Drake Passage
Today is a day at sea as we head north through the Drake Passage. This morning we are still in Antarctic waters both politically and biologically. We are still south of 60 degrees south latitude, a political boundary for the Antarctic Treaty System. I do not usually find treaties too exciting, although there have been great benefits from these. Nonetheless, I’m more interested in biological boundaries, in this case the Southern Polar Front and the Antarctic Convergence.
There is a protective boundary around Antarctica. You can feel it in the air, the Southern Polar Front, you can feel it in the water, the Antarctic Convergence. When traveling north to south, in a period of several hours it becomes noticeably colder, perhaps 10°F colder! That is a lot when the temperature is near 32°F. This fairly much separates the Antarctic marine environment from that of the rest of the world. For this reason, the area south of 60° south latitude is often called the Southern Ocean. However, this is not an official name. Indeed, according to the National Geographic website, the Antarctic continent is only touched by the Atlantic, Indian, and Pacific Oceans, there is no Southern Ocean. Part of the problem is that both the Antarctic Convergence and the Southern Polar Front move about, quite the problem for geographers, but not to me, I’m a biologist.
As the day continues, with light winds and moderate seas, there are clouds broken by patches of blue. The air is getting warmer and the water is becoming more blue, less white. Up ahead there seems to be a line of fog, marking the northern edge of the Southern Ocean? I think so and so too do most of the animals and algae. So, “Here is to good treaties, good friends, fellow travellers and the eccentricities of Nature!”