Saturday, 18 April 2009

Past South Georgia and onto Polar Front

Icebergs again, plenty around South Georgia after few in the open water north of South Orkneys

Now tied up at Fipass in the Falklands so will catch up with the happening of the last couple of weeks (or at least the more photogenic aspects - I'll spare you the physics cruise report, which is possibly the dullest piece of writing I'll ever produce. We got to the Georgia Basin, the site of the South Georgia bloom (fertilised by iron coming from the island and/or shallow shelf around the island) and the end of our transect - a line north-east(ish) from South Orkneys to west of South Georgia. The aim of the transect was to sample different environments along the way - from ice and Antarctic Peninsula influenced water to the south, through 'open water' (low iron as not downstream of land) and into warmer and South Georgia influenced water to the north. This year has been very warm - 1.5 degrees Celcius warmer than the same time last year. Not sure yet why it is so different but will be an opportunity to see what effects the temperature has (but also cause some problems comparing between this autumn and the summer cruise last year).

After two stations in the bloom we set off for the Polar Front to see why King Penguins go there, swimming for several days through areas with seemingly higher productivity (plant growth). The Polar Front is a transition zone between Antarctic and Sub-Antarctic water masses, a region of strong currents and also an important habitat zone in its own right. Most people define it as a single line rather than a two-dimensional area so I was hoping to use finding the King Penguins and Grey-headed Albatrosses all lined up to identify the front! As it was we had to rely on my satellite work and a series of eXpendable BathyThermographs (XBTs) to get us to a suitable bit of the Polar Front. We had to hove to and do nothing the first night as there was too much swell - we have to deploy the nets at night or otherwise the fish see it coming and swim away. However, in a break with the past couple of years we could work the next couple of nights, getting three net hauls done per night and hopefully some interesting insight into the myctophid fish (penguin food) of the area. Then it got rough again - force 10 for a day. We managed to run slightly across the wind and tack back to South Georgia to do the Bird Island base relief call (pick up summerers, give food and other supplies to the winterers). See next post.

Windy, but it got windier. Force 9-10 winds aren't too bad - not dangerous and you know you're not going to work for a bit so can relax for a bit and watch some films.

What you get for steaming across the swell.

One of these happened to fly past - young (3years?) Wandering Albatross. They stay at sea until they are seven, then attend the colony and display for a few years and start breeding at 10-12.

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