Tuesday, June 17, 2008

OMZ now you know me

Oceanographers are basically professional water filtration junkies. We collect water from different depths in the ocean and then run many batteries of tests to make inferred relationships between microorganisms, physical parameters of the water (Peroxide levels, IronII, Zinc and other important nutrients), and sometimes associated macro organisms. We meet the need to sample certain areas of the water column with a device called the "CTD". The CTD(Conductivity, Temperature and Depth) The device holds a rosette of 24 bottles and these are "loaded or cocked" in the open position before lowering the whole unit in the water. The Bottle are remotely fired from a control station inside the dry lab and everyone involved in the cast decides what area they want to sample. They decide by physical parameters such as florescence and temperature which are relayed real time by the device as it descends. The other reason we leave the bottle open on the way down is they would simply collapse at depth from the pressure. As the rosette makes it's way back to the surface samples are taken based on the log observed as it descended to it's maximum depth. The first 300m of ocean (the euphotic zone-"where light can penetrate") water are generally of the most interest since this is where 99% of all the primary production takes place. Here are some pics of deployment of the CTD from today's station.


The CTd and bottle rosette.Their are 3 accompanying Mexican Scientists on the ship and today was their turn to deploy.

The CTD clears the ship via J-frame winch and is lowered into the Ocean.
Slowly.
As you can see the bottles have openings in the top and bottom to allow water from the sampling to pass through until a desired area is reached and a remote trigger snaps the bottle shut.
You can generally see the CTD for about 75-100 ft since the water is very clear out here.
Once the trip down is made everyone gathers and decides which depths they would like water from. This gathering is somewhat reminiscent of the the NYSE you see on TV.
After the CTD reaches the top temperature tests on each bottle confirm correct firing in the water column. We've had a few problems with 3 of the bottles so they are constantly getting checked.
Besides the two Mexican nationals Jeff and I are greatly outnumbered by the female scientists of the group. These alpha females eat all our food before we can get something to eat sometimes if we don't hurry when meals are served. (kidding) But we do have limited seating so you must eat quickly as to get all the science and crew through.
The reason I was able to stay up and type a post and compile data thus far, was a newly found 15 lb box of gummy bears in the snacking area of the galley. The sugar rush is about to crash however.
Over the next 24 hours we will be sampling 3 stations so until then I may not post. If you have any requests fro pictures of different areas of the boat send them my way. Otherwise I will just try to make an effort to represent the ship and operations as a whole. Until next time....

3 comments:

Dave Holmes said...

What about the supposed "floating pile of plastic bottles the size of texas" somewhere in the pacific? I want pictures of that...

elizabeth said...

OMG - I don't check the internet for a few days and look what I missed!

I like pictures, so yeah if you want to send some my way, my email is
ryanmac1027 at gmail.

Have fun on your "cruise"

Unknown said...

Haven't you decorated your cabin yet? Get any stowaways this time?

=D=