Saturday, 6 April 2013

Day 23: Science in the real world

Hello again blogwatchers,

As promised, here is part two of the sorry tale of scientific planning’s contact with the real word.  

In the unlikely event that you could trap them in a social situation and ask, most scientists will claim that studying the real world is what fascinates them, drives them to get up in the late morning and inspires them to write dust dry multipage treatises where the word ‘rigorous’ is used a lot.  In actual fact, the real world is troubling for most of us scientists.  Unlike the theory of what we study, the world in which we live is messy, constantly changing, difficult to observe and sometimes disturbingly sticky. For geoscientists like oceanographers, there is also a very frustrating lack of spare planet Earths upon which to run proper control experiments.  

So when groups of scientists gather at conferences in whichever exotic location has the best skiing/surfing at that time of year, the neat Southern Ocean experiments that they plan begin to look like less good ideas when, two years later, those same scientists have to go to the captain and politely ask for his expensive and recently painted ship to head into thick sea ice.  At night.  With the barometer plumbing new and exciting depths.

That was the latest trial of the terminally optimistic VL Jean-Baptiste who, having vanquished the fog and winds plaguing the VMP by the traditional French tactic of waiting until it got bored and went away,  faced his next task of picking up and redeploying moorings from the ocean floor.  This can be somewhat tense work at the best of times as you must first find the mooring location, send the secret handshake that causes the mooring to float upwards, locate the bobbing bits in the sea and then try to retrieve them all without tangling the hundreds of meters of cable in the ship’s propellers.  Fortunately, the crew of the JCR are old hands at this sort of thing, but the sight of the masses of unseasonal sea ice that greeted us at the mooring location still caused a few subconscious tugs on safety harnesses.  


Pictures:  Left, the science plan, dots are the moorings.  Above, in practice.  The red squiggle ending in the middle of the green circle is the ship track.

After a tense night of sailing up and down the line of six moorings, stretched across about 20 miles of the fun-to-say Orkney Passage, a gap in the ice big enough for a retrieval was located.  At first light Paul, Phil and James, masters of the moorings, immediately leapt into action and sent the release signal.  Right on cue the mooring bounced to the surface like a puppy left at home alone all day (or over a year in this case) and was promptly hauled in.  A rapid turnaround was in order as the ice was thickening and the forecast for the rest of the week was grim.  The mooring was quickly downloaded, recharged and put back in, but as the amount of ice free sea rapidly shrank, a problem became clear.  Normally a mooring, which is actually a string of floats and instruments up to 2km long with a big weight on the bottom, is deployed top (float) end first.  The ship then slowly moves forward paying out the rest of the mooring as it goes, with the weight only going in last and dragging the rest down with it.  This requires a bit of sea room however, and with the wind rising and house sized chunks of ice grumbling past, leaving two km of trailing wire and floats behind the ship seemed less wise.  

 Picture:  Leadership in action.  JB supervising the deployment of a mooring from the warm control room. 

Several physicists onboard immediately proclaimed the problem solved, and therefore uninteresting, and asked why we simply didn’t deploy the weight first?  Rather than trailing behind the ship the mooring would hang down and avoid any glacial tangles.  With the patience of someone explaining compound interest to a kitten, the deck engineer politely described how in the real world things like ‘winch loading, ‘cable tension’ and ‘coating abrasion’ cannot simply be approximated as zero.  With the prospect of possibly only getting this single mooring done, JB vented his frustration on the vacationing CTD team and ordered them to their stations.  Science at all costs, and if he couldn’t have moorings, he’d have CTDs damn it.  Cursing the resilience of our instrument, the CTD team labored through the night.

Dawn broke and the mood was temporarily lifted by the appearance of a whale which circled the ship only a few meters off as scientists and crew alike rushed from side to side waving more cameras than at an Oscar’s reception.  Even grizzled veteran of more than 30 years at sea, George, who could only be more worthy of the title ‘old sea dog’ with a peg leg, was following it up and down the side of the ship with glee.  He later denied this, and when asked what type of whale it was he gruffly declared it ‘twer just a bloudy big black one. T'with white bits’.  I think the smile gave it away though. 

Picture: Definitely big.  And black.  Don’t argue with George.  

Despite the increasing winds the mood of all aboard was lifted further when Paul and the deck crew declared that they had come up with a solution to the weight first dilemma.  Intensely practical engineers and experienced hands, they had arrived at a solution without a single equation, and therefore it was far more likely to succeed.  The plan was thus: Rather than dangling the whole of the mooring, instruments, weights and all off the winch, it would be possible to lower the weight into the water first.  That could be lashed to the deck fixings so the winch wasn’t taking the weight, then one by one the instruments could be deployed, repeating the lashing to free up the winch, and finally once all was in, let loose.  

In practice this produced a nightmarish criss-crossing of ropes and cables on the rear deck, a veritable cat’s cradle of lashings, knots, pulleys and turns around bollards.  It seemed one wrong tug on a rope would cause the whole lot to spontaneously deconstruct and drag everyone on the deck into the deep, and probably the ship with it.  But, like a midget at a urinal, the moorings team and deck crew were on their toes, and had the whole situation under control.  Five days of near round the clock work on the deck and in the lab, and the last mooring was redeployed.  The manly men of the aft deck, closely bonded now after working every grease stained day in freezing temperatures and high winds, celebrated with one, two, three pats on each other’s backs.  This outpouring of emotion was declared ‘very sweet’ by Gwen, who was watching the show unfold from the warmth of the instrument room. 

Picture:  A mooring weight being deployed.  Somewhere a train is up on bricks.

So, science achieved, despite the real world’s best efforts, the JCR steamed on towards our next goal, the A23 line of CTDs.  Stay tuned dear reader. 

1 comment:

  1. "like a midget at a urinal" I love this. I'm going to have to steal it. Thanks for the awesome updates from both of you. Its great to find out a bit of what goes on on those southern ocean science cruises.