Wednesday, 1 February 2017

How the Doctor got a Bird Island T-Shirt

Peat is more interesting than you’d think. Not only can it be used to flavour whiskey, but with a bit of ingenuity it can also tell us a lot about the world around us. One of the scientists, Angela Gallego-Sala, is particularly interested in what it can tell us about the carbon cycle. Peat represents plant matter which grew and then died in water saturated environments like wetlands or bogs. Whilst the plants were growing they trapped the energy of the sun and used it in conjunction with carbon dioxide to create glucose or sugar. This traps carbon inside the plant. Under normal circumstances, this carbon is returned to the atmosphere as carbon dioxide when the plant dies and decays. In peatlands, things are slightly different. As the plant matter in peatlands decays, it does so in an environment which is saturated with water and thus starved of oxygen. The decomposition of the plant matter is therefore a lot slower and most of the carbon stays safely locked away in the partially decomposed plant matter.

This may all sound terrifically familiar to anyone interested in fossil fuels. And that’s because it’s pretty much the same stuff. Peat is just a few million years off turning into lignite coal. It’s still used as a fuel around the world. People in areas that are extremely low on trees have always tended to use peat to fuel fires instead. This is why Scottish and Irish whiskies have that distinctive smoky flavour; the malted barley used to make the spirit is dried over peat fires.

Peatlands are extremely efficient carbon sinks. Any carbon dioxide emitted by the decay of plant matter is used in photosynthesis by plants living at the surface. Peatlands tend to work as net-extractors of carbon dioxide from the atmosphere. Not only that, but they allow us a window back in time. Because the plant matter falls in layers and the deposition is very slow (peat layers form in millimetres each year), taking core samples of peat enables us to see what plants flourished thousands or hundreds of thousands of years ago. And we can also extrapolate what conditions might have been like at those times.

Angela’s research is attempting to outline certain aspects of climate that may impact on the carbon cycle- in particular wind speed. As winds move around the Southern Ocean they find little in the way of land masses to impede their progress. As such they pick up enormous amounts of sea spray and deposit it on any land masses that they encounter. This means that in times of greater wind speeds, more salty water is deposited on the land.

Angela’s team have noted that certain species of testate amoebae live in the peatlands. Different communities of amoebae will flourish at different levels of salinity. Core samples of the peat will therefore contain different communities of amoebae depending on how salty the peatland was when that layer of peat was being formed. This can then be carbon dated and we can work out what wind speeds would have been like at the time when the peat layer was formed. Why is this important? Well, when wind speeds and currents align, the southern ocean has a tendency to stop being a carbon sink and instead releases carbon into the atmosphere again. So if we can establish under what circumstances this is liable to happen, we can predict in future when we might lose the safety net which the southern ocean carbon sink provides.

This was a very long winded (but hopefully interesting) way of saying that Angela and her team will spend the next few months island hopping in the Sub-Antarctic islands. She’s working in conjunction with French, Russian and American scientists who are likewise attempting to map out the carbon cycle in the southern ocean. And all this meant that I got to visit Bird Island which is clearly the most important aspect of the whole thing! 
Bird Island
 Bird Island lies just off the North Western tip of South Georgia and has had a BAS research station there since 1957. It was spruced up a few years ago and now consists of about 3-4 buildings all in the tasteful muted green that BAS seems to like! It’s only accessible by sea and the jetty is in fairly shallow waters which meant that we had to approach in the Humbers (little power boats). I had been asked if I wouldn’t mind popping in to answer a few questions on medications (Bird Island does not get their own doc, you see, just a team of advanced first aiders) and first aid protocols. Trying my hardest to rein in a massive smirk, I said that it would be a hardship, but I would see what I could do. And despite the fact that I got into the world’s biggest boat suit which made me look a bit like a telly tubby mated with an astronaut, the day was a triumph!

We shot forward into a wall of low-lying cloud which eventually parted to expose the station and the bay in which it lives. The barks of seals filled the air, as did the reek of salty, fishy decomposition that impregnates the island! Our little boat dodged around floating rafts of kelp and rounded a rocky promontory on which seal pups crawled anxiously calling out for their mothers. Smooth and sleek adult seals jetted through the waters near the boat, hunting for prey in the grey-green waves. A photo at this point would have been wonderful but I regret that I was otherwise engaged in clinging on for dear life.
Fur seals frolicking in the water (photo taken by Sara Labrousse)

At the jetty, there was a massive welcome party. We were escorted towards the base and I was impressed by the nonchalance with which our hosts shooed the fur seals out of our way whilst the furries barked at us, exposing their questionable dental hygiene. These little charmers are quite aggressive during the mating season and seal bites are very liable to get infected. Even the pups seemed to learn grumpiness early on, with tiny little seals growling at me as I went past.
The welcoming party  (photo taken by Sara Labrousse)

Great teeth on a furry  (photo taken by Sara Labrousse)

We were given tea and cookies (chilli and chocolate cookies- absolutely amazing!) and then I cracked on with helping with the first aid stuff. But not before I’d issued the most important command “I don’t have much time. Quick, go get me a Bird Island t-shirt!” Must-Be-Branded.
Most important job achieved- a T-shirt! Excuse the smirk- I struggle with selfies!

It was great and the time passed all too quickly. But soon enough I had to scuttle back outside, along the metal walkway that the fur seals have decided to colonise and onto my little boat. Angela and her team were left behind to do their research and we bounced back along the crests of the waves to the ship. As we were winched up to the deck the sun came out, burning away the mists that covered the island. It was possible to see the birds that give the island its name, swarming about the cliff face and livening the air with their cries.  
Being winched aboard  (photo taken by Sara Labrousse)

Ak- the birds!

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