The OUTPACE 2015 cruise has set sail on February 20! We left port in Nouméa at 8:30 a.m. last Friday morning. I lost sight of land around 10 a.m. or so, and I won’t see it again until we return to port in Papeete, Tahiti on April 3.
Preparations before departure were so hectic that I didn’t even take a moment to appreciate the last time my feet left dry land as I climbed the gangway onto the ship. I spent the majority of my last two days in New Caledonia in a nickel mine north of Nouméa with a man from Vanuatu named Lulu. One of the byproducts of nickel mining is liquid nitrogen, the ultra-cold substance used to make ice cream, slow down the Terminator, and most importantly, preserve our samples until we can analyze them back at our labs on land. There are around 30 scientists on board, and with the exception of the physical oceanographers, everyone needs liquid nitrogen. I am very thankful for Lulu, he was my escort between ship and mine as I filled dewar flask after dewar flask of liquid nitrogen, he was my translator when I thanked the miners for their time, and he very kindly obliged when I suggested that perhaps he could drive slower because the dewars are fragile and his truck had no seat belts.
Having a stockpile of liquid nitrogen is especially critical for the samples I am planning to take during the OUTPACE cruise. I mentioned before that we are interested in how communication between Trichodesmium and other bacteria influences physiology and biogeochemistry. In the Dyhrman Lab at Lamont-Doherty Earth Observatory, we go about answering these questions in part by looking at what genes these microbes turn on or off under different conditions. To do this, we sequence the RNA, or the messenger molecules that act as the intermediary between the genome and the proteins that do the work in an organism. This data provides us with a snapshot in time of every single thing the cell was doing. The unique challenge is that RNA turns over incredibly rapidly. Shortly after fishing a Trichodesmium colony out of the ocean, their RNA profile could change from representing their in situ physiology to representing the response to sudden changes in temperature, light levels or the other stresses that accompany getting jostled around in a pipette by a graduate student trying to maintain balance on a moving boat. From ocean to liquid nitrogen, I have around five minutes before the samples are ruined.
It’ll be a day and a half until I take the first sample of the cruise, however. We’re currently steaming northwest from the southernmost point of New Caledonia to our first sampling station. For now we are rehashing plans, looking at satellite data to figure out where the eddies are and the patterns in sea surface chlorophyll, and finally ensuring every single thing in the lab is secured now that there is the pitch and roll of a cruising ship.