A scientist reports from Antarcticaby Rich Viso
Editor's note: Coastal Carolina University scientists Rich Viso and Rick Peterson, accompanied by graduate student Leigha Peterson (no relation,) embarked on an oceanographic research cruise in the Antarctica in early December. While Viso and Peterson have returned, Leigha Peterson remained to conduct more technical tests on groundwater discharge and will return in mid-February. The following is Viso's account of the highlights of the trip.
The most common questions I have been asked about travel to Antarctica center on the temperature, the landscape and the course of events that led us to travel there.
A hypothetical direct flight from Myrtle Beach to Palmer Station on the Western Antarctic Peninsula would be just over 7,000 miles. Our flight route was from Myrtle Beach through Atlanta to Santiago and then to Punta Arenas. From there, we boarded the Antarctic Research Support Vessel Lawrence M. Gould and made the 600-mile journey through the Strait of Magellan and across the Drake Passage to Antarctica.
The Gould is equipped to spend more than two months at sea at a time and has a reinforced hull that can break one-foot thick first-year ice while continuing to make forward progress. It was summer in Antarctica, and while we and did not have to break ice, but we did bump through a fair amount of broken ice at times.
We were exceptionally lucky in our travel with only minor obstacles along the way. The Drake Passage is notorious for some of the roughest seas in the world. The Gould makes several crossings a year between South America and Antarctica. During our trips down and back, the crew of the ship commented often that we had the best weather they had ever experienced. The maximum seas were probably in the 6-8 foot range, a far cry from the 30-50 foot waves many have experienced in the same area.
It takes approximately four days to travel by sea from South America to Antarctica, and we took advantage of the good weather to set up the labs on the ship and practice our sampling and analysis routines. The chief scientist for this project is Reide Corbett from East Carolina University. He secured funds through the National Science Foundation to undertake sampling of sea water on the continental shelf of the Western Antarctic Peninsula. The samples are then analyzed for naturally occurring chemical tracers that give clues to the origins of the water. How much fresh water is flowing from Antarctica into the ocean water? How much comes from melting glaciers? How much of the fresh water is groundwater? How does this water mix with the ambient ocean water?
Another important analysis includes an attempt to quantify the amount of iron in these water sources. In the Southern Ocean, iron is a limiting nutrient. This means that the base of the food web is controlled to a large extent by the presence of iron. Many sources for iron in this area have been considered, including glaciers and atmospheric sources (dust). The amount of iron contributed by benthic sources is, at best, poorly constrained. Our mission, under the guidance of Corbett, was to make progress on understanding this system.
The project had two components. The first was the research cruise on the Gould. Due to good weather and hard work, we finished this objective and actually acquired a large amount of additional data, beyond the original scope of work. The second phase involved more spatially and temporally intense sampling in the nearshore area of Antarctica. Corbett and three graduate students remain at Palmer Station until mid-February to collect samples. One of these students is Leigha Peterson from CCU's graduate program. More on her experience will follow in the next couple of months.
We are very fortunate to have made this journey. The landscape is far from bleak, with huge jagged mountains actively being shaped by the immense thickness of ice flowing through them. The scenery is beautiful, but definitely lends the feeling of the awesome and sometimes forbidding power of nature. The United States Antarctic Program made sure we were properly outfitted to complete our work in this extreme environment, and such support is absolutely necessary to survive. We were well equipped to sample large volumes of seawater (more than 50,000 liters so far) and be comfortable while doing so. It is a real privilege to be conducting such work in such a beautiful setting. There was 24-hour daylight, and even while working overnight, one can take the time to pause and marvel at the vast spectrum of changing colors in the ocean, land and icebergs all around.
Near land we saw penguin colonies, elephant seals, humpback whales and many different birds. The temperature was near freezing, but not uncomfortable due to the calm winds. Upon finishing our work at sea, we stopped at Palmer Station to drop off the scientists who are still completing the sampling. We spent a night there, which afforded us the opportunity to hike up a glacier as the sun went down. (The sun goes down, but there is still daylight, twilight, etc. It never gets dark. There are about 19 hours with the sun up and about 5 hours of twilight.) After the hike, discussions turned to how it must feel to plunge into the icy waters of the Southern Ocean. A few minutes later, we all stripped down to swim attire and jumped in. We literally had to push aside chunks of sea ice to get back out and then run through the freezing air to a hot tub while experiencing the worst “ice cream headaches” one can imagine.