FROM THE FIELD
Ocean of Extremes
New York City to Punta Arenas: The Beginning of Our Journey
What brings 33 climate scientists and (paleo)oceanographers from 13 different countries to the end of the world in Punta Arenas, Chile, in the middle of Southern hemisphere winter? It is a very special ship, docked at the pier in Punta Arenas: the R/V Joides Resolution, a unique research vessel that can drill thousands of feet into the ocean floor to collect sediments. Not only does the Joides Resolution have a 180-foot-high derrick for its drilling operations — it is also a floating laboratory with state-of-the-art facilities for micropaleontology, sedimentology, paleomagnetic, physical and geochemical analyses.
I am one of the two co-chief scientists leading a two-month expedition to the Pacific Sector of the Southern Ocean. I’m joined by two Lamont-Doherty Earth Observatory post docs, Julia Gottschalk and Jenny Middleton. Expedition 383, aka DYNAPACC (Dynamics of the Antarctic Circumpolar Current), has been in the works for almost a decade, from the initial idea and site survey cruise, through countless conferences to this moment in Punta Arenas. My co-chief Frank Lamy from Alfred Wegner Institute, Germany, and I have spent much of the past year planning every detail of this expedition, most importantly putting together the team of 33 scientists from a total of 13 countries. I was the last of the team to make it to Punta Arenas — due to flight cancellations and delays in Houston and Santiago it took me more than 50 hours to get from New York City to Punta Arenas, at the southernmost tip of South America — and it feels great to finally meet all the science team and the crew with whom I will spend the next two months.
After a couple of days at the dock bunkering food, supplies and fuel, we sailed through the breathtakingly beautiful Strait of Magellan (which you can see in the video below) on a sunny and not too cold winter day, and then on to the Pacific Ocean. The R/V Joides Resolution is more than 400 feet long, and we have 123 people on board: 33 scientists, 26 support staff members from the International Ocean Discovery Program and 64 crew members.
Why are we doing research in the Southern Ocean? The Southern Ocean plays a powerful role in Earth’s climate. It stores more anthropogenic heat and carbon dioxide than any other latitude band on Earth. We know that the Southern Ocean is changing rapidly as the world’s climate warms, yet we lack the basic understanding of the processes controlling this important element in the global climate puzzle. A major goal of our expedition is therefore to collect data to improve our understanding of the Southern Ocean’s climate engine and its variability today, in the past and, perhaps most importantly, in the future.
A major feature of the Southern Ocean is the Antarctic Circumpolar Current: arguably the most important ocean current on the planet. As it encircles the Antarctic continent, it is the world’s strongest ocean current system (it carries more than 150 times more water than all the world’s rivers combined), connecting all three major basins of the global ocean (Atlantic, Pacific, and Indian) and isolating the enormous Antarctic ice sheets and keeping them frozen.
The Southern Ocean also is one of the most remote regions of our planet, and hence it is not surprising that, in spite of its global importance, we do not know a whole lot about this region. To fill this gaping hole, we hope to drill 21 holes, up to 1500 feet deep into the seafloor, at seven locations. Marine sediments accumulate bit by bit, like a layer cake, with the oldest sediment at the bottom and the youngest on top, and record climate variability like a tape recorder. The sediments gathered from the ocean floor will allow us to study how Southern Ocean winds and ocean currents have responded to past climatic changes and how the ocean, atmosphere and Antarctic ice sheets may respond to future warming. A better understanding of the natural variability of this region in the past and its sensitivities will help us to predict the Southern Ocean’s role in a warming world, and it will help us to better predict the future of the Antarctic ice sheets and their potential contribution to global sea level rise.