Wednesday, January 14, 2009

oxygen pt 2 and PENGUINS!!!

Well I know you're itching to hear more about dissolved oxygen and
what it means to me. Because DO content reflects where the water has
been and what's happened to it, we can learn about the circulation
from it -- especially when we have complementary "tracers" which tell
the same story, or can differentiate processes which may lead to the
same effect on DO. We're particularly interesting in the flow of
"old", subsurface water, its access to ice shelves, and the flow of
meltwater away from these ice shelves. In this context, "old" means
it's been a long time since the water has been at the surface, where
it can equilibrate with the atmosphere (for those interested, its DO
content is ~4mL/L). Over time, biological detritus (poop) sinks and
microorganisms eat it, using oxygen in the water in the process.
This deep water is upwelled (rises) when it gets into contact with
ice and freshwater mixes with it. Since the DO content is lower in
the old water/ice shelf water mix than it water that's recently been
at the surface (~8mL/L), we can identify it, even if it is the same
density, salinity, or temperature as the water around it.

Penguins are becoming more frequent as we move south through the ice.
Though I've heard one report of an isolated emperor, all I've seen so
far are adelies -- which are my favorite anyway. I was fortunate to
get off the ship and get lowered onto the sea ice to help out with
some ice coring and related analysis (see pictures on my web site if
you're interested in seeing how this works...). It was a brilliant
day -- bright and right about freezing. We had two Adelies pay a
visit almost immediately, and they hung out with the two groups of
people that were coring two different areas on the ice floe. One was
extremely interested in our ice corer and was almost sticking his
head inside. We tried to act serious but it's very hard with
penguins watching.

Oh, and land ho! Thurston Island is visible to our East as we near
Pine Island Bay.

2:30 am and still titrating oxygen, I remain,


  1. OMG I can just picture it with the penguins. I'm dying! How adorable. Wish I could see a pic.

    Why is it that penguins are just inherently funny?

  2. How does churning from berg movement and storms work with DO levels?