Opinion Sur Joven

When we were kids we’d see it as a giant, endless thing. We found out what “the horizon” was thanks to that infinite line that marked its virtual end, very far away. We can see it wearing deep blue, translucent turquoise or brownish green dresses, but it’s always the same: the sea, the main character in so many vacations, stories and tales. It’s both vital and omnipresent.

Seas and oceans account for 71% of the Earth’s surface (about 140 million square miles), and are an even greater source of biological and natural resources than rainforests. The sea is the essential regulator of the terrestrial weather and represents an economic resource, a transportation route and an energy source reserve. 40% of the global population lives less than 100 miles away from the shores, and 35 million people depend on fishing activities.

But today the sea is in danger and cannot avoid the consequences of global warming. Its temperature may rise, and that would have a dramatic impact on the planet. Oceans are essential to absorb carbon dioxide, thus preventing said compound from accumulating in the atmosphere, which would consequently rise the global surface temperature.

Carbon, acidity and deserts

“The ocean is getting warmer: both sea-surface and deep-water temperatures are higher than they were fifty years ago”, said Alberto Piola to Opinión Sur Joven. He’s the head of Argentina’s Naval Hydrography Service Research Department, a researcher and a professor at UBA (University of Buenos Aires).

Out of the total carbon dioxide increase in the atmosphere, which is both generated by natural causes and man’s activities, a portion stays in the atmosphere and the rest is absorbed by other parts of the system, the ocean being one of them. Piola calls it a “geochemistry effect”. He explains that “said absorption regulates the weather; if the entire accumulation remained in the atmosphere, the greenhouse effect would be twice as harmful”. The main carbon dioxide absorber agent is the phytoplankton, which is the formal name for microscopic algae. “The problem is that, when the ocean has a higher carbon dioxide concentration, the acidity if the water increases and that affects organisms such as clams, mussels, crustaceans and corals”, adds Piola.

Water acidity affects biodiversity in tropical regions and may cause some species to disappear. According to research papers submitted at a convention organized by the UNESCO Intergovernmental Oceanographic Commission (IOC) , this acidity alteration could damage the seas’ trophic webs (food chains) and change the biological, geological and chemical composition of the oceans.

It could even end up generating the so-called “sea deserts”. Deserts are growing not only on the continental surface as a consequence of desertification and deforestation, but the crisis is even deeper… so deep that they’re expanding towards the bottom of the sea. Since the water has less oxygen, the phytoplankton ends up doing an inverse photosynthesis process and oxidizes its organic matter, thus rotting in the sea. “When the water has low oxygen levels, fish die. It’s a dramatic situation”, Piola warns. This usually happens in areas with organic sewage waste: it turns into food for these plants, which could become a plague. For example, the Mississippi river mouth in the Gulf of Mexico is affected by this phenomenon”, Piola comments.

In hot water

Marcos Sommer is a Doctor of Science and a firm activist at Oceanógrafos Sin Fronteras (in English, oceanographers without borders) , an NGO promoting awareness on the health of our oceans. “80% of the heat absorbed by the planet ends up in the seas. Therefore, any temperature variation may bring devastating consequences, because the oceanic system directly controls global weather”, he said to Opinión Sur Joven.

On the other hand, he warns that “60% of the responsibility for the sea level increase has to do with temperature increase”. That is, when water gets warmer, it expands and grows. Of course it’s only a few millimeters, which we could barely notice in our kettles. Therefore, not only do we have the ice cap melting problem, but global warming itself is pushing the sea limits inwards.

Sommer -who was born in Argentina and currently lives in Kiel, Germany- points out that today the Arctic ice cap is half as thick as it used to be thirty years ago, and the area covering the ice cap has shrunk about 10%. If the melting process continues, the ice in that region could be totally gone by 2070.

So what problem could melting cause, apart from flooding our cities? “Glacier water is fresh, and once it mixes with the salt water of the ocean, we lose it. Otherwise, a really expensive process is necessary to recover it”.

The problem with fishing

Overfishing is another problem affecting our seas. “Almost 80% of the ocean’s fishing reserves are being extracted to the point of their biological limit; drift nets are destructive and ruin their reproductive habitat”, says Sommer, who also assures that the fishing rhythm and quantity is three times higher than fish reproduction.

Today the fishing industry earns 34,000 million dollars a year and employs 150 million workers worldwide, making this problem even more difficult to solve.

In that sense, Sommer believes the world should rethink the way economic growth is being measured. “For a long time now, the priorities of development have been focused on what mankind can extract from the ecosystems, without really analyzing how this affects the biological base of our lives”.

However, when asked how things can be improved, he focuses on the civil society. “It must make a stronger and more professional democratic demand every day for all of us to live in a truly sustainable environment”. Evidently, governments won’t do it for us.