August 01 - Buoys and CTDs
Update (01st August 2004)
Noon Position : lat 63° 05.5' N, long 40° 53.4' W
Air temperature @ noon today : 6.6°C
Sea temperature @ noon today : -0.5°C
Ice and Sunshine: The week in brief.
Ice and sunshine off the coast of Greenland: our view this morning:
Today has been a "pinch me I'm dreaming" sort of day. After a week of (seemingly) endless gales, grey sky and rain, we awoke to blue skies, bright sunshine and glorious views of the mountainous coast of East Greenland. As I (Emma) write we are bashing our way through pack ice off the coast, heading back out into open water after a morning's work. This week Selina Naef, one of two Swiss students here to help with the CTD work, has also contributed to the diary by describing her feelings on her first trip to sea.
How the weather transforms people! Click to enlarge.
Cold, smiling people: Dan, Derek, Kim and Peter.
Warm, smiling people: Peter, Selina, Mindy, Kjetil, Robert and Keith.
The week started with a feat of technical wizardry, as we located, snared and recovered a mooring buoy which even PSO Bob Pickart thought was not recoverable. This success meant the end of mooring work and the start of serious CTD work. The CTD has been working around the clock ever since, gathering data about the East Greenland current as we zigzag across it on our way northwards.
Courtenay takes a water sample. Click to enlarge.
When we are working within the pack ice, the watch-keepers on the bridge have to be extra-vigilant. Not only do they watch for ice encroaching on the ship, but also on the vulnerable CTD wire and the instruments themselves. As we come onto station, a patch of clear water is created by the ship as she turns, so that the CTD can be lowered in relative safety.
George and Derek guide the CTD back on board. Note the area of clear water created to protect the CTD. Click to enlarge.
There have been various other notable events this week, including a sighting of the Northern Lights, the Aurora Borealis, by the 12 to 4 watch-keepers Calum Hunter and Lester Jolly. Aurorae are caused when atomic particles are thrown into space after a sudden flash of energy is released from the sun. They occur near the earth's poles and are therefore rarely seen outside the far northerly or southerly latitudes. During an aurora, "the sky glows with patches of green and red light that can take the form of folded drapery or arches, shimmering and changing shapes for hours on end". The aurora seen by BAS winterers in the Antarctic is called the Aurora Australis or the Southern Lights. Displays at Halley during the winter can be spectacular and may last for many hours.
Science bit in the middle- Mission Improbable.
The mission: to locate a large orange mooring buoy and position the ship within a few metres of it in an ocean with an area of hundreds of thousands of kilometres!
The team: Scott- the brains; Brian and Peter- the brawn; the crew of the JCR- crack buoy recoverers and salty polar sea-dogs; PSO Bob- nervous on-looker.
Bob Pickart, PSO and part time yogi. Click to enlarge.
The story so far:A mooring buoy, deployed in 2200m of water 3 years ago has failed to respond to its signal to release itself from the sea-bed. The buoy carries thousands of dollars worth of scientific equipment and (he hopes) 3 years worth of valuable data for Bob. A small ROV (remotely operated vehicle) and its pilot, Rob Morris, have been seconded to help release the buoy so that it can be recovered.
Final adjustments are made to the ROV by Chris and Rob. Click to enlarge.
The ROV at the surface. Click to enlarge.
First of all, a "happy hooker" was attached to the ROV, and it was despatched to find the buoy. Although the visibility was good, finding the buoy visually was like looking for a needle in a haystack. Enter Captain Elliott and the fish-finder. This, the ship's directional echo-sounder, was able to locate both the buoy and the ROV in the water and guide one towards the other with the aid of some crafty manoeuvering of the ship.
Rob and his "advisors" in ROV mission control. Brian stands in the rain awaiting instruction. Click to enlarge.
The buoy was snared by the happy hooker, a line was attached to its uppermost part and we started to haul in. However, things are never that simple at sea; the line was snagged and the attempt was aborted. The ROV was recovered, the lines reattached and it set off again for another try. And another. And another.
Attempting to pull the ROV and buoy back on board. Click to enlarge.
Success was achieved on the last attempt on day 1: the buoy was hooked and its position marked by a small orange float. We parked next to it overnight and the powers that be devised new and ever more cunning plans.
The new and shiny hook system, complete with (yellow) ballast. Click to enlarge.
Day 2:A new and shinier hook was added to the ROV- the plan was even simpler and this time it was fool-proof. Within a few hours, the buoy was hooked and a large line, capable of taking several tonnes of strain, had been attached to it. Gently the buoy was hauled to the surface and secured on deck. The 3 tonnes of iron anchoring it to the sea-bed was dangling 2 km below us, from our winch. It wasn't until this weight was hauled up to 1000m that it released and dropped back to the sea floor, enabling us to recover the rest of the mooring and Bob to relax.
Success- the buoy (with 3 years growth) is brought on board. Click to enlarge.
A newcomers perspective
by Selina Naef
Day for day goes over on this extraordinary cruise with new experiences in it's fantastic scenery. Huge ice-bergs pass by outside while we move very slowly closer to the coast for CTD station number 63.
Work is going very well, we work 8 hours a day - if we are on a CTD section. Set the carousel, go to the lab and give the OK to the pilot, put stickers on the nutrient bottles, set all other sampling bottles, oxygen, salinity, TIC [total inorganic carbon] and alkalinity for special occasions, watch at the screen to see the interesting profiles, wait till the carousel gets to the previous depth, about 5 to 10 meters above the bottom, then fire all Niskin bottles at different depths and be ready on time for taking the water samples...
If you don't observe the CTD while it 'flies' in the water, you may have some time to go outside and enjoy the amazing scenery around you. You will never have watched enough of this bizarre ice landscape. Today the sea was very quiet and smooth like silk, and in your short breaks on watch you could see the gulls flying over the quiet swells from the sea.
Ice floes off the coast. Click to enlarge.
The coast area here in 65 00 latitude is much flatter then it was where we started with our first CTD section in the very south east of Greenland. The impressive huge glacier which covers the 'whole' landmass of Greenland comes next to the coast, and the big ice chunks may have broken up from this giant glacier. If you wouldn't know that you are at the Irminger sea next to Greenland, you wouldn't believe that this white large cover on the horizon is ice, but you would think there are clouds and fog.
Anyway, it is very interesting to see how the research is going on, to speak to the 'profs' and ask them questions about physical Oceanography and the currents in the Irminger sea at the east coast of Greenland. Actually it is very hard for me to write this text right now in my room, because I can't stay quiet inside while absolutely fantastic ice-bergs pass by, and every five minutes I have to go outside to satisfy my eyes...
During our first week on board we learned about how to TRY to sleep in stormy nights in the open sea, further away from the coast, and how to care about your stuff if you don't want to find it next morning in the garbage beside your table... Fortunately we newbies don't have to be afraid of seasickness anymore, we adapted well and its just a pleasure to stay on this cruise, on this very comfortable ship, with the very friendly and nice crew. And also the scientist are fantastic, and except lab work and water sampling you can do some great things with them as playing tabletable-tennistennis or soccer or just go outside and enjoy it...!!!
This morning we were lucky to experience another wonderful sunrise at 5 o'clock, the colour was very pink. Its to difficult to sleep a lot on this cruise, because you don't want to miss being outside if you see all this amazing views for your fist time and if you know that you will be back at school in a short time...
I know already that I will miss these wonderful moments, the whales and seals we saw, the gulls and fulmars accompanying us everywhere, in storm and fog and wonderful sunny summer weather...
Team Switzerland: Rahel Fent and Selina Naef. Click to enlarge.
Thanks a lot for this cruise. Selina Naef (from Switzerland).
Lest we forget, we are (once again) in an isolated, seldom visited and absolutely beautiful part of the world.
Sunrise over the icy Irminger Sea. Click to enlarge
Many thanks to Peter Koski, Doug Willis and Simon Wright for their photographs.
Next week..... news of the international table tennis tournament (can anyone beat Selina?) and maybe... hopefully.... possibly.... Polar bear sightings???