All about Antarctica

Throughout this podcast, we have traced the history of Antarctica from its geologic origins, its earliest discovery and the first people to set foot there, to the first research stations and into the modern world. Even though Antarctica has been impacted throughout the past 120 years from research stations, tourism, and external anthropogenic factors such as climate change and pollution, it still remains the most remote and pristine place on earth, an extreme environment so relatively few people visit it. In this final episode, I go over the greatest threats facing Antarctica today, including global warming and sea level rise, and the importance in maintaining the Antarctic Treaty and Antarctica as a world park. It is up to all of us to ensure that Antarctica remains for peaceful purposes only. 

Although Antarctica is still the most remote and pristine place on earth, there have been many human-caused impacts to this continent and the marine environment around it. These impacts include pollution from research stations, tourism, and introduced species.  In this podcast, I discuss these impacts and how they led to the Environmental Protocol in the Antarctic Treaty in 1991. In addition, I give the history of tourism and when the first women are known to have visited the frozen continent.  Tourism (ship and air), which has been increasing exponentially since the 1970s, is now controlled by the tourist agencies themselves when the International Association of Antarctic Tour Operators (IAATO) was formed in 1991 to promote safe and environmentally responsible travel to Antarctica. Introduced species still arrive in Antarctica either naturally or from researchers and tourists, but most of these exotic species fail to survive there. I discuss a few of these species that have managed to gain a foothold in Antarctica today, facilitated in part of global warming trends that provide a more suitable habitat for them. 

After the International Geophysical Year of 1957-1958, Antarctica became a focus of scientific research that continues to this day. In 1958, most of Antarctica was under territorial claims by seven nations, with overlapping claims between Britain, Chile, and Argentina leading to conflicts.  The U.S. President at the time, Dwight D. Eisenhower, called for claimant nations to hold a series of meetings and work out an agreement so that Antarctica could remain for 'peaceful purposes only'. These meetings led to the Antarctic Treaty of 1959, one of the most successful international treaties every signed. In this podcast I describe events leading up to this treaty and how it helped resolve international disputes. I also describe my own research on why Eisenhower never made a territorial claim for the U.S. in Antarctica, despite pressure at home to do so. 

As we enter the heart of the Heroic Age in Antarctica, three men become competitors to be the first person to reach the South Pole: Robert Falcon Scott, Ernest Shackleton, and Roald Amundsen.  Scott and Shackleton had a falling out after Scott's Discovery expedition when he blamed Shackleton's illness with scurvy as why they didn't reach the pole at that time.  Here I give the history of Shackleton's attempt to reach the pole during his Nimrod expedition in 1907 and when he began emerging as one of the greatest leaders in British history.  Then, Scott tries again in his Terra Nova expedition of 1910-1913 but, just after departing England he learns that the Norwegian, Roald Amundsen, was also heading south to try for the pole. The race was on and the events leading up to it, its tragic outcome and mistakes made are described in this podcast. 

When the topic of penguins is raised, most people tend to think only about Antarctica as their habitat. However, of the 19 living species only five actually occur in Antarctica and of those, only two are endemic there. In this episode I describe the breeding cycle and adaptations of these species to the cold Antarctic environment. The cold, dry conditions also preserve tissues in ancient deposits which is the subject of my own research in Antarctica. Some of these tissues date as old as 45,000 or more years, but look and feel modern. Other seabirds reviewed here include the endemic snow petrel and my favorite, the south polar skua.

Although only about 2% of Antarctica is exposed as ice-free land, there are hundreds of lakes found there that vary from freshwater to saline.  There are even hundreds more that are below the ice sheets that have been hidden and isolated there for millions of years.  In this episode, I review the different types of lakes found in Antarctica and the life within them. These lakes include the most saline lake on earth, Don Juan Pond which is 18x saltier than the ocean, and the most isolated lake in the world, Lake Vostok, a large freshwater lake that is 4 km below the ice sheet on the polar plateau. 

In Part IV of this podcast, I described how sea ice forms and traps marine algae that can grow in the ice before it’s released back into the ocean when the ice melts. This process drives marine productivity in Antarctica starting with krill, a small crustacean that is a keystone species there. In this episode, the life cycle of krill is described and why it is so important in the marine food web. The rich diversity of benthic invertebrates also is presented and the current threat to this community by the invasion of king crabs from South America. A unique group of ice fish also is described and how these species evolved in isolation in Antarctica in waters at less than 5 degrees C.  These fish can withstand freezing temperatures and some absorb oxygen from the water directly through their skin. 

Sea ice is a major feature of Antarctica and has considerable influence on ocean currents and marine ecology. In this episode I describe how sea ice forms and traps marine algae that stimulates the marine food web when the ice melts.  Thus, sea ice provides a direct link between the physical and biological worlds that is important for marine productivity all the way up the food chain to penguins, seals, and whales.  Sea ice extent varies each year in Antarctica and also is an important driver for ocean currents and mixing.  Polynyas are highly productive areas of open water surrounded by sea ice and are formed by katabatic winds or warm water upwelling. They determine the colony locations for most Adelie penguins as they are important foraging grounds for this species. 

In this episode, I describe the geologic origins of the Antarctic continent and how it changed and developed over millions of years to become the coldest and windiest place on earth that it is today. The concepts of plate tectonics and continental drift are presented and play a key role in shaping the continent and in understanding its rich fossil record that includes ancient forests, dinosaurs, and giant penguins.