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Stronger Winds Explain Puzzling Growth of Sea Ice In Antarctica
vinces99 writes "As NOAA announces a new record for the extent of sea ice in Antarctica, a new modeling study to be published in the Journal of Climate shows that stronger polar winds lead to an increase in Antarctic sea ice, even when Earth's overall climate is getting warmer. The study (abstract) by Jinlun Zhang, a University of Washington oceanographer, shows that stronger westerly winds swirling around the South Pole can explain 80 percent of the increase in Antarctic sea ice volume during the past three decades. The polar vortex that swirls around the South Pole is not just stronger than it was when satellite records began in the 1970s, it also shoves the sea ice together to cause ridging. Stronger winds also drive ice faster, which leads to still more deformation and ridging. This creates thicker, longer-lasting ice, while exposing surrounding water and thin ice to the blistering cold winds that cause more ice growth. A computer simulation that includes detailed interactions between wind and sea shows that thick ice — more than 6 feet deep — increased by about 1 percent per year from 1979 to 2010, while the amount of thin ice stayed fairly constant. The end result is a thicker, slightly larger ice pack that lasts longer into the summer."
This isn't the northern sea ice. The Antarctic sea ice has been trending slowly upwards, overall. With strong loss near the peninsular.
The global average temperature is still trending up. But to consider things a bit more accurately:
Think of the earth as one big system. For the most part, energy only comes in and goes out through the atmosphere. At the moment, gases in the atmosphere are causing the earth to radiate slightly less energy out into space than it takes in. Before we got started dumping CO2 into the atmosphere, earth was in a state of equilibrium, but that equilibrium has been disrupted. Provided we can stabilize that amount of CO2 in the atmosphere, we should reach a new state of equilibrium, and with any luck, it will be similar to the one we were in before.
If not, then there are a lot of things that could happen, and most of them aren't good.
Extra energy in the atmosphere often becomes heat. This is pretty much the simplest thing that can happen.
Extra energy can also go into warming the land. This seems like a good thing, because the land can act as a buffer by absorbing energy from the atmosphere, but if the land gets too warm and old swamps start to thaw out, large quantities of methane will be released into the air, which will further decrease the earth's ability to radiate excess energy.
Extra energy can also cause increased evaporation of water from the ocean, which increases cloud cover and precipitation. This is why snow isn't evidence that global warming has somehow reversed. That being said, cloud cover and snow are both white, which increases the amount of light reflected back out into space. The trouble is, we're not going to reach an equilibrium state until the amount of greenhouse gasses in the atmosphere level off. Increased precipitation might stave off big rises in temperature for a while. Or, it's possible that precipitation will increase so much that the ice sheets will expand very rapidly, causing the earth to radiate away *more* energy than it takes in, which could set off an ice age, which would be really bad. Or, it's possible that cloud cover and precipitation aren't enough to counteract the warming effect at all, in which case we'll continue to see the heating that we're seeing now.
In any case, as long as we're increasing the amount of greenhouse gases in the air, we're pushing things further and further out of equilibrium. If we can't get things under control, it is inevitable that things will eventually swing wildly out of control, because there are only so many potential buffer effects that might absorb or reflect the excess energy. Take the aforementioned cloud cover and precipitation. Since we can increase the greenhouse gases in the air indefinitely, even if cloud cover and precipitation are enough to equalize things for a while, eventually they aren't going to be enough. Or, as I said earlier, they might spiral out of control and become too much. We don't know for sure. But eventually, bad things will happen.
Maybe if we're lucky it'll be in a few hundred years. If we're not so lucky, maybe a few decades.
I work in a government remote-sensing role, where we generate a lot of derived data (backed up by ground truth data we collect in the real world to compare against).
We've got a bit of an unspoken law about models: they're shit.
No matter how hard you try, when you attempt to model/simulate large-scale natural phenomena - where you have so many different systems affecting one another, and so much to keep track of - you end up with a realistic workload of dozens of man years of scientific development just to come up with the mathematical model (ignoring the software side to actually simulate it on a computer).
The end result of this is: People simplify, and then simplify again - to take what should take the better part of a couple years, and do it in 6 months to get reviewed and presented at their next conference of choice; ultimately coming up with useless results - which on the surface if they're lucky may look valid, but just end up proving to be horribly incorrect in a different spatial or temporal domain (eg: on another continent, or in your case - a year later...)
There's are of course a few exceptions to this rule (typically around radiative transfer models, and flood plain modeling - and a few other places where you're either working at such a low level and scale or an incredibly well studied field (eg: radiation/light physics has centuries of scientific backing)).
Needless to say though, 'climate change' is a worst case scenario here - large scale, many complicated systems, and in aggregate everything needed to model this accurately doesn't have the solid scientific understanding.
I predict humans will observe the earth warming, then cooling, then warming, etc.. in a cycle that repeats itself over and over again with varying frequencies and amplitudes until such time humans become extinct and are replaced by a more evolved species that lacks the pretense of understanding a system as complex as the earth's macro climate.
Equilibrium? Extra energy often becoming heat? Ancient swamps thawing? Additional atmospheric water vapor helps cooling?, Apocalyptic heat death in a few decades?
I'm really not trying to be mean to you, because we need to stop poisoning ourselves. But posts like yours do not help. Your post is a "deniers" wet dream. It's makes people who want to be better stewards of the planet look like crazy people.
The temperature trends look like they are going up at an insane rate if you look at the last 500, or 1000 years. But if you look at the last 200K years of half or million years, it's debatable.
The earth is not and hopefully will never be in a state of equilibrium any time soon. Do you know what is in a much closer state of atmospheric equilibrium? The moon is a pretty good place to look. Mars isn't bad either. I don't know about you, but I like our atmosphere. As long as we have it and there are living things on this planet, it will remain that way. Hopefully for a very long time.
I'm not even going to get started on the heat energy thing
I assume the link above is what you are referencing in regards to as "old swamps". At least that's what I'm guessing as I've never heard of the danger of thawing swamps. Plus there's a hell of a lot more methane in those formations than any swamp. It's also unknown if that methane will be released with rising temperature. But like you, I'd rather not find out. I would much prefer it remain an academic debate than see it put to the test.
There is strong evidence for the Albedo effect. However the link regarding atmospheric water vapor also seems to provide compelling evidence that water vapor in the atmosphere is also a strong greenhouse gas.
I understand that trying to make this problem something dire that will affect most of us in our lifetimes seems like a way to make others more motivated. But when it doesn't happen in the ridiculously short time-frames you are using, it makes most people call BS. Spreading this amount of misinformation is really not helping. I apologize for sounding like an ass, but posts like yours make it too easy for those who don't give a shit to keep on not worrying about it.
Have you actually sat down and talked with an actual scientist in the field?
Instead of only reading laymans interpretations of what they say?
You might be surprised that they can actually answer all of the dumb questions.
Deniers usually attack a simplified view made to explain extremely complex things to layman and then find some holes in the simplificiation and then deny everything based on it.