Ambling Sampling: December 2012

NOAA (National Oceanic and Atmospheric Association) is the government agency who controls information regarding to the current or future weather conditions. For the last three weeks, we used the NOAA Ship Pisces for the recovery and deployment of several oceanographic moorings in the Tropical North Atlantic.

(Link for our CRUISE TRACK; select ship PC, last 30 days.)

“We” in this case includes researchers from SIO and WHOI, the two leading oceanographic facilities in the world. WHOI did the majority of the work, and therefore sent more researchers. SIO had only two goals related to our MOVE project, and sent only me. NOAA provided the ship personnel, including NOAA officers (drive the boat), engineers (keep the boat running), cooks, and deckworkers.

Some background: The Meridional Overturning Circulation (MOC) consists of the Gulf Stream (transporting warm water north along the Eastern Seaboard of the USA) and the deep water return flow (transporting cold water south along the bottom of the Atlantic Ocean). Some researchers say that Climate Change predicts the MOC to slow down with dire consequences; The Day After Tomorrow is based on this idea. It is important, therefore, to monitor the MOC, which is the purpose of my lab's MOVE project.

Sunny recovery

Basically, I was on a boat to save (or at least warn) Jake Gyllenhaal in The Day After Tomorrow.

--Primary goal: Recover a single bottom-mounted instrument.

--Secondary goal: Establish acoustic communication with 4 other instruments.

Recovery was successful; I sent an acoustic signal to the instrument, releasing it from the seafloor. It floated to the surface and we spent a long time looking for it (beachball in an ocean). Once we brought it on board, I downloaded it's four years of data and made triple-backups.

Acoustic download is an interesting process, related to the old dialup connections. Those connections would use sound over the phone line to transmit information; AOL's “ooooo-uuuu-eeeeee-aa-oooo-aa-ooooo-uuuu-eeee-oooo” described the phoneline's 56K modem (i.e. 56,000 bits/sec). With the acoustic communication, I used a similar method (and it even sounded similar), though only at 140 to 800 bits/sec. This snail pace was enough at one location, and I downloaded a near-complete set of data. At other locations, I was only able to “ping” the instrument, making sure it still existed.

Sunrise after a night of Acoustic Comms

WHOI was on the vessel to recover their old full-depth mooring, and deploy a new one. I have taken part in several such deployment/recovery efforts (see POST), so I helped them as well. The float for their mooring actually broke free, so we needed to chase it down near South America.

Schedule:

Day 1-6: Full ahead steam.

Day 7: Deploy WHOI Buoy

Day 8: Partial WHOI Recovery. Acoustic Communications.

Day 9-10: Catch up to WHOI Float

Day 11: Recover WHOI Float

Day 12-13: Steam to Acoustic Sites

Day 14: Partial acoustic download. Acoustic Communications.

Day 15: St. Croix!

Day 16-20: Fuller ahead steam (you always travel faster BACK to port)

Somethings interesting:

--There was one day where the ocean was bone-glassy. There were 3-4 days where the ocean was a punishing 10-12 foot, with 40 knot winds.

--St. Croix was really neat, though I was only able to taxi to a beach and hang out. To get back to the boat, I had to trade my straw hat for a ride; we had spent our money on food, etc.

--If I wait until the end of a cruise like this, it gets too long (e.g. description, background, anecdotes). I'll try to post during the cruise in the future.