What you should be meaning to ask is, "Why is the ice around Antarctica at such a great extent?"
Because ice on the Antarctic continent is not "at such a high level".
There could be several reasons.
- Land ice is melting, running into the ocean. Since it's fresh water, it tends to float on top of the salt water, which is heavier. And, since it doesn't have salt, it freezes at a higher temperature than salt water.
- The warm atmosphere outside of Antarctica is lighter than the cold Antarctic air mass. So the lighter warm air rises, pulling the cold Antarctic are farther away from the continent, allowing more ocean water to freeze.
However, the true answer is that weather and climate is not a straight line science. It varies. So while there is a greater ice extent this year, that's not going to happen every year, and one shouldn't make any assumptions about long term climate based on what happened this year.
There are some current theories that could explain this. Firstly, on the land, Antarctica is losing something like 100 billion tonnes of ice a year.
http://www.sciencemag.org/content/338/61...
This extra loss of ice means that cold fresh water is flooding into the oceans around. Fresh water floats on top, and fresh water is easier to freeze than salty water.
Another possibility, is that winds around Antarctica have got stronger. This spreads out the ice, so it covers a wider area. Part of the reason the winds have got stronger is because of the ozone hole. Normally ozone absorbs sunlight and heats up the air high in the sky. When there's less of it, the air high up cools down, and the temperature difference between the Antarctic and the areas nearby gets bigger. Bigger temperature differences drive stronger winds.
http://www.nature.com/ngeo/journal/v5/n1...
http://onlinelibrary.wiley.com/doi/10.10...
According to one study, winter temperatures have gone up around Antarctica. But if you go from -18.6 C to -18 C, you aren't going to stop any freezing.
This is still not completely solved, but the evidence shows it's a pretty good bet that changing wind patterns combine with super-low temperatures to explain much of what's going on. This is still consistent with global warming.
It has to do with ocean currents. Why is the sea level rising so dramatically, the level of sea ice down to less than half what it was in 1800, and the land ice melting at such a rate, if there isn't global warming?
Antarctic Land ice or Sea ice? There's a difference.
Alph has it. The areal extent has been increasing while the ice shelf has been melting from below. If you had a meatball and flattened it into a hamburger patty, would you say that you had more meat?
It is funny how alarmists say it is land and not sea ice and think they have answered the question. I guess for them it makes sense for a warming world to have increased ice on the land and yet they whine about receding glaciers. You would think alarmists heads would spin with the contradictions that come out of their mouths but they keep trudging on in the knowledge that they are the smartest people in the room because they care more. It is astonishing really.
It seems that global warming is only over half the globe which begs the question about CO2 concentrations in the southern hemisphere. I guess in their world, CO2 only affects the industrialized capitalist north. who knows?
CR, care to explain why warming should cause sea ice to increase particularly when your ilk are suggesting the warming is hidden in the ocean. Instead of being led around like a sheep, learn to think for yourself for once. When you break free of your cult, you will learn that everything you read in left wing blogs isn't true. In fact, most of it is garbage.
it's in the shade
while the arctic continues to melt
Jim Z
Yes, it's most amusing, given that it is the land ice that is shrinking and the sea ice that is growing.
nature always finds a way to balance itself out
13 years ago, global warming scientists were telling that us that the Antarctic would be ice free in 10 years, and our children wouldn't know what ice would be because it would be a rare and unusual occurrence. However the ice hasn't cooperated with the climate models as the ice has gained in mass every year since it was measured and is now gaining at the remarkable rate of 1.5% per decade. Soon the ice could cover the Magellan Straight, blocking the ocean currents between the Pacific and Atlantic Oceans, and could user in a new ice age.
because we have been adding ice to the oceans from soda machines to make up for global warming
Because global warming is not a condition, it's an agenda for milking money out of governments for worthless research.
warmer air is pushing the cold air and concentrating it
sea ice is not land ice. you need to check the total volume change.
