Science in the arctic: deploying mescosms at 79°N

Posted by jamie — 9 June 2010 at 1:44pm - Comments

Like many other marine species, pteropods are threatened by ocean acidification © Cobbing/Greenpeace

Janet Cotter, from Greenpeace's Science Unit is currently on board the Esperanza on the first leg of the Arctic Under Pressure expedition. The ship is currently in Ny-Ålesund in the arctic, where Janet has been helping seagulls from 'contributing' to ocean acidification research.

In my day job, I work as a scientist as Greenpeace's Research Laboratories in Exeter, which is part of the Greenpeace's Science Unit. We might not get do the banner hanging from bridges and all the dramatic stuff that other Greenpeace activists do, but we have an important role in the organisation.  We analyse samples from around the world in our laboratories, often looking for toxic contamination of soils, rivers and seas, or sampling foodstuffs for GM contamination.

Alongside writing papers, reports and briefings, we attend UN and other international environmental meetings to impress on politicians the importance of the scientific evidence so that any international agreements provide real protection for the environment.

For example, our recent work on reducing carbon emissions from deforestation has stressed the scientific importance of conserving natural forests to the ongoing UN negotiations to reduce the impact of climate change. Otherwise, the decisions made in the negotiations risk encouraging the conversion of natural forests to plantations for commercial crops like palm oil and paper. As most scientists agree, such conversion will not help the climate and risks losing valuable biodiversity.

Janet Cotter from Greenpeace's Science UnitBut right now, I'm on board the Esperanza in the arctic, where I'm helping out on some important experiments into the effects of a process known as ocean acidification. The ship is at the tiny international scientific research base of Ny-Ålesund, only 1200 km from the north pole, in the Norwegian archipelago of Svalbard. This is my first time in the arctic and I'm finding it a little strange to think of my friends back home, lying on the beach whilst I'm surrounded by snow!

Ny Ålesund is the most northerly settlement in the world, at very nearly 79°N. It's an old coal mining village nestled amid dramatic scenery featuring mountains, glaciers and fjords. The coal mining ceased in the early 1960s following a tragic accident and the village has since reinvented itself as a research village housing scientists studying the arctic.

Since the late 1960s, the number of scientists coming here and the number of countries they come from has increased enormously, especially during the summer months - currently there are about 100 scientists living here. This has created a mini 'scientific village', with the scientists and laboratories from each nation housed in one of the old buildings from coal mining days. These include the Chinese building, the British building, the Norwegian building, the Indian building, the French-German building. It's almost a mini United Nations.

Not only are the scientists from a diverse range of countries, but they also concentrate on equally diverse disciplines including geologists, glaciologists, atmospheric chemists, and plant, mammal and bird specialists. Everyone dines together in a central building and they tell me this is where the most fruitful exchanges and scientific advancements are made - over coffee.

Over the last week, the Esperanza, and all of us on board have been working hard with our friends from the German marine research institute IFM-GEOMAR (a prestigious institute of marine science based in Kiel, Germany) to deploy nine big mesocosms in Kongsfjord, just offshore from Ny-Ålesund. These mesocosms are large structures, about 17m high, consisting of a frame that holds a large bag enclosing 50 tonnes of seawater containing all different kinds of microscopic life.

One of the things I've been doing is helping the scientists prepare roofs for the mesocosms before deployment. I was intrigued: why do the mesocosms need roofs? The reason, as I found out, is because otherwise seabirds - like the glaucous gulls, fulmars and kittiwakes that live in Kongsfjord - can land in the mesocosms. Attracted by the fluorescent orange colour of the mesocosm structures (which apparently look like fishing boats) they think they might get a free meal.

A mesocosm for measuring the effects of ocean acidification

One of the mesocosms being prepared for the ocean acidification experiments © Cobbing/Greenpeace

Unfortunately, the birds can either get stuck in the mesocosms, or their excrement inadvertently fertilizes the experiment, which would wreck the results. The roofs look very much like umbrellas, but we fixed rows of 10cm long spikes all around the outside to deter the the birds from landing. They certainly don't look very comfortable to sit on, so hopefully the seagulls will also find them unattractive.

Using the ship's crane, each mesocosm was carefully lowered into the approximate position about 200m from the shore in a sheltered part of the bay. Then the scientists used a smaller boat to tow each mesocosms and then attach them to anchors that had earlier been placed on the floor of the fjord.

For the experiment, the nine mesocosms will be acidified to different levels using CO2 enriched water (made here in Ny Ålesund by bubbling CO2 through seawater), which will reflect the range of of atmospheric CO2 concentrations that are predicted to occur in the future.

Ocean acidification results from increased CO2 in the atmosphere and, like climate change, is caused by burning fossil fuels and deforestation. As CO2 concentrations in the atmosphere continue to rise, increasing amounts of CO2 are dissolving into the oceans. The CO2 combines with seawater to form a weak acid, causing the chemical balance of the seawater to shift from its natural state towards being less alkaline - this is ocean acidification. This, in turn, causes other important changes in ocean chemistry.

Over the next few weeks, the scientists will be taking daily samples from the mesocosms and subjecting them to intense biological and chemical analysis to determine the changes caused by this artificial acidification.

One of things they'll be looking for is any effects on marine plankton, as acidification is expected to cause a drop in the abundance of carbonate ions, the basic building blocks for these organisms. Research on this issue is in its infancy and although the ocean chemistry is well understood, the impacts of acidification on marine organisms and food webs are less clear.

Plankton, at the bottom of the food chain, are a vital component of this food web, so effects on them will be seen further up the food chain. So that's why I'm here getting my hands dirty looking at plankton.

About Jamie

I'm a forests campaigner working mainly on Indonesia. My personal mumblings can be found @shrinkydinky.

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