Pop quiz: How many oceans are there on the planet?
Answer: It depends on whom you ask—but as of June 2021, most official organizations would say there are five oceans.
The Atlantic, Pacific, Indian, and Arctic Oceans are all long-established fixtures in cartography, but there’s been some international debate over what some refer to as the Southern Ocean, the body of water that surrounds Antarctica. If you’ve heard of the Southern Ocean, it’s because scientific bodies like the U.S. federal National Oceanic and Atmospheric Association (NOAA) have for decades recognized it as a separate and distinct body of water, yet it’s still not recognized by the International Hydrographic Organization (IHO) due to a lack of consensus among member countries. In years past, the Southern Ocean was frequently left off of world maps, or when it did appear, it came with a qualification.
But the Southern Ocean’s status is experiencing a sea change, following the National Geographic Society’s announcement on World Oceans Day in June that it would now recognize the body of water on its widely used maps, a move that intends to bring more attention—and conservation muscle—to the area’s fragile ecosystem, and perhaps even pave the way for the IHO to recognize it, too. This new designation bodes well for both science and conservation, according to Dr. Verena Meraldi, a biologist and chief scientist of Hurtigruten, a Norway-based cruise company whose offerings include expeditions into Antarctica.
“Recognizing the Southern Ocean as an independent entity, and understanding the role it plays in global circulation, is one huge step towards the increased development of scientific research projects and conservation of all species that call this ocean home,” Meraldi says.
The Southern Ocean ecosystem is unique for several reasons. First, the ocean is divided by a current rather than a continent, called the Antarctic Circumpolar Current (ACC), the planet’s strongest current. It also connects the Atlantic, Pacific, and Indian Oceans, allowing for the crucial interocean exchange of carbon dioxide, heat, and other chemicals that help to regulate each body of water. And when the ACC is squeezed through the Drake Passage, a portion of the Southern Ocean’s cold waters flows north as far as the equator and Galápagos islands, and they play a crucial role in balancing out the environments of these faraway habitats.
In addition, the Southern Ocean is one of the most productive feeding grounds in the world: During winter, 50 percent of the ocean is covered with ice, and when that ice thaws in the spring, it creates a unique surface layer of less salty water that causes phytoplankton to thrive in so much abundance that it resembles a milky substance that can be seen from space.
“Phytoplankton are microscopic plant-like organisms that are not only the base of every food web in the ocean, but they also produce half of the oxygen we breathe,” Meraldi says. “This extremely abundant explosion of life attracts many other organisms to the Southern Ocean.”
Wildlife that depend on phytoplankton include such iconic polar species as penguins, especially during their breeding season and annual molting, while whales depend on the krill that feed on the phytoplankton as they replenish their fat reserves before returning to their breeding grounds.
Thanks to the remoteness of the Southern Ocean and the need for scientific study, tourism and science often cross paths in Antarctica. According to Meraldi, cruise companies like Hurtigruten, which began operating in Antarctica in 2002, have witnessed environmental changes in the region—including penguin population numbers and higher recorded temperatures—and these observations have led to increased collaborations with scientists with each passing year.
Today, it’s common to see researchers working aboard tourism cruises, where they often share their findings with guests. It’s not unheard of for guests to be privy to groundbreaking discoveries: Meraldi cites a 2019 Antarctica trip in partnership with the Norwegian Polar Institute where a Hurtigruten vessel brought supplies to scientists in the Shetland Islands, and picked them and their equipment up at the end of their months-long stint in the region.
“They presented their preliminary results to our guests and staff during the trip to Ushuaia,” Meraldi recalls, referring to the capital of Tierra del Fuego, Argentina, and the country’s southernmost city. “They were the first to hear about the striking differences in foraging patterns during the breeding phases of the chinstrap penguins that this study revealed.”
How to visit the Southern Ocean
Ready to nerd out in the world’s newest ocean? Read on for four cruise companies that visit the Southern Ocean, with a heavy emphasis on guest education, and are striving to lighten their environmental impact, too.
Cruises to the Southern Ocean with Hurtigruten range from 12 to 23 days, and on-board Science Center programming for guests includes hands-on citizen science programs, which vary by region but might include surveying penguin populations or collecting data on leopard seals. On the 500-passenger MS Roald Amundsen, which launched in 2019 as the world’s first hybrid electric-powered expedition ship, the Antarctica, Chilean Fjords, and Falklands—Great Explorers and Solar Eclipse is an 18-day journey. The next sailing takes place in November 2021 and includes an astronomer-guided viewing of the solar eclipse from the South Orkney Islands.
The company’s new 75-passenger, ice-class Magellan Explorer was designed to lower its environmental footprint by recycling the water supply aboard it, as well as engine heat, which is used to warm the ship. The two main engines comply with the most stringent shipping industry emission standards, and the vessel produces its own fresh water through an onsite desalination plant and can compact and store all waste onboard. Itineraries into the Southern Ocean aboard the Magellan Explorer include the Falklands, South Georgia & Antarctica Sea Voyage, a 19-day expedition departing in September 2022 where rockhopper penguins, black browed albatrosses, king penguins, and elephant seals are common sightings.
Lindblad’s new 126-passenger National Geographic Endurance ice-class expedition ship has a Science Center that serves as a hub for resident science teams—it’s the site of research and presentations of their projects to staff and guests, including footage from underwater and drone cameras. Departures include the 35-day Epic Antarctica: From the Peninsula to the Ross Sea & Beyond in December 2021 that will take travelers into remote parts of west Antarctica and explore the rarely seen sub-Antarctic, wildlife-rich islands off of New Zealand and Australia.
Science and conservation education remain a central focus of the guest experience on Quark Expeditions’ Antarctic cruises. Guests rub shoulders with glaciologists and marine biologists, who can offer context on wildlife and melting ice as guests experience them. The new, 199-passenger Ultramarine vessel has two helicopters that are quieter and more fuel-efficient, and the ship’s Micro Auto Gasification System (MAGS) turns waste into energy onsite. The 16-day South Georgia and Antarctica Peninsula: Penguin Safari itinerary sails in November 2021 and February and March 2022, and focuses on sightings of the king, chinstrap, and Adélie penguins among other polar wildlife encounters.