Given Jules Verne's deep interest in science and the unknown, and his eagerness to pass this enthusiasm and sense of mystery to young and old, I can't help but wonder how he would react if he could see us now. If scientists are correct, we may well be adversely impacting creatures we've never even laid eyes upon, let alone classified."The deepest parts of the ocean are totally unknown to us,"... "What goes on in those distant depths? What creatures inhabit, or could inhabit, those regions twelve or fifteen miles beneath the surface of the water? It's almost beyond conjecture."
The ocean is full of pending discoveries
Jules Verne (1828–1905) published the French equivalents of these words in 1869, and little has changed since. 126 years later, a Time cover story on deep–sea exploration made much the same admission: "We know more about Mars than we know about the oceans." - from the introduction to Jules Verne's "Twenty Thousand Leagues Under the Sea"
The Southern Ocean has been absorbing less CO2 from the atmosphere since 1981, even though levels have increased 40 percent due to burning of fossil fuels. Oceans absorb half of all human carbon emissions, but the Southern Ocean is taking up less and less and is reaching its saturation point, reported an international research team in the journal Science.I know what you're going to ask - "why do they mention the 'Southern Ocean' in particular?" Here's the scoop:This is the first evidence of the long-feared positive feedbacks that could rapidly accelerate the rate of climate change, pushing impacts to the extreme end of the scale. - IPS
Carbon dioxide in the atmosphere can dissolve in water, and the colder and more turbulent regions of the oceans tend to absorb carbon dioxide, while the warmer and less turbulent regions release it, carbon dioxide being less soluble in warm water than in cold water. - Institute of Science in SocietyThe IPS article mentions one obvious impact of oceans reaching a CO2 saturation point - my paraphrased summary being that we're losing an enormous, and free, CO2 offset machine.
As dire as this may be, it doesn't stop there. In nature, nothing is linear. Another consequence of excess ocean CO2 levels is increased ocean acidification.
Ocean acidification is the name given to the ongoing decrease in the pH of the Earth's oceans, caused by their uptake of anthropogenic carbon dioxide from the atmosphere. Between 1751 and 1994 surface ocean pH is estimated to have decreased from approximately 8.179 to 8.104 (a change of -0.075) - WikipediaThere are, of course, implications to this acidification trend:
- As ocean pH falls, so does the concentration of carbonate ions, and when carbonate becomes under-saturated, structures made of calcium carbonate are vulnerable to dissolution. A vast array of ocean creatures rely on the calcite or aragonite polymorphs of calcium carbonate to construct cell coverings or skeletons (Wikipedia).
- Many forms of sea life extract carbon and oxygen from seawater and combine them with calcium to produce calcium carbonate (CaCO3). This is used to produce shells and other hard body parts by a variety of organisms, such as coral, clams, oysters and some microscopic plants and animals. When these organisms die, their shells and body parts sink to the seabed. Over very long periods of time, enormous numbers of dead organisms can create thick layers of carbonate-rich deposits on the ocean floor. - Schlumberger
Another effect of global warming is a reduction in the upward movement of the nutrient-rich deeper stratum - with implications for one of the most important ingredients in our 'biological soup': phytoplankton.
Global warming of the surface layers of the oceans reduces the upward transport of nutrients. Computer simulations predict that plankton growth will become unstable when the supply of nutrients is reduced.... Plankton plays a key role in the oceans. It forms the basis of the marine food web. Moreover, phytoplankton (microscopically small algae) consumes the greenhouse gas carbon dioxide during photosynthesis. Because the oceans cover more than 70% of the earth’s surface, marine phytoplankton is quantitatively important for reducing the greenhouse effect on earth. Phytoplankton growth depends on light and on nutrients such as nitrogen and phosphorus. These nutrients are supplied from deeper ocean layers, and are slowly mixed upwards. In large parts of the oceans, phytoplankton is concentrated at about 100 meters depth. Phytoplankton grows well at this depth, because there is a sufficient supply of light from above and a sufficient supply of nutrients from below.... However, warm surface layers reduce mixing of the ocean waters. This vertical stratification of the water column is widespread in the oceans. A larger temperature difference between two water layers implies less mixing of chemicals between these water layers. Global warming of the surface layers of the oceans, owing to climate change, strengthens the stratification and thereby reduces the upward mixing of nutrients. - Global Warming could Destabilize Plankton in OceansIt must be said that the interactions of oceans, and ocean life, are a relatively new study. Not enough is known to pretend to give a half-decent picture of the potential reactions to climate change by the vast oceans and the creatures that inhabit them. If our experience of terrestrial environments (which, in themselves, are still full of mystery) is anything to go by, however, then there will be no quick fix to restoring equilibrium to the sea.
Phytoplankton absorb Carbon Dioxide and release Oxygen. In fact phytoplankton produce as much Oxygen as all the trees in the world, and they remove 3 billion tonnes of Carbon Dioxide every year. - SAHFOS
The global importance of phytoplankton cannot be overstated. - NASA
For phytoplankton to thrive there must be an appropriate supply of nutrients. Too little, and the phytoplankton will fail to grow, too much all at once from agricultural runoffs sewage or other industrial pollutants, and algal blooms will result that could become toxic to fish, livestock and humans eating shellfish that feed on the phytoplankton and accumulate the toxins. Moreover, the water must not be too warm, or too acid. All these conditions are deteriorating on account of global warming, bringing the prospect of a collapse in the marine biota, and turning the oceans into a massive carbon source that would further aggravate global warming.... - Institute of Science in Society
Oceans are vast, deep, and mysterious. They cover 71 percent of the earth’s surface and contain approximately 97 percent of the earth’s water. The average depth of the ocean is almost 4,000 metres, and nearly half the area is over 3,000 metres deep.The oceans are home to the majority of plant and animal life on earth, accounting for 90 percent of the world’s living biomass, and many new species are being discovered from the depths. The Census of Marine Life (COML), an international alliance of scientists from 70 countries, discovered some 13 000 new species in 2003 alone. - Institute of Science in Society
Excerpt from BBC's "Creatures of the Deep" Duration: 8 mins
CO2 absorption by our oceans is a natural part of the great carbon cycle. It is - like many other pieces of this huge, interdependent jig-saw puzzle that is our biologically diverse world - yet another service to humanity that we tend to take for granted, until we begin to lose it. If the world is our host, and we are its guests, our activities over the last century are a serious breach of etiquette. We have overstepped our bounds. And, if our own needs must take precedence in this discussion, let's not forget that the ocean's great bounty directly nourishes untold millions of our own species.
A natural carbon equilibrium is being tipped out of balance, and we would do well to take heed. There is an ocean of unknown out there.
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