Posts Tagged ‘[lang_en]Ocean acidification[/lang_en][lang_fr]Acidification des oceans[/lang_fr]’

Sigourney Weaver, Ocean Acidification, Avatar, and the Belo Monte dam

Tuesday, January 4th, 2011

Sigourney Weaver is one of my favourite actresses. I first saw her as Ellen Ripley in Alien, when I was at college, and have enjoyed most of the films I’ve seen her in since.

I don’t know if it was “Gorillas in the Mist: The Story of Dian Fossey” that set her on the road to environmental awareness, but whatever got her started, she is definitely a powerful voice for the protection of our world.

Her most recent blockbuster movie, Avatar, has certainly helped throw her into the spotlight in this role, together with its director, James Cameron. Even before that film came out, she was using the publicity it was attracting to divert attention to another film, for which she is the narrator. “Acid Test: The global challenge of ocean acidification” is a Natural Resources Defence Council documentary about what has been called “global warmings’ ugly sister”, the chemical changes in the ocean that are being caused by all that CO2 we are adding to the atmosphere.

Fox News wanted to interview Sigourney about her role in Avatar, even starting the interview with some trailers from the film. But she wanted to talk about Acid Test instead, and completely took control of the interview! It’s worth watching, she was clearly not going to be put off her stride by the hosts. One could almost feel sorry for them, but me, I enjoy seeing Sigourney in those ‘Ripley’ moments!

Now, she’s turning her attention to the Belo Monte dam. This is a hydroelectricity generation project which is planned to be built on the Xingu river, in the Brazilian Amazon. She has narrated a video which describes the impact of the dam (also shown here), and invites us to sign a petition to the Brazilian government to encourage them to cancel the project.

Dams which provide hydroelectric power are widely considered to be ecologically friendly things, so why does she think this one is bad?

Well, there are several reasons. One is that this will become the third-largest dam in the world, and the environmental impacts will be correspondingly huge. Building this dam will require moving more earth than was moved to create the Panama canal, and will block almost the entire flow of the river. An area equivalent to a circle 29 km across (18 miles) will be inundated.

Native peoples will have their way of life destroyed, obviously. It’s not surprising they rely heavily on the river for transport and fish, and that they farm much of the land that will be flooded by the dam. Ecosystems will be totally destroyed too, with several species that live only there doomed to extinction.

Of course, not all species will suffer, malaria mosquitos are expected to thrive in the new expanses of still water.

The dam is also destined to be one of the least efficient in the world. During the dry season, it will produce only one tenth of its maximum capacity. The annual average output will be less than 40% of the nominal capacity. In order to raise the efficiency, the Brazilian government needs to construct more dams upstream, to control and regulate the flow of water all year round. In fact, there are more than 60 large dams planned for the amazon basin over the next 60 years. That’s a staggering number!

Many people are hoping for a sequel to Avatar. For the people of the Xingu river, if the Belo Monte dam gets built, there will be no sequel, their world will be gone. So if you can spare 10 minutes, take a look at the video. Then, if you agree with me that this dam is a bad idea, please sign that petition!

World Oceans Day, June 8th

Saturday, June 6th, 2009

The Aegean

The Aegean

Next Monday, June 8th, is World Oceans Day. At the risk of turning this blog into a diary of global eco-events, I’d like to draw your attention to it.

The idea to have a world-day for the oceans came in 1992 from Canada, at the Earth Summit in Rio de Janeiro. It’s been celebrated every year since then, but this year marks the first time it has official U.N. recognition. Henceforth, World Oceans Day will be celebrated on June 8th, every year.

You might think that since I live near Geneva, about as far away from the sea as it is possible to get in Western Europe, I would not have much to say about the sea. If you think that, you must be new to this blog (welcome!), the sea is one thing I can talk about for hours. I grew up in England, closer to the coast than most people there. Nobody in England is more than 70 miles from the sea, I grew up much closer than that, about one mile away from the shore, on an island, no less. I spent many a childhood summer day freezing in the cold water, picking my way over the stony beaches, trying to see what I could through the opaque grey-green waters of the north Kent coast (not much, as it happens). I collected foraminifera (tiny shells, less than 1 mm across) and looked at them under a microscope. I remember the first time I saw sea-anemones, on the beaches of Jersey on a family holiday. I’ve seen octopus and nudibranchs on crowded Greek beaches, and sharks and dolphins in the Maldives. Oh yes, I can safely say I love the sea.

The oceans are huge. They cover almost three-quarters of the surface of the earth, and something like three fifths of the earth is over a mile below the surface of the sea. There is an awful lot of seawater out there. So why do we need a world-day event to draw attention to the oceans? Well, as it turns out, the seas and oceans of the world are not in good shape, and it’s our fault, again. You can find out more about the threats to the oceans on the Marine Conservation Society website, here are a few of the highlights.

Everyone knows about global warming, and the melting of the polar ice-caps. That’s bad news for penguins and polar bears, but also for people. A large fraction of humanity lives near the coast, making a substantial part of their living from what they can haul out of the sea. Rising seas and warming waters will change that. Not only will islands and low-lying regions be lost under the waves, the ecosystems at the coastal fringes will suffer too. Coral reefs, for example, provide living space and nurseries for a great many species, and are essential to the marine environment. Even creatures that don’t live on or in them directly often depend on the animals that do. Excessively warm water leads to ‘coral bleaching’, which can kill it if the water stays warm for long enough. Bleaching events are more common than they used to be, and are predicted to become much worse over time. Despite some research showing that some corals may adapt to warmer waters, there is strong reason to believe that most corals will be killed by warm seas by the end of this century unless we make big cuts in our emissions of greenhouse gasses. Scientists are working to find ways to help coral survive, but they’re racing against the clock.



Globally, there’s an even bigger threat, ocean-acidification. The oceans absorb a great deal of the excess carbon dioxide that we are pumping into the atmosphere, and this is slowly turning the seas more acidic. This slows coral growth because it is harder for the coral to form its chalky skeleton. Other creatures, many of which are right at the bottom of the marine food chain, will suffer the same fate. Acidification of the oceans is a global problem by its very nature. It will affect reefs and other ecosystems worldwide, not just those near to cities and industries.

Overfishing is another major problem for the oceans. By depleting stocks of even a few species, we change the way entire ecosystems behave, often seriously. Tuna have been fished almost to extinction in the Mediterranean sea, and there is little sign that common sense will prevail to reduce the pressure on them. Tuna are predators, high up in the food chain. When you remove top predators, often the result is that a few species lower down the food-chain start to dominate, out-competing other creatures. The ecosystem becomes unbalanced, and may change its nature completely. It may not be enough to simply stop hunting the predators, the ecosystem may no longer be able to recover on its own.

Floating garbage is another serious problem. On the tiny atoll of Midway in the Pacific ocean, albatross often mistake floating plastic garbage for food, which they then feed to their chicks. That kills many of them, not surprisingly. Albatross aren’t meant to digest golf-tees, toothbrushes, and lego blocks.

Even the efforts we go to to protect the oceans and their inhabitants can often be misguided. I’m sure we’ve all heard of dolphin-safe tuna, it even got a mention in Lethal Weapon 2, released some 20 years ago. I’m fond of dolphins, like many people, but I was shocked to learn about just how much damage dolphin-safe tuna-fishing can do. The methods used to catch tuna without harming dolphins have a much higher rate of bycatch than other methods. ‘Bycatch’ is another word for ‘collateral damage’, animals accidentally killed while hunting a specific species at sea. Much of the bycatch in dolphin-safe tuna is in itself seriously endangered, far more so than dolphins themselves. No, dolphin-safe tuna is not a good thing for the marine environment.

Sunset on the Beach

Sunset on the Beach

More and more people are becoming aware of and involved in environmental issues. They are paying attention to the environmental cost of the goods they purchase, insisting on packaging that can be recycled, lower power consumption from electrical goods, or higher mileage from their cars, for example. But what can you change in your daily activities to help the oceans, especially if you live far from the sea? The Marine Conservation Society have some advice, and there’s also a page of hints at The Ocean Project. One obvious thing is to be more informed and cautious in your seafood purchases, both sites have suggestions there. If you prefer to avoid seafood altogether, simply buying organic food is a good idea. That encourages farmers to produce more of it, which means less pesticide in use. Reduced pesticide use means less of it getting into our rivers and from there into the sea, finally ending up in marine mammals like that dolphin we were trying to save a moment ago.

You can find out more about World Ocean Day at the World Ocean Network site. Maybe one of the events that they list is taking place somewhere near you. If not, there are plenty of web-based resources available, like the 24 hours in the Ocean online event from the Musée Nausicaä. I’ll certainly be following that for some of the day.