Monday, March 14, 2016

Curiosity Challenge: Weather and Animals in Antarctica

"What's the weather like in Antarctica?" -- Aaliyah Bester, 7

"How do animals survive in the Antarctic?" -- Josephine Sawyer, 8
My friend Rachel stands on the bottom of the world
with the Geographic South Pole marker!
Courtesy of Rachel Bowens-Rubin.
The Antarctic is a really “cool” place--both because of how neat it is, and because it’s so cold!  In fact, the coldest temperature ever recorded on Earth was −89.4 °C (−128.9 °F), at the Vostok Station in Antarctica.  I’ve been hearing a lot about Antarctica lately because my friend Rachel has just returned from a trip to the South Pole, which is right in the middle of the continent.  Rachel is an astrophysicist, which means that she studies the physics of stars and planets by looking at them through a telescope.  She was using a telescope at the South Pole to search for special waves in space that might tell us more about how the universe was formed, as part of the awesome BICEP3 experiment.

Rachel helped build this part of the
BICEP telescope, then fly it to Antarctica.
Notice the heavy cold weather gear she had to wear,
 even while working.  Courtesy of Rachel Bowens-Rubin.
 
Why did she have to go all the way to the bottom of the globe to use a telescope?  The answer has to do with Antarctica’s crazy weather.  
Believe it or not, Antarctica is actually a desert.  It isn’t hot and sandy, like how we usually picture a desert, but it has very little rainfall.  It stays so cold that no clouds can form, because any water droplets that might be in the sky freeze right away and fall as snow.  (None of this snow ever melts, so there’s snow and ice in Antarctica that has been around for thousands of years!  Studying this ice can tell us really interesting things about what the Earth was like back then.)  The lack of water droplets means that the sky is very clear, making it the best place on Earth for Rachel and her fellow scientists to use their telescopes and do their experiments!

What's a day like in Antarctica?


A diagram of the Earth's tilt, which causes the 6-month
 seasons at the South Pole.
Via Pinterest.com
Scientists working on the South Pole Telescope,
which is 10 meters (30 feet) long!
Courtesy of Rachel Bowens-Rubin
One of the strangest parts about living at the South Pole is that there’s only one full day a year: the sun shines for about five months (the austral summer), there’s about three weeks of sunset, and then it’s dark out for five months straight (the austral winter).  This weird schedule has to do with the constant tilt of the Earth as it revolves around the sun over the course of the year.  For one half of the revolution, the South Pole is pointed at the sun, and for the other half, the South Pole is pointed away.  Can you imagine going to bed when it’s still light out, or not seeing the sun for six months?

Of course, having no sun in the winter also means it’s much, much colder.  The scientists who venture outside in the winter cover every inch of their skin with thick clothing, and they only stay out for a couple minutes.  Even in the summer, Rachel had to wear a heavy coat and goggles outside.  Since Antarctica is a solid ice sheet with no trees or rocks, wind can move very quickly across the surface, causing the most extreme weather in the world.

Antarctic Animals

There are no animals living at the South Pole, besides human scientists and some very hearty bacteria.  Out towards the shore and on Antarctica’s many islands and ice floes, the weather is not as extreme, so penguins, seals, migratory birds, and whales can find fish to eat and warmer temperatures to live in.  Even so, these animals have do lots of adaptation, or passing on useful traits to their offspring so they can better survive.  Emperor penguins, the only birds who stick around to brave the long winter, have adapted to have a blubber layer that’s up to 3 cm (1.2 in) thick and four layers of downy feathers to keep them warm.  They live in large colonies so they can huddle together to keep their eggs warm, too.  


Some fish and mammals can dive deep into the ocean, where the temperature is more constant.  Some, like the mackerel icefish, have chemicals in their blood that’s similar to antifreeze in cars to prevent the blood from freezing.  Some go so deep that they develop deep-sea gigantism and grow to enormous sizes!  Scientists aren’t really sure why they grow so big, but some believe that it helps them
A giant Patagonian Toothfish captured by NOAA scientists
in the Antarctic.  These fish live at 
depths between 45 m
(148 ft) and 3,850 m (12,631 ft) below the surface.
Via 
http://www.nmfs.noaa.gov/
withstand the enormous water pressure at those depths.  Some animals switch between shallow and deep waters, like the Antarctic krill, an important food source for many whales and fish.  They’re one of the largest population of animals on earth: their schools are so big that they can turn the water red!


Unfortunately, while these animals have become very good at surviving these cold temperatures, they are very sensitive to temperature changes.  It’s like if you were wearing a thick coat that you weren’t able to take off--if you went from playing in the snow to your warm house, you’d get very uncomfortable very quickly!  The climate around the world is rising due to global warming, so these animals are not only becoming uncomfortable, but the ice they live on is melting and their food sources are vanishing.  The Antarctic Treaty System was an agreement signed by many countries to make Antarctica a scientific reserve. This means that, in order to protect Antarctic animals, only scientists doing research are allowed to interact with them.  The countries involved in the treaty, however, can’t do much to stop the global temperature rise.  It’s important to fight global warming to preserve these amazing creatures!
Some researchers approach seals near McMurdo Station,
on the "New Zealand side" of Antarctica.  The seals are not used to seeing people,
so they're not scared at all!  Courtesy of Rachel Bowens-Rubin

Learn More...
...At the Cambridge Science Festival:
  • On Wednesday, April 20th, the Mass Audubon Habitat Education Center and Wildlife Sanctuary is hosting Animals and Plants: Use Your Eyes from 4pm-6pm.  Come learn about how some local animals have adaptations of their own!  Registration is required.
  • Interested in learning more about how the earth revolves and time is measured?  Drop by the Cambridge Library from 12m-4pm on Saturday, April 23rd, for a demonstration of an Annosphere.  It's an antique but very useful scientific instrument, and the demonstration is free!
...And online:


  • NASA’s Antarctic page for Students grades K-4:

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E. Rosser is a science writer and mechanical engineer currently wrapping up a degree at MIT. She loves hearing about different places all around the world--and writing about them makes her want to travel there! Last year she caught up with Rachel as she was coming back from Antarctica via New Zealand, and the trip gave her a serious travel bug. This summer, she plans to travel to Iceland or Switzerland. There will probably be fewer hobbits there...

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