Sunday, January 8, 2012

Southernmost Point

December 16, 2011

LEMAIRE CHANNEL, ANTARCTICA -- Good evening again from Antarctica’s version of an “Inside Passage,” this time specifically at the Lemaire Channel, only about 15-20 miles south of where I wrote from last night, the Neumayer Channel. The reason for this is we began our day by reaching our “furthest south” point, which we officially clocked at 65 degrees, 08.478 minutes south (and 064 degrees, 03.839 minutes west, in case you were curious), accomplished at 9:40am. We were actually intending on heading further south than that, to Petermann Island, but unfortunately about midway through the channel, we encountered heavy ice. We actually tore a good mile or so into the ice, but it got to a point beyond our ability, and given the slow pace, we decided to turn around from there.

While drying off, we had a lecture from Alex, the ship’s geologist, on the subject of ice and icebergs. We covered the coreolis effect, which I first learned about back in AP Environmental Science in High School – thanks Mr. Carlson! The effect basically explains global weather patterns, which come into play down here in Antarctica as well. Since the planet obviously rotates, and the equator is the hottest part of the planet, there is a distinct pattern whereby weather heads in a specific direction and a specific angle, creating points of emphasis at the poles, 30 degrees, 60 degrees, and the equator. This partially explains the Antarctic convergence occurring right at around 60 degrees south. It also explains why the Southern Ocean circulates in a clockwise, west-to-east direction. This is a large part of what makes the Drake Passage so powerful – these unchanging, uninterrupted currents that circle the continent endlessly allow the swells to grow quite powerful, and are what makes the Drake the roughest crossing in the world, and also making the Antarctic convergence the largest biological barrier on earth.

This same effect is what keeps Antarctica so cold – virtually no heat is able to reach the continent, thus keeping it rather covered in permanent ice, which was the actual subject of the lecture. Ice covers over 99 percent of Antarctica, and it is essentially the historical data bank for climate science on our planet. Just recently, scientists were able to drill ice cores giving air samples going back 800,000 years, an increase from the 650,000 year record I previously knew about. Apparently there are ice cores that are known to go back to 1 million years, but getting the confidence interval on their accuracy has been too challenging thus far.

In Antarctica there are basically two types of ice – sea ice and glacial ice. The sea ice freezes on an annual basis, in the winter, and then melts off during the summer. Much of the floating ice around is sea ice. Occasionally, however, we have seen amazingly blue ice, that is actually glacial ice. The glaciers flow out to several ice shelves, such as the Ross Ice Shelf, Ronne Ice Shelf, Amery Ice Shelf, and closest to us, the Larsen Ice Shelf. From there, they eventually break off into the ocean, where they form the majestic blue floating icebergs.

Last note from the lecture – while there is an alarming amount of ice melting in West Antarctica, including the peninsula where we are now, the ice is actually growing in East Antarctica. Regardless, if enough ice melts in West Antarctica, the global impact would be tragically irreversible, which helps to explain the importance of working to combat global warming. If all the ice melted in Antarctica, global sea levels would rise by about 800 feet. Not very likely, but indicative of just how enormous the impact can be.

With our Petermann Island landing impossible, we altered course and set off for Booth Island, somewhere the M/S Expedition had never been before, which is always exciting as an event, bringing a ship into a new place. We had an hour ashore in a driving snow and occasional hail, where we saw a large number of gentoo penguins, blue-eyed shags, as well as the landing site of the most important explorer of the Antarctic Peninsula, Jean-Baptiste Charcot, a Frenchman who was conducting 28 volumes of scientific evidence around 1909.

Despite the fact that we were all thoroughly soaking wet from the precipitation, the wind had died down, and we decided to do a zodiac cruise through the Iceberg Graveyard, an area where glacial icebergs notoriously run aground and thus leave them susceptible to close-proximity exploring. Usually we stay at least as far away from the icebergs as they are tall, in case one flips over (which apparently happens somewhat frequently). When they run aground, however, we can get as close as we want, since that danger is muted. The cruise was phenomenal – it actually stopped snowing, the wind died down, and while very cloudy, the weather was the best we have had in three days down here!

The glaciers were phenomenal – I got a great shot of one reflecting off of still water, and another off of Alison’s (a fellow passenger and Brit on the ship with us) ski goggles reflecting to myself with the ice behind me. I also recorded a lot of video – the still waters made for great moving videos from the zodiacs without fear of water splashing onto the camera. Then, just as we got to our hour and thus time to return to the ship, we got a call over the radio that one of the other zodiacs spotted an orca! We raced off to the sighting, where we saw two beautiful male orcas traversing the bay, surfacing every couple of minutes. Later we found out that one of them actually swam under a zodiac. Perfect ending to another great day in Antarctica!

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