Tuesday, August 27, 2013

Winter in Antarctica

Hi Sea Fans!

I got to do Winter in the Antarctic too...thanks to Sabrina!  Becs left for warmer weather in the UK and I stayed behind to see what goes on when it's REALLY cold!!

When it's cold and windy...it's REALLY COLD AND WINDY!
Every person who stays over winter gets to go camping for a week away from base.  These are the only holidays that the staff get to go on.  I went with Sabrina and Malcy and we ran into some nasty weather.  We didn't mind though, we snuggled up in the warm tent and played games and read books...a good way to relax! 
I'm getting ahead of myself though, I still have some photos from the end of summer:
CTD being winched up. (In other words, a mini crane-type thing is used to let the CTD down and pull t back up again).
I went out with Sabrina to do a CTD cast.  This is when a special piece of equipment with sensors, attached to a line, is dropped down to 500m below the water.  It measures salinity (how salty the water is), temperature and depth.   A fluorometer (tells how much phytoplankton is in the water) and PAR sensor (this measure the amount of sunlight available for the phytoplankton) are also attached.

Typical CTD results for Summer are:
* high surface temperature
* fluorescence (due to large numbers of phytoplankton - the plant plankton)
* high levels of sunlight
* low salinity (melting snow, ice and sea ice means lots of freshwater to dilute the salt)

Typical CTD results for Winter are:
* low surface temperature (sea water freezes at a lower temperature than fresh water because of the salt in it)
* low fluorescence (in winter there is not enough sunlight for the phytoplankton to grow)
* low levels of sunlight (sometimes there is NO SUNLIGHT!)
* high salinity

On our trips out we also got to explore the ice from the boat.

There are lots of different kinds of ice:

  • the really thick ice where even humans can walk is called FAST ICE,
    Photo: Barbara Wienecke
  • the ice I'm sitting on in the photo above the fast ice is called BRASH ICE.  There are lots of bits of ice that float on top of teh water and get pushed around by the wind and ocean currents.
  • Check out http://www.antarctica.ac.uk/about_antarctica/geography/ice/index.php for more...
I must run Sea Fans, more to come soon so stay tuned! : )
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