The idea of this cruise is to repeat P6, a transect last measured in 2003. We are moving East along the 32° 30” parallel, dropping a CTD in the water every 30 nautical miles. CTD stands for Conductivity (read: salinity), Temperature, and Depth, the three most important values it measures. My job is to control this $1 million plus instrument as it travels to the sea floor and back up.
Because of the collaboration between so many institutions in this project (including Scripps, WHOI and UW, my three top choice grad schools), there are various other instruments attached; flourometer measures bio-content, ADCP measures minute current iterations, O2 measures O2, and a transmisometer (spelling) measures the Chromophoric Dissolved Organic Matter (biology related, I think).
Also on this huge package we drop in the water are 36 Niskin Bottles, which are rigged to “trip” and collect water when I press a button. We trap water from various depths, bring it to the surface, and various groups will sample it for different quantities or values; to give you a list, Freon, Helium, Oxygen, Dissolved Inorganic Carbon, Dissolved Organic Carbon, various Carbon Isotopes, Tritium, Nutrients, Alkalinity, Bacteria, PH, CDOM, POC, and D15. Once the package is up, I get to play “sample cop” where I control who samples from what bottle, a power which quickly went to my head.
To sum up, we are traveling across the Pacific at about 12 mph, stopping every three hours for a four hour cast. We’re on day 19 of about 38 days, half way there.
Things I learned:
--How to sample from Niskin Bottles.
--The world’s tritium supply was created as we were conducting nuclear weapons testing, and is used to this day to follow water types, a proxy for sediment dating, among other things.
--Radio etiquette (i.e. “Roger”, “Over and Out”, “Breaker Breaker, one…nine”, etc.)