Marine life at risk

Was just last week the world celebrated Ocean Day. Now comes a study noting the peril facing our oceans. Warming waters, ocean acidification, the spread of oxygen-free dead zones, habitat loss, and overfishing are pushing the world’s oceans toward a phase of mass extinctions not seen in millions of years

In a report sponsored by the International Programme on the State of the Oceans (IPSO), the scientists said that the rates of coral loss, fish stock depletion, open-water “dead zones,” and toxic algae blooms have surpassed even the worst-case projections of just four years ago.

And these trends could portend significantly wider disruptions on the world’s marine ecosystems; all five mass extinctions in the planet’s history — the most recent of which occurred 55 million years ago — were preceded by similar ocean conditions, scientists say.

The group called on states, regional bodies and the UN to establish programs to better conserve ocean ecosystems — particularly in the largely unprotected high seas that make up most of the planet’s oceans — and to reduce the greenhouse gas emissions driving ocean acidification and rising sea temperatures.

It means that not only on land but also in water which covers a major part of our planet, humans have managed to cause considerable damage. Oceans play a far more greater role in stabilising climate, and when we tamper with their ecology, we can expect the worst. For it doesn't take the bootstrap theory of particle physics to understand the interconnectedness of things here on earth!

When water acidifies...

The acidification of the world's oceans could have major consequences for the marine environment. New research shows that coccoliths, which are an important part of the marine environment, dissolve when seawater acidifies.

Acidification of the oceans is a serious problem. The acidification has enormous consequences not only for coccoliths, but also for many other marine organisms as well as the global carbon cycle.

Coccoliths are very small shells of calcium carbonate that encapsulate a number of species of alga. Algae plays an important role in the global carbon-oxygen cycle and thus in our ecosystem.

The study by the Nano-Science Center, University of Copenhagen, showed how acidification affects the coccoliths. They are protected from dissolution by a very thin layer of organic material that the algae formed, even though the seawater is extremely unsaturated relative to calcite.

The protection of the organic material is lost when the pH is lowered slightly. In fact, it turns out that the shell falls completely apart when we do experiments in water with a pH value that many researchers believe will be the found in the world oceans in the year 2100 due to the CO2 levels.

Everything is connected to something in the world wide web of life. A rip in the web can cascade into chaos down the line. But do we care? Wouldn't seem so, with the attention now turning to natural gas and shale deposits that pose their own dangers.

The invisible spill

The new official flow rate of oil from the spill caused by collapse of the Deepwater Horizon rig in the Gulf of Mexico at 60,000 barrels a day means there's enough oil to flow for two to four years!!

But hopefully the leak rate will fall sharply over time once the natural gas in the reservoir is exhausted. That is the driving force.

The oil spill is a good time to imagine what’s spilling into the atmosphere and oceans in an invisible manner since decades – imagine the damage from carbon dioxide being added to the atmosphere at a rate of about 1,000 tons a second!

A new paper in the journal Science, by researchers at the University of Queensland and University of North Carolina talk of large impacts on marine life and ocean dynamics caused by the ongoing buildup of carbon dioxide, both by warming the planet and changing ocean chemistry.

Ocean systems are being driven toward conditions not seen for millions of years, with an associated risk of fundamental and irreversible ecological transformation. The impacts of anthropogenic climate change include decreased ocean productivity, altered food web dynamics, reduced abundance of habitat-forming species, shifting species distributions, and a greater incidence of disease among marine life.

While we see the oil spill, we cannot see the ‘carbon spill’ and hence remain unmindful of the irreversible change we have induced.