Ocean acidification is the continuous reduction of the ocean’s pH, carbonate ion concentration, and saturation states of biological calcium carbonate minerals. Ocean acidification is caused by the uptake of carbon dioxide from the atmosphere. According to “Ocean Acidification: The Other CO2 Problem,” after the industrial revolution, carbon dioxide levels in the atmosphere has increased nearly 40%, primarily due to the burning of fossil fuels and deforestation (Doney S. 2009).
The increase of carbon dioxide is dangerous because an estimated 30%- 40% of atmospheric carbon dioxide dissolves into the ocean, lakes and rivers ( Feely. 004). Thus if the atmospheric carbon dioxide concentration increases, so does the concentration of carbon dioxide in the ocean.
When the seawater absorbs an excessive amount of carbon dioxide the chemistry of the seawater changes a process called ocean acidification in which the pH decreases and the acidity of the seawater increases. The Chemistry Behind Ocean Acidification Ocean acidification becomes a problem, if the water absorbs an excessive amount of carbon dioxide at a higher rate than normal. When carbon dioxide ( CO2) reacts with water ( H20), carbonic acid ( H2CO3) is formed.
Carbonic acid, then releases Hydrogen ions (H+), which bonds with other molecules in the surrounding area. Specifically, some of these hydrogen ions (H+) combine with carbonate ions ( CO3-2) and Bicarbonate (HCO3) ions are formed. Thus ocean acidification decreases carbonate ions; This causes a problem for marine ecosystems, because carbonate ions are essential factor to marine life. The acidity of seawater is determined by the amount of hydrogen ions in solution , which is then measured on the pH scale. The higher the concentration of hydrogen ions in a solution, the lower the pH of the solution.
As stated in the previous paragraph, carbonic acid ( CO3-2) releases hydrogen ions ( H+) into the solution. If the sea water absorbs more carbon dioxide and then more carbonic acid will be formed as well. Which means the ocean will releases large quantities of hydrogen ions. Thus lowering the pH of the ocean. “ Ocean acidification: A greater threat than climate change or Overfishing,” reports that since the industrial revolution the pH of the ocean has dropped from 8. 2 to 8. 1. This change in the pH of water over the past 150 years is the greatest seen over the past everal million years. ( Burner W. 2008 )
Environmental Impacts Ocean acidification impacts the marine Ecosystems, specifically marine calcifying organisms, including oysters, clams, sea urchins, shallow water corals, deep-sea corals, and calcareous plankton. Calcifying organism requires Calcium Carbonate (CaCO3) to grow their shells. When the pH of seawater decreases, the concentration of carbonate ions is reduced as well. So if there are less carbonate ions, it become more difficult to form calcium carbonate (CaCO3).
All calcifying organisms require calcium carbonate(CaCO3) to grow their shell. When shelled organism are in danger it causes problems with marine resources and services. Since our society heavily relies on shelled organisms for primary protein source, energy, medicine and water. According to PBS “ Coral reefs Die as Ocean Temperature Rises, Water Acidifies,” 100 marine station in Florida have had a 44% decline of coral reefs in the past twenty years . In the Caribbean’s the numbers are even worse , the decline is up to 80% in over the past three decades (Camp. J, Director, 2012).
Chris Langdo, a marine scientist at the University of Miami says, that the coral reefs have been struggling to adapt due to a range of problems. The biggest problem that the coral reefs face is the increase of carbon dioxide in water. Carbon dioxide makes the temperature water rise which makes the coral reefs bleach or expel their colorful algae that lives in their tissue which exposes their skeletons. However, the rise of CO2 not only increases the temperature of the water, but changes the acidity levels as well.
However, the rate of changing the water acidity is happening at a higher rate than normal, which makes it difficult for the marine organisms to adapt to these changes. Although marine organisms are highly adaptable creatures but the the process of adapting takes time. Finally acidification in marine animals makes their skeletons weak and brittle. Thus the more acidic the water the harder it is for coral reefs to grow their skeletons. Which makes them more susceptible to diseases throughout their lives. Benefits of Ocean Acidification
Originally, scientist only focused on the benefits of ocean acidification, mainly that the ocean removed the greenhouse gas carbon dioxide from the atmosphere. Also, there are certain species such as photosynthetic algae and sea-grass that could potentially benefit from the increase of carbon dioxide; Since, carbon dioxide is mandatory for the survival of this species just like it is for plants on land . None the less, an excessive amount of carbon dioxide absorbed by the ocean changes the chemistry and affects marine ecosystems.
Many researchers have studied ways in which the effects of ocean acidification could be decreased or stopped. The Intergovernmental Panel on Climate Change stated that if carbon dioxide emissions continue to increase, the ocean acidity could rise up to 150% by 2100. We can decrease emissions by burning less fossil fuels such as coal, natural gas, and oil; These fossil fuels are used as energy for different means of transportation and are also used to generate electricity, and to carry out different industrial processes.
Therefore, it would be best to explore other transportation alternatives such as walking, jogging, biking and electrical vehicles. Also, it’s recommended to replace the incandescent bulbs with CFLs (compact fluorescent lights). CFLs require less energy than the traditional incandescent bulbs, it also gives the same intensity of light. Carbon dioxide is one of the main chemicals that causes the greenhouse effect, it is naturally present in the carbon cycle. However, human activities are causing negative impacts and contributing to an altered cycle.
According to The Environmental Protection Agency,provides some strategies and suggestions for reducing carbon dioxide. First of all it would be best to improve the insulation of buildings to reduce energy consumption. Second, conserve energy by “Reducing personal energy use by turning off lights and electronics when not in use, which reduces electricity demand. Also, reducing travel distance in vehicles reduces petroleum consumption. ” Lastly, “producing more energy from renewable sources and using fuels with lower carbon contents can reduce carbon dioxide emissions.
Some other things that are being done to reduce the effects ocean acidification has on the environment is educating the public on things they can do in their everyday lives. NOAA Ocean Acidification Program aims to “Build knowledge about how to adapt to the consequences of ocean acidification and effectively conserve marine ecosystems as acidification occurs” Some crucial steps taken to assist in the educating the public was discussed earlier such as using fuel-efficient vehicles, replace light bulbs with CFL’s, limit fertilizers used in home gardening project.
Another step we can accomplish as a community is to eat more fish that are significantly harvested as this contributes to “genetic diversity which will help us resources respond and adapt to the changing world, as advised by The National Resource Defense Council. More studies are required in order to understand all the potential risks involved with ocean acidification. One thing is certain all disciplines of science agree that ocean acidification is a major problem and requires continuous efforts and research.
Further research can prevent irreversible damages that can occur to our ecosystems and environment. Tom Bell a marine biochemist states “all agree that it is important to recognize that marine organisms will be affected by environmental changes and that this may impact the climate in return. CO2 that is absorbed by the ocean is still climate-relevant”. So, even just a minor shift in pH can have drastic impacts and must not be overlooked.
