Ocean Acidification Could Cause Many Species To Go Extinct

coral reefBy John Lawrence

As the amount of carbon dioxide pumped into the atmosphere continues to increase, a certain portion of that gets absorbed by the oceans. This year alone some two and a half billion tons of CO2 will be absorbed by the oceans. That represents seven pounds pumped into the seas by every American.

Oceans cover seventy percent of the earth’s surface, and everywhere the oceans and the atmosphere come into contact there is an exchange of gases. When this exchange is in balance, there is no problem. But when the atmosphere’s gaseous composition has been changed, which it has since the industrial revolution, the exchange becomes lopsided. More COgoes into the ocean than comes out.

Since the start of the industrial revolution, humans have burned through enough fossil fuels to add 365 billion metric tons of carbon to the atmosphere. Deforestation has added another 180 billion tons. Each year we add another nine billion tons or so, and that amount has been increasing 6 percent annually. Today the concentration of carbon dioxide in the air is 400 parts per million (PPM). This is higher than it has been at any time in the last 800,000 years.

If current trends continue, the concentration of carbon dioxide in the atmosphere will be 500 ppm by 2050, double the levels in pre-industrial days. So in a sense, all the progress that civilization has made due to the expenditure of large quantities of energy since 1850 or so has now essentially doomed civilization unless radical changes are made in how this energy is obtained and utilized.

When carbon concentrations reach 500 ppm, there will be a global temperature rise of between three and a half and seven degrees Fahrenheidt. This will trigger world altering events such as the loss of all glaciers, melting of the Arctic ice cap and a sea level rise that will inundate all coastal cities and low lying islands. Already some low lying islands have disappeared. The President of Kiribati is in talks with Fiji’s military government to buy up to 5,000 acres of land in order to relocate the 102,697 people that live in his country.  President Tong said that this is their last resort: “Our people will have to move as the tides have reached our homes and villages.”

pH is a measure of the acidity or basicity of an aqueous solution. Solutions with a pH less than 7 are said to be acidic and solutions with a pH greater than 7 are basic or alkaline. Pure water has a pH very close to 7. Thanks to all the extra CO2, the pH of the oceans’ waters has already dropped from an average of 8.2 to an average of 8.1. A drop of .1 means that the oceans are now 30 percent more acidic than they were in 1800.

If business continues as usual, the surface ocean pH will drop to 8.0 by 2050 and to 7.8 by century’s end. At that point the oceans will be 150% more acidic than they were at the start of the industrial revolution. Marine biologists like Jason Hall-Spencer have warned about the catastrophic consequences to marine life if the oceans’ pH reaches 7.8. According to him this represents a tipping point at which the ocean’s ecosystems start to crash.

The ones most at risk are the calcifiers. The term calcifier refers to an organism that builds a shell or external skeleton or, in the case of a plant, an internal scaffolding out of the mineral calcium carbonate. Some examples of calcifiers are starfish, sea urchins, clams, oysters and barnicles. Some species of coral and seaweed are calcifiers. Ocean acidification increases the difficulty for organisms to perform the calcification process in the process of their development. At higher levels of acidification, already existing organisms start to dissolve.

Ocean acidification is dangerous because it will change the makeup of microbial communities. It will interfere with photosynthesis because it will change the amount of light passing through the water. It will also alter the way sound propagates and make the seas noisier. It will promote the growth of toxic algae. There will be a reduction in biodiversity. Microscopic organisms will use up more nutrients leaving less for larger organisms. The equilibrium of the oceans established over many eons becomes unhinged, and many organisms will go extinct.

coral reef 2Eventually, the oceans will reach their capacity to absorb carbon dioxide. At that point the build-up of atmospheric carbon dioxide will accelerate. So far roughly one third of the carbon dioxide that humans have spewed into the air has been absorbed by the oceans – approximately 150 metric tons. Most importantly, it’s the rate at which this process has taken place. This amount has gone into the oceans in just 150 years – a minute measure compared to the eons at which most geophysical changes take place. The current acidification is on a path to reach levels higher than any seen in the last 65 million years, and the rate of increase is about ten times the rate that preceded the Paleocene–Eocene mass extinction. The current and projected acidification has been described as an almost unprecedented geological event.

The oceans’ rising acidfication dissolves shellfish in the Pacific northwest that many Indian tribes depend upon:

It’s a big challenge to tribes in the Pacific Northwest, said Billy Frank Jr. (Suquamish) back in 2010, addressing the 20 tribes that make up the Northwest Indian Fisheries Commission

Its impacts are felt by Native and non-Native communities in Washington State that rely on oysters and shellfish. Disastrous production failures in oyster beds caused by low pH-seawater blindsided the oyster industry in 2010, prompting a comprehensive 2012 investigation by Washington State. Earlier this month Governor Jay Inslee took the issue to the media in order to jump-start climate change action in his state, The New York Times reported on August 3 [2014].

The Quinault Indian Nation on Washington’s coast is part of one of the most productive natural areas in the world and is especially involved in the ocean acidification issue. The rivers in Quinault support runs of salmon that have in turn supported generations of Quinault people. The villages of Taholah and Queets are located at the mouth of two of those great rivers. The Pacific Ocean they flow into is the source of halibut, crab, razor clams and many other species that are part of the Quinault heritage.

shellfishThe Great Barrier Reef (GBR) off the coast of Australia is in trouble. The largest coral reef system in the world is not growing like it used to. The growth of colonies has slowed by approximately 13% since 1990. Although protected as a marine park for decades, more than half of the coral is dead. Without concerted action, just five to 10 percent of the coral will remain by 2020, according to a 2012 scientific survey.

According to Scientific American:

The most likely reason is climate change caused by increasing carbon dioxide (CO2) and other greenhouse gases in the atmosphere…

The burning of fossil fuels over the past century or so has driven atmospheric CO2 levels from 280 parts per million (ppm) to [400] ppm—and growing. More than 25 percent of this extra CO2 is absorbed by the world’s oceans and reacts with seawater to form carbonic acid. A rising carbonic acid level means a more acidic ocean.

In 1981 UNESCO declared the GBR a World Heritage Area, calling it “an irreplaceable source of life and inspiration”. It was home to 10 percent of all fish on the planet. But now Australia is proposing to dump 5 million tons of toxic dredging sludge in the region as they go about building a port for the export of coal. Given the perilous health of the reef, which is also facing enormous threats from rising water temperatures and ocean acidity due to CO2 emissions from fossil fuels, scientists are calling for a complete ban on dumping in the GBR or anywhere near it.

The additional threat posed by coal ports and other industrial developments along the coast is so serious that UNESCO warned Australia it would change the reef’s prestigious World Heritage Site designation to a “World Heritage Site in Danger”.

The UNESCO decision is expected mid-2015, which is also when the dredging is scheduled to begin.

We are running geologic history backwards at warp speed. In the magazine Oceanography, Kump and Ridgwell have observed: “It is the rate of CO2 release that makes the current great experiment so geologically unusual, and quite possible unprecedented in earth history. [If this rate continues, it] is likely to leave a legacy of the [current era] as one of the most notable, if not cataclysmic events in the history of our planet.”


John Lawrence

John Lawrence graduated from Georgia Tech, Stanford and University of California at San Diego. While at UCSD, he was one of the original writer/workers on the San Diego Free Press in the late 1960s. He founded the San Diego Jazz Society in 1984 which had grants from the San Diego Commission for Arts and Culture and presented both local and nationally known jazz artists. His website is Social Choice and Beyond which exemplifies his interest in Economic Democracy. His book is East West Synthesis. He also blogs at Will Blog For Food. He can be reached at j.c.lawrence@cox.net.


  1. avatarWill Falk says

    “Without concerted action, just five to ten percent of the coral will remain by 2020.”

    Time is short.

    thanks so much for the article, John.

  2. avatarBill Adams says

    I think there is a generational aspect to this, with Boomers milking the earth to maintain their lifestyle before they exit the planet. Of course, the generations that follow are being robbed. I don’t think we’ll see the urgency or policy shifts until the young mobilize on a massive basis. Occupy offered hope, and showed a large minority of Boomers were willing to assist. It got snuffed out by strong police action everywhere. It’s surprising to me there has been no second act. I believe any strategies for change must focus on mobilizing the young.

  3. avatarBill Adams says

    Ooops, my comment was intended for “DIY Resistance: Develop a Sense of Urgency” by Will Falk

    • avatarBill Adams says

      For the record, I’m a boomer too, and there are many boomers that care about the planet. However, boomers make up the large majority of climate change deniers and Tea Party activists.

  4. avatarGrace Rich says

    We all are robbing a livable planet from our children and grandchildren. The best chance we have is to cut our energy use about 80% which basically would put us back into an farming economy without many comforts including our precious AC! How many are willing to do this? I would but I and my family would have to live in a different locale but it would be rough for all of us living “the comfortable life” including we baby boomers. When things get really disasterous we may all be willing but by that time it will be too late……oh well species come and species go I hope there are other dimensions we can go to Tragic

  5. avatarMiner49er says

    The oceans as a whole are highly alkaline–not acidic. The degree of alkalinity has varied, but the oceans have always been alkaline. It is simply not possible for 0.04% ambient CO2 in air to acidify the oceans. It is also impossible for alkaline water to dissolve oyster shells.

    At first these vapid articles about “ocean acidification” purported that “acid” waters were dissolving oyster shells. After it became evident that that is impossible, the ankle-biters switched to alleging harm to oyster larvae. So, after a hilarious false start, this meme is wearing a little thin.

    While the oceans do absorb a large quantity of CO2 from the air, that CO2 is promptly converted to limestone (CaCO3) and other carbonate rocks, partly by the actions of oysters, clams, mussels, coral and other shell-forming animals, as well as direct and plant processes. Carbonate rocks are the ultimate repository of CO2 in earth’s ecosystem. And, by the way, the dissolved CO2 is “carbonic” acid–not carbolic” acid. Carbonic acid is promptly converted to carbonate rock.

    Local acidification of seawater is possible. It occurs naturally because of sea floor thermal vents and volcanic eruptions. It can also occur because of human caused discharges of polluted water. Agriculture is the most common source of such discharges, followed by municipal waste. Agricultural discharges are completely unregulated and are practically invisible to the regulatory bureaucracy. The Toledo OH algae bloom is evidence of this.

    None of the articles on this subject (including the “scholarly” articles) specify what kind of acid is allegedly harming oysters. It it came from from CO2, it could ONLY be carbonic acid (H2CO3), which most people know as carbonated water. Other acids, such as nitric acid (thunderstorms & human activity), sulfuric acid (geothermal & human activity), hydrochloric (stomach) acid (industrial & human activity). One would hope that all those do-gooder researchers would at least bother to collect & analyze samples of the offending waters.

    States and the oyster industry should look closer to home for their acidification problem.

  6. avatar says

    Perhaps, Miner 49er, you should check out these authoritative writings that disagree with your analysis:

    “The Biology of Coral Reefs,” by Charles Sheppard, Simon K Davy and Graham M Pilling published by Oxford University Press 2009
    “Coral Reefs May Start Dissolving When Atmospheric CO2 Doubles,” by Jacob Silverman et al, Geophysical Research Letters 35 (2009)

    You are right about one thing though. The oceans are still basic. However, they are getting less basic, and this is what is causing problems.

    And you might state what scholarly articles you have written since you claim to be an expert on the subject.

  7. avatarFrank Thomas says

    I fully agree with you , John.

    The chemistry of how CO2 reacts with seawater and carbonate ions to create carbonic acid and resultant ocean acidification is well understood. Increased CO2 levels reduce ocean pH, carbonate ion concentration and saturation levels of critically important calcium carbonate minerals. As is also well known, the shells or skeletons of many marine organisms — urchins, clams, mussels, oysters, deep and shallow water corals, coccolithophorids, calcareous plankton, etc.) — are made of calcium carbonate (in calcite or aragonite forms), and the shells dissolve when carbonate ion concentrations dwindle with rising ocean acidification. Studies clearly show that the calcification ability of many organisms to produce shells or skeletons decreases as acidic ocean water beomes less saturated with calcium carbonate minerals.

    As you note, the lower the pH of ocean water, the higher the acidity. A pH value below 7 indicates an acid, and a value above 7 indicates an alkali. The pH scale is logarithmic, so an outwardly small decrease of 0.1 equates — as has happened over recent decades since the Industrial Revolution — equates to an enormous 30% increase in acidity! If currently high CO2 levels continue, studies show we can expect a 150% to 170% increase in ocean acidity by 2100, destroying a major source of humanity’s primary source of protein. Over 24 million tons of CO2 are going into the ocean every day. There comes a balance point when the ocean will not absorb any much more CO2. This means planet surface temperatures will shoot up significantly unless we drastically bring down our CO2 emission levels.

    There’s no doubt about the scientific evidence. Our planet is truly at risk of an ominous environmental breakdown from many directions. The upcoming IPCC report makes that perfectly clear.

    The other key fact you address is how FAST this is all happening.

    First is the 40% increase in atmospheric CO2 levels since the Industrial Revolution (285 ppm to +400 ppm today) of which 80% of this increase (90 ppm) has occurred since 1960. Then there’s the 30% rate of increase in ocean acidity over same period which is 10 times higher than the mass extinction of deep sea organisms and massive changes to the surface ocean ecosystem that took place 55 million years ago! See: “Ocean Acidification” : Summary for Policymakers – 3rd Symposium on the Ocean in a High CO2 World, 2013, UNESCO and SCOR (Scientific Committee on Ocean Research).
    In the words of the recent UNESCO-SCOR report,

    “The incredible speed of change in ocean acidity along with other ocean stresses such increased seawater temperatures — that are accelerating in Arctic waters, thereby enhancing risk of huge methane emissions — deoxygeneration, pollution, extreme events, overexploitation, etc., are all acting together to make matters worse. For example, the combined effect of unusual warming and ocean acidity are a significant threat for warm-water corals, particularly tropical coral reefs.

    The increase in atmospheric CO2 is occurring too quickly to be stabilized by natural feedbacks such as the dissolution of deep-sea carbonates, which acts on time-scales of thousands of years, or the weathering of terrestrial carbonate and silicate rocks, which operates on time-scales of tens to hundreds of thousands of years.

    Global-scale projections of the changing chemistry of seawater can be made with high accuracy from scenarios of atmospheric CO2 levels. Even if anthropogenic CO2 emissions stopped today, the ocean’s pH would not recover to its preindustrial level for centuries.”

  8. avatarFrank Thomas says

    I should note that the phrase in the 7th paragraph: … that are accelerating in Arctic waters, thereby enhancing risk of huge methane emissions … are my words, not SCOR’s words.

  9. avatarSatya Nandlal says

    Hi John;
    Thanks for highlighting about Kiribati. It will be intersting if you can provide examples of islands that have disappeared due to increase sea level ….as you said ‘Already some low lying islands have disappeared.’