouse effect within the earth’s atmosphere. This causes the average
temperature of the planet to increase over time. The full effects of this kind of temperature increase are still
being explored, but it is already clear that our planet is being harmed as a result. Ocean acidification is an
extension of global climate change. It is the result of about a third of the carbon dioxide in the air seeping
into the earth’s oceans.
Carbon Dioxide Intake of Oceans
INTRODUCTION The level of carbon dioxide has increased tremendously over the past few years by nearly
40%, that is from approximately 280ppm in preindustrial times to 384ppm in 2007(Solomon et.al 2007).
Nearly one third of anthropogenic carbon dioxide is being absorbed by the oceans today(Science Daily, May
24, 2008) . Uptake of carbon dioxide by the oceans is not a harmful phenomenon , but excess of it leads to a
reduction in pH thereby altering the fundamental seawater chemistry, commonly known as ocean
acidification . This rising levels of atmospheric carbon dioxide is mainly due to anthropogenic activities such
as burniig of fossil fuels , chopping and burning down tropical forests for new agricultural lands and tourism
purposes,etc. are taking place at large scales , thereby releasing enormous amounts of carbon dioxide gas in
the atmosphere.The total human carbon dioxide emissions amounts to approximately 560 billion tons.
The Impact of Global Warming on Oceans
The study done by this team came to the conclusion that ocean temperatures below 300 meters have been
raised a tenth of a degree Fahrenheit since the 1950s. Also, closer to the surface, ocean waters have
increased in temperature by about 0.5 degrees (Pawelski, 2000). The principal author of this study and chief
of National Oceanic and Atmospheric Administration’s Ocean Climate Laboratory, Sydney Levitus, said,
“These temperature changes may seem small, but they represent very large changes in heat content of the
ocean, and this heat will eventually find it its way back to the atmosphere.” (Pawelski, 2000). Thus, although
these temperature changes in the ocean seem small, they can have quite a large effect on our Earth’s
atmosphere. Levitus also mentions that a large portion of global warming that seems to be absent in our
atmosphere is actually in our oceans.
What's Causing Ocean Acidification?
Ocean acidification is defined as “…the perturbation to the ocean carbonate system directly caused by
ocean uptake of anthropogenic carbon dioxide (CO2) emissions to the atmosphere.” (Turley) Overtime, our
oceans have become more acidic due to rapidly evolving technology and a growing dependence on fossil
fuel. In fact, our “oceans have become 26% more acidic since the start of the Industrial Revolution.”
(Cullinane) Unfortunately, this acidity continues to rise and “…the pH of surface oceans…is projected to drop
another 0.3–0.4 pH units by the end of this century, [which] has not occurred for more than 20 million years
of Earth's history.” (Guinotte) Why our oceans today so acidic and what can we to control these pH levels?
Some studies have found “that atmospheric CO2 concentration is approximately 383 parts per million by
volume (ppmv), a level not seen in at least 650,000 years, and it is projected to increase by 0.5% per year
throughout the 21st century.” (Guinotte) “This is because…the ocean absorbs about a third of fossil fuel
emissions, but this amount is likely to increase to 90% in the future.” (Bralower) As a result, “the chemistry
of the world's oceans is changing at a rate not seen for 65 million years, with far-reaching implications for
marine biodiversity and food security, according to a new United Nations study...” (Knight) “…This change is
cause for serious concern [for] many marine organisms…, [because they] may not be able to adapt quickly
enough to survive these changes.” (Guinotte) Over the last century, [it is evident that] the current levels are
beginning to impact organisms that make their shells out of the minerals aragonite and calcite…” (Bralower)
“Coral reef[s] are highly vulnerable to ocean acidific... ... middle of paper ... ...ion-Background." EARTH 103:
Earth in the Future.
Ocean Acidification
About 30% of CO2 emissions are taken up by the oceans today (Freely et al. 2004) and this percentage will
continue to rise if nothing is done to prevent it, potentially leading to enhanced levels of ultraviolet
radiation at the earth’s surface (Harley, C. D. G., et al, 2006). While many marine organisms have adapted to
thermal fluctuations in the last few million years, the expected changes in pH are higher than any other pH
changes inferred from the fossil record over the past 200–300 million years (Caldeira & Wickett 2003;
Feelyet al. 2004). The following diagram represents the effect of greenhouse gas emissions on the oceans
causing increased CO2, decreased pH, sea level rise, storm frequency and potential upwelling.
The Sea of Change: An Increase in Ocean Acidification
Ocean acidification, which refers to the reduction of pH levels in the ocean is caused by an uptake of carbon
dioxide from the atmosphere. (NOAA) Ocean acidification alters the ocean’s chemical makeup creating a
slightly more acidic pH level; this process has very severe consequences for not only ocean water but for the
marine life that reside there. If current levels of carbon dioxide continue to follow trend than the ocean we
know today could be reduced to an acidic pool to harsh for most ocean life as we know it. But even slight
changes in the pH balance can have catastrophic effects on marine life. For example, only a .1 decrease in
ocean pH has caused 10% of the Great Barrier Reef’s coral coverage to die off.
The Effects of Oil Spills and Drilling on the Environment
This would cause the pipe to burst, which has a high probability of leading to oil being spilled. The average
number of marine spills per year has increased from 47 per year (1968-1977) to 188 ruptures and 228
leakages per year (Jernelöv 2010). Oil spills are detrimental to the environment, and every year, about 1% of
the oil being shipped across the ocean (around 1.5 billion tons of oil) is spilled (Jernelöv 2010). One
particular article mentions that there are two types of spills: shore-bound surface spills and the deep-ocean
oil spills.