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A New Ice Age?
barakn writes "Scientists have savaged the new movie The Day After Tomorrow, which depicts global warming causing a new ice age and freezing New York solid. The movie follows on the heels of a report to the Department of Defense in February, written by two guys who are not climatologists, about the implications of global warming triggering the growth of ice sheets in the northern hemisphere. There is a plausible theory which suggests that melting ice may release enough fresh water to halt circulation of warm water from the Gulf Stream, thus significantly cooling Europe and the east coast of North America. Note that this theory depends on melting ice, not growing ice, which may be one reason scientists find the ice age scenario so hard to swallow. New satellite evidence suggests a part of this circulation may already be slowing down. Those on the North American west coast will not have to worry about ice sheets, but changes in Arctic ice could mean the western drought will be permanent. For those of you who would rather do something before it's too late, iron seems to work, but the long-term ecological implications are still unknown."
I personally believe that all this supposed changes may eventually occur, but they are a normal cycle of the earth and be very gradual. If the human race mangaes to survive long enough, we will slowly change how we do things to meet these problems.
Regardless though, what is gonna happen will happen, and there is nothing we can do to change it. Worrying about such things seems pointless to me. The whole planet is going to be destroyed by the sun dying in about 5 billion years, why don't we worry about that as well?
Scientists are up in arms because this movie was written by paranormal talk show host Art Bell and alien abductee Whitley Strieber.
Today, it's like 59 degreees F.
If that recollection is true, then we're still in an "Ice Age" and should expect the world to be getting warmer if the "Ice Age" is in fact coming to an end.
Sorry if this doesn't fit into the "human == BAD, all_natural == GOOD" paradigm, but getting struck by lightning or eaten by a lion does fall into the "all_natural" category too...
Although accurate software models of the earth's climate and weather conditions don't exist. There is certainly the hardware to run it. The worlds most powerful supercomputer the Earth Simulator is designed to be able to accurately model the earth. Hopefully advances in software modelling will enable us to actually make good use of all that raw processing power.
Here's another.
Or you could just Google for paleotemperature among other things.
I read the parent's "plausible theory" in Scientific American.
Nothing in the world is more dangerous than sincere ignorance and conscientious stupidity.
Cold, salty water from the North Atlantic sinks far below and runs south. Far enough south that it brings back warmer waters north. This flow includes the Gulf Stream.
Climate research has shown that climate shifts have occurred over history in as little as a few years.
If enough ice melts and flows into the North Atlantic, it disrupts the cold saline flow, which disrupts the concomittent return warm flow. Which makes the Northern Hemisphere colder. Which brings on the Ice.
That's as simple as it gets and the ice record in Greenland bears this out.
Because, for example, the eruption of Mount St Helens put 1 Million tonnes of sulfur aerosols into the stratosphere - these are the things that have the most effect on the worldwide climate, the ash from volcanos is local effect only.
Now, a million tonnes sounds absolutely huge. But it is still only just over five times what, say, the State of Louisiana emits as sulfur dioxide every year.
So in other words - the US easily produces as much sulfur dioxide, and more, every year than the explosion of Mount St Helens.
Or put it this way - you get sulfur dioxide from burning fossil fuels. We mine, worldwide, billions of tonnes of coal every year (the US alone produces just under a billion). How much sulfur dioxide do you think all that lot produces? The answer is that a typical small coal-fired power station (100 MW) may produce from 20 000 up to 30 000 tons of sulphur dioxide a year. In other words, Mt St Helens is worth a measly 40 small coal-fired power stations. How many of them are there in the US alone?
This is a pretty strong argument that the higher lattitudes are temperate because of the regulating effects of the currents. Siberia is a frozen waste because it benefits from no nearby warm current, and the Sahara bakes while the Amazon is merely tropical because of the proximity to a regulating surface current. If the deep ocean current were disrupted, there is reasonable and significant doubt that a different suitable global ocean current system would develop to prevent the low lattitudes from turning into a planet-wide desert while the high lattitudes make Siberia look like a warm vacation spot.
Then it demonstrates in a fish tank how cold water currents cannot descend in fresh water as well as in salt water. This is exactly what happens near Iceland, where the warm Atlantic surface current hits Arctic waters and drops to the ocean floor to fuel the deep ocean current. Already they have scientific measurements to suggest that the deep ocean current is being fueled less now than it was 30 years ago, before which nobody understood the importance of salinity in the oceans and the deep ocean currents. This correlates to the alarming increase in icebergs which have broken away from the polar ice caps over the last few decades (something like a 500% increase, by the way.)
And the documentary takes only 60 minutes, including commercials.
Your entire post is, frankly, complete and utter bullshit.
Ever heard of deforestation? Or of CO2 released by burning fossil fuels? Don't you think these things have any effect on CO2 levels in the atmosphere?
Do you know how much CO2 has been released since the dawn of the industrial revolution? Or that in nature it sometimes only takes a change of a few percent here or there to have catastrophic effects on an ecosystem?
Do you know that the US produces and consumes 25 percent of the world's power and yet has only 4 percent of the world's population? Yet you think that the US has a negative effect on CO2 production?
Where did you learn all the crap that you're spouting? A Halliburton "fact" sheet?
"Accept that some days you are the pigeon, and some days you are the statue." - David Brent, Wernham Hogg
More accurately, the books the movie is based on were written by Bell and Strieber. They didn't write the screenplay (or at least they're not credited with it; Roland Emmerich and Jeffrey Nachmanoff are).
"Destroy science and religion. Science would re-emerge exactly the same; but not religion." - Penn Jillette, paraphrased
The Gulf of Mexico is a large tropical sea with very warm water. A major ocean current, called the Gulf Stream, carries warm water from the Gulf up the east coast of the United States, starts to curve to the east as it passes Virginia, makes a sharper turn east near Cape Cod, heads straight for Ireland and Britain, turns south and heads down the French coast to Spain. The heat from the Gulf Stream warms northwestern Europe, and is the reason why London is as far north as Quebec and Moscow, but doesn't get 4 meters of snow every winter.
The mechanism that causes the Gulf Stream to flow is that cold water is denser than warm water. The arctic water up near Greenland and Iceland sinks and the warmer, less dense water from the Gulf of Mexico flows up to take its place.
However, salinity also affects water density. If enough fresh water from the ice cap melts and flows into the area around Newfoundland-Greenland-Iceland-Scotland, the water won't be dense enough to sink. Therefore the warm water will stop flowing north from the Gulf of Mexico.
Now London gets 4 meters of snow. Scandanavians laugh at them.
Of course, this will also cause the ice cap to stop melting in this area, but it will take quite a long time to "prime the pump", perhaps several thousand years. In the meantime, the northeastern United States and Northwestern Europe experience an "Ice Age" where their climate more closely resembles the climate of Russia at similar lattitudes.
You can, just go to http://www.coasttocoastam.com/ Cheers.
Actually, the US does have vast streches of forests (that are growing, not shrinking), though I wouldn't call them secret. The US has very low net carbon emmissons, compared to countries in Europe. One of the things the US wanted in Kyoto, but didn't get, was credit for CO2 absorbtion. (The other was a CO2 trading market, which didn't get added until the US dropped Kyoto like a bad habit) In other words, the US wanted to focus not just on CO2 emmissions, but on net contribution of CO2.
----- Question authority, but not ours. Hate the man, but we're not him.
Is it even legitimate from a mathematical-modeling viewpoint to talk about long-term average behavior?
Indeed, in a formal sense it is not easy to make a distinction between climate and weather. The casual statement "climate is the statistics of weather" becomes formally unsatisfactory when one starts to talk about climate change .
Nevertheless, I hope you will admit that I am saying something both meaningful and true when I say that the climate of Kansas City Missouri is more variable than that of Portland Oregon. How to cast this into a formal mathematical statement is not obvious, but probably not relevant for the current discussion. Whether it ought to be a practical issue for the field is something I've wondered about, but I don't think it's a current topic.
Interestingly, "climate" is conceptually better defined in our complex models than in the real world, because our models have finite sets of forcings and of free variables, and thus a clearer distinction between intrinsic and extrinsic variability than the real world does.
The prediction you make about 2304 is reasonable, but hardly long-term by geological standards.
Actually, the prediction is robust for any location at 40 degrees north latitude, at any date, on physical grounds, as long as the atmosphere is not almost totally opaque to incoming shortwave radiation (a.k.a. "sunshine") as on Venus.
I simply use it to illustrate that the predictability horizon of weather (defined as preturbations about the climatological mean) does not amount to a predictability constraint on the climate itself. I will make the same assertion for 30,000 years in the future, if you assure me that "Chicago" will be meaningful that far into the future (which I very much hope will be the case!)
I understand this doesn't go directly to your question, which is mathematical rather than physical. Climate is definitely not stationary, and quite possibly not even ergodic.
Climate is easy to define formally in our models though, much more so than in the real world. Our models can do multiple realizations of a particular year, based on specific boundary conditions and forcings. We capture enough of the variability in these models that the realizations differ. We treat the variations among these realizations as stochastic weather and the commonalities as deterministic climate.
In the real world, as opposed to in models, there is only one realization, and in fact, no clear distinction between intrinsic and extrinsic processes. So our meta-model, our model of the model, is difficult to justify formally.
In practice we don't dwell on this much. We just treat the real world as a superposition of chaotic dynamic variability (an unpredictable part) and deterministic climate change which sets up the statistical properties of the chaos.
In the simple chaotic dynamics view, weather is the state of the system (the wandering dot), and climate is the shape of the set of permissible trajectories (the whole phase diagram). Things aren't necessarily that simple in fact, but we don't have a better way of addressing the issue. Ultimately, we aren't trying to prove theorems, we're trying to elucidate complex physics, and this view appears to be both necessary and sufficient for most of our purposes.
mt
Possibilities are not probabilities are not certainties.
Not 18,185,947,580,800 kWh. From your own numbers it should be 18,185,947,580,800,000 kWh available from solar (you were off by a factor of 1000).
Completely moving to solar electric would be very expensive with current technology, and use a lot of land, but it probably could be done.
a,e,i,o,u and sometimes w and y (at be if of up cwm by)