Ice Diving at McMurdo Sound, Antarctica
Antarctica conjures up images of lots and lots of snow, ice, glaciers, penguins and very little to see, but one thing you would never imagine doing here is Scuba diving. Well, think again! Even though the freezing temperatures that routinely plunge below -40°C (-40°F) and hurricane-force winds have created extreme conditions which have resulted in a land virtually devoid of life. No insects, no plants, no major terrestrial flora or fauna exist here. Yet, life thrives below the thick ice in the icy waters and McMurdo Sound in the Ross Sea has some of the most spectacular diving in the World.
Most of the diving in McMurdo takes place during the summer months of September to February (especially December and January) where temperatures are a more bearable around 30°F (−1 °C). Divers break through the 1.3-3m (4-10ft) thick ice using boring tools like a diesel powered auger, ice saws, ice chippers and even high explosives to make a hole about 1.3 m (4ft) in diameter and a portable hut is placed over this. The hut placed over the hole is mostly to keep the hole from freezing over again and it also provides divers a warm place to suit up. With freezing temperatures and winds outside the portable hut exposed Scuba equipment is at risk of becoming inoperable if not careful.
The water below the thick layers of ice remains a near constant temperature of -1.8° C (28.8° F) and once under, divers can experience an unbelievable visibility of 300m (990 ft)! Once a divers eyes adjust to the one percent of sunlight that makes it through the ice, they describe the experience as flying over a darkened landscape of hills, valleys and sheer cliffs and if one were to look up a spectacular glowing blue cover with a moon like crater that is the ice and hole, is their reward.
McMurdo Sound divers encounter colorful examples of sea life, including bright yellow cactus sponges, green globe sponges, starfish, sea urchin, jellyfish, sea anemone and some brilliant soft coral. One can even spot a Emperor Penguins gracefully swimming to find a meal of squid, fish or crustaceans. Needless to say diving at McMurdo Sound requires a high level of skills and proficiency in drysuit diving.
(*image sources – wikipedia.org, high hat beaver moustache man on flickr)