Are current global warming effects reversible?

[TySixtus]

Let's suppose that tomorrow, human technology is zapped back to the level it was in 1300 AD. Would the current effects of global warming (melting ice shelves, increasing temps, the whole 9 yards) receed? Would they stop? Would ice again reform in the Arctic, or would it continue to melt?

Just curious... I watched "An Inconvenient Truth". Pretty depressing. :(

Ty

[Silent Acorns]

the time it takes an average CO2 molecule to leave the atmosphere is 200 to 500 years. This means that the current concentrations of CO2 will stay high for several centuries, after which things will start to return to "normal".

[David B]

Sure. Another Toba would overdo it, in fact. Another Tambora might fit the bill.

David B

[Loren Pechtel]

Let's suppose that tomorrow, human technology is zapped back to the level it was in 1300 AD. Would the current effects of global warming (melting ice shelves, increasing temps, the whole 9 yards) receed? Would they stop? Would ice again reform in the Arctic, or would it continue to melt?

Just curious... I watched "An Inconvenient Truth". Pretty depressing. :(

Ty

In time. There's a lot of inertia, though--it would warm for a while before going back to normal.

[jayh]

Let's suppose that tomorrow, human technology is zapped back to the level it was in 1300 AD. Would the current effects of global warming (melting ice shelves, increasing temps, the whole 9 yards) receed? Would they stop? Would ice again reform in the Arctic, or would it continue to melt?

Just curious... I watched "An Inconvenient Truth". Pretty depressing. :(

Ty

This is a big part of the problem. CO2 is so deep in every component of civilization, i would indeed bring us close to the stone age, of course that would then eliminate the possibilities of a cleaner technological future. A better approach would be mitigation of the situation, accepting that there will be higher than historic levels, and dealing with it.

As was pointed out frequently, the poor would be at risk in many parts of the world, but at present (other than extreme areas like Darfur) even the poorer parts of the world are supported somewhat by the world's CO2 economy:food production, medicine, transportation. Humans have been CO2 producers since the taming of fire, much smarter to learn to live with it.

[jayh]

the time it takes an average CO2 molecule to leave the atmosphere is 200 to 500 years. This means that the current concentrations of CO2 will stay high for several centuries, after which things will start to return to "normal".

That number sounds more like the number quoted for the freon type molecules (or CO2 in very high atmosphere). That does not sound correct for ground level CO2... do you have a cite?

[jayh]

Changing 'lifestyle'-- eliminate or reduce cooling, cut home heating to a bare minimum in 1 room, get some high efficiency car etc... you'll maybe reduce your 'footprint' by 30% maybe 40%.

But... if you forgoe chldren you will be making a REAL difference, several footprints instead of part of one... if you count the descendants for the next century you will be REDUCING YOUR CONTRIBUTION to the Carbon cycle by the EQUIVALENT OF DOZENS of footprints, not just a small part of one.

When it comes down to it, the single guy with a 20 room house and mega cars, but no kids is less of a carbon burden than the Prius driving organic farm family with 3 kids.]

[Newton's Cat]

Yes - provided we abandon Capitalism.

[Loren Pechtel]

Yes - provided we abandon Capitalism.

Taking us back to 1300 AD would be abandoning capitalism--it would blow us back to the early stone age after killing at least 99.99% of the human race.

[TySixtus]

Yes - provided we abandon Capitalism.

What does economy have to do with reversing environmental damage? One is a question about society, the other about the laws of nature and the durability of certain gasses. In other words, icecaps won't reform because we give the masses control of the means of production.

Ty

[Silent Acorns]

When it comes down to it, the single guy with a 20 room house and mega cars, but no kids is less of a carbon burden than the Prius driving organic farm family with 3 kids.]

This is simply false, and it's not even close.

[Gracchus]

Whether the climate change is reversible depends on whether we have reached the "tipping point". Were it not for greenhouse gases we might be entering another ice age. Chaos theory was discovered during weather modeling experiments, so a very small change in initial conditions can produce a very big change in climate. And a large change is even more likely to produce a drastic, long-term change of conditions that could be hard or impossible to reverse.

My guess is that whatever we do, we are going to experience wild climatic oscillations that may return to our familiar, accustomed equilibrium or may settle at a new equilibrium point. In any case, there is going to be a great dying, and the human race may very well go extinct. Our suggested epitaph: TOO STUPID TO LIVE.

:wave:

[Silent Acorns]

Chaos theory was discovered during weather modeling experiments, so a very small change in initial conditions can produce a very big change in climate. And a large change is even more likely to produce a drastic, long-term change of conditions that could be hard or impossible to reverse.

The first comment is true, but the second doesn't follow. The third is true of just about any system.

My guess is that whatever we do, we are going to experience wild climatic oscillations that may return to our familiar, accustomed equilibrium or may settle at a new equilibrium point.

Climate is not the sort of thing you should casually apply to phrases like "wild oscillations ". By definition, climate refers to long term averages and trends over scales like 30 years. Just being able to detect half an oscillation (say the rising or falling limb) in a person's lifetime is pretty wild by climatic standards.

Climate is also not something that lends itself to "equilibrium points" because very few major factors are stable over these time scales.

In any case, there is going to be a great dying, and the human race may very well go extinct. Our suggested epitaph: TOO STUPID TO LIVE.

At the extreme, climate change/global warming might devestate modern civilizations. Going extinct is not even a remote possability. The only realistic things that could do that are a meteor collision or full-scale nuclear war.

[ashaktur]

But... if you forgoe chldren you will be making a REAL difference, several footprints instead of part of one... if you count the descendants for the next century you will be REDUCING YOUR CONTRIBUTION to the Carbon cycle by the EQUIVALENT OF DOZENS of footprints, not just a small part of one.

When it comes down to it, the single guy with a 20 room house and mega cars, but no kids is less of a carbon burden than the Prius driving organic farm family with 3 kids.]

I love this argument - it is flawed in so many ways. You think you are doing the world a favour by not having kids but have you considered:
- the world would be better without your carbon footprint as well
- technology changes over time, so your grandkids etc may have no carbon footprint at all

When it comes down to it, population contol advocates are all selfish hypocrites (re point 1) and fascists (because they want to impose their stupid views on normal people).

[ashaktur]

My guess is that whatever we do, we are going to experience wild climatic oscillations that may return to our familiar, accustomed equilibrium or may settle at a new equilibrium point.

Climate is dynamic not static. It does not have equilibrium points.


Our suggested epitaph: TOO STUPID TO LIVE.


Speak for yourself.

[Steve Weiss]

Taking us back to 1300 AD would be abandoning capitalism--it would blow us back to the early stone age after killing at least 99.99% of the human race.

Many global warmers would rejoice at this outcome.

[jayh]

I love this argument - it is flawed in so many ways. You think you are doing the world a favour by not having kids but have you considered:
- the world would be better without your carbon footprint as well
- technology changes over time, so your grandkids etc may have no carbon footprint at all

When it comes down to it, population contol advocates are all selfish hypocrites (re point 1) and fascists (because they want to impose their stupid views on normal people).

The argument was tongue in cheek to make a point-- I am NOT suggesting any form of mandatory population control.

But the point is, simply that the SINGLE BIGGEST FACTOR in human change to the climate is population. Current lifestyles and technology with 1B would have much lower numbers. We need to accept the fact that high carbon is with us and will be for a long long time and solutions need to be worked around that fact. [And the fact remains that your 10 grandchildren will have far more of a footprint than all the 'conservation' you do in your lifetime.]

[TySixtus]

Could some kind of carbon scrubber work? Or the problem simply too big for it, at this point?

Ty

[skepticalbip]

the time it takes an average CO2 molecule to leave the atmosphere is 200 to 500 years. This looks like one of those meaningless factoids that are inserted into discussions to frighten children. I have no idea how the mean period of time a typical CO2 molecule would remain in the atmosphere is derived but it is not specific molecules that is important - it is the concentration. Approximately 180 billion tons of CO2 per year (IIRC) are sequestered through photosynthesis, reef building, etc. Without the CO2, these processes stop.

This means that the current concentrations of CO2 will stay high for several centuries, after which things will start to return to "normal". A conclusion drawn with the assumption that, for example, an oak tree can not possibly use a molecule of CO2 until it has remained in the atmosphere for several hundred years. - An assumption which, incidentally, I reject.

[ppnl]

This looks like one of those meaningless factoids that are inserted into discussions to frighten children. I have no idea how the mean period of time a typical CO2 molecule would remain in the atmosphere is derived but it is not specific molecules that is important - it is the concentration. Approximately 180 billion tons of CO2 per year (IIRC) are sequestered through photosynthesis, reef building, etc. Without the CO2, these processes stop.
A conclusion drawn with the assumption that, for example, an oak tree can not possibly use a molecule of CO2 until it has remained in the atmosphere for several hundred years. - An assumption which, incidentally, I reject.



Um, its an equilibrium thing. If co2 had a short average residence time in the atmosphere of like three days then no matter how far you pushed it out of equilibrium it would start heading back to equilibrium after three days. If its residence time is a thousand years then thats how long it will take to come back down to equilibrium. Its a measure of how fast the system will change.

[ppnl]

Could some kind of carbon scrubber work? Or the problem simply too big for it, at this point?

Ty

It makes little sense to talk about scrubbers until we stop burning fossil fuels. If we do that then in principle we could take carbon out of the atmosphere. But I suspect this will only be practical if energy is very very cheap.

[skepticalbip]

Um, its an equilibrium thing. If co2 had a short average residence time in the atmosphere of like three days then no matter how far you pushed it out of equilibrium it would start heading back to equilibrium after three days. If its residence time is a thousand years then thats how long it will take to come back down to equilibrium. Its a measure of how fast the system will change.If all sources of atmospheric CO2 ceased tomorrow then the world's ecosystems would be seriously threatened immediately. Current CO2 use by the bio-system is over one hundred and fifty billion tons/yr and the total mass of CO2 in the atmosphere is something like two billion tons. (I'll have to double check the math but that is what it looks like taking the total mass of the atmosphere, the percentage of CO2 in the atmosphere, and the molar mass of CO2)

The carbon cycle is a dynamic system, not static like you seem to assume.

[Gracchus]

Gracchus View Post
Chaos theory was discovered during weather modeling experiments, so a very small change in initial conditions can produce a very big change in climate. And a large change is even more likely to produce a drastic, long-term change of conditions that could be hard or impossible to reverse.

The first comment is true, but the second doesn't follow. The third is true of just about any system.

There were only two comments. Google “sensitivity to initial condition” or the “butterfly’s wing effect”. Chaos theory is about how very small changes can lead to unpredictable and sometimes very large effects.


My guess is that whatever we do, we are going to experience wild climatic oscillations that may return to our familiar, accustomed equilibrium or may settle at a new equilibrium point.

Climate is not the sort of thing you should casually apply to phrases like "wild oscillations ". By definition, climate refers to long term averages and trends over scales like 30 years. Just being able to detect half an oscillation (say the rising or falling limb) in a person's lifetime is pretty wild by climatic standards.

A hard freeze after bud formation can wipe out crops. Too little or too much rain can wipe out agricultural production over a huge area. For human purposes any long series of such events would be sufficiently “wild” to produce widespread famine and the inevitable attendant social disorders.

Where have all the flowers gone? They perished for lack of pollinators.

Disease carrying insects can move into new areas, mowing down non-resistant species. And climate is about patterns more than averages. What if we have “el niño” every year, or what if it vanished entirely? Suppose the jet stream changed course, or failed to change from a summer to winter pattern, disrupting storm tracks? During the “little ice age” a massive discharge of glacial melt disrupted the Gulf Stream. Warming in the arctic ocean and melting permafrost are very likely going to discharge massive amounts of methane and CO2 into the atmosphere. That will take a very long time indeed to reverse itself, and indeed, a reversal might never occur.

Climate is also not something that lends itself to "equilibrium points" because very few major factors are stable over these time scales.

Climate is dynamic not static. It does not have equilibrium points.

In nature, all equilibrium is dynamic. Human culture however, depends upon climatic stability, and within certain ranges. If climate reaches a new stability outside those ranges, or if it never stabilizes, we perish.


In any case, there is going to be a great dying, and the human race may very well go extinct.

At the extreme, climate change/global warming might devestate modern civilizations. Going extinct is not even a remote possability. The only realistic things that could do that are a meteor collision or full-scale nuclear war.

99% of all species that ever lived are now extinct. Most did not perish because of a global extinction event, but succumbed quietly to less dramatic changes. History would indicate that widespread starvation leads to social instability and war. Now that mankind has nuclear, chemical, and biological weapons of mass destruction it is almost inevitable they will be used in desperate and extreme conditions. And what survives a mass extinction event need not be anything like “intelligent”. I am not saying it will happen, but it is a real risk.

Global climactic change entails far more than just a rise in average temperature. It means famine, pestilence and war.

:wave:

[Silent Acorns]

This looks like one of those meaningless factoids that are inserted into discussions to frighten children. I have no idea how the mean period of time a typical CO2 molecule would remain in the atmosphere is derived but it is not specific molecules that is important - it is the concentration. Approximately 180 billion tons of CO2 per year (IIRC) are sequestered through photosynthesis, reef building, etc. Without the CO2, these processes stop.

You're only proving that you don't know anything about the subject. The mean lifetime is calculated by taking the current mass of CO2 in the atmosphere and dividing it by the rate at which CO2 is taken out of the atmosphere (by the processes you mention). If you do this calculation you get a number like 200 to 500 years (depending on whose sequestation numbers you use).

CO2 represents about 0.04% of the atmosphere (on a molar basis) this works out to something like 30 trillion tonnes. Using your 180 billion t/y number (which I suspect is a high estimate) you get a mean residence time of 170 years. If you did the same calculation for water vapor you get a mean residence time of one week.

This is not a menaingless factoid, it's one of the two or three most important factors of CO2's contribution to global warming. It's the reason it's even possible for human activity to double CO2 concentrations. It's the reason water vapor is not a significant factor in future global warming. It's the reason we can be confident that temperatures will rise for a long time and stay high even if we reduce emissions now.

A conclusion drawn with the assumption that, for example, an oak tree can not possibly use a molecule of CO2 until it has remained in the atmosphere for several hundred years. - An assumption which, incidentally, I reject.

This last sentence is about as ignorant a statement as I could imagine.

[Silent Acorns]

There were only two comments. Google “sensitivity to initial condition” or the “butterfly’s wing effect”. Chaos theory is about how very small changes can lead to unpredictable and sometimes very large effects.

I know what the butterfly effect is, but it's not relevent to global climate, or at most, it's extremely marginal.

A hard freeze after bud formation can wipe out crops. Too little or too much rain can wipe out agricultural production over a huge area. For human purposes any long series of such events would be sufficiently “wild” to produce widespread famine and the inevitable attendant social disorders.

I'm not saying that global warming won't have severe consequences. I'm saying that long term global average temperature won't oscillate wildly (i.e. go up and down by several degrees over a short period of time).

During the “little ice age” a massive discharge of glacial melt disrupted the Gulf Stream. Warming in the arctic ocean and melting permafrost are very likely going to discharge massive amounts of methane and CO2 into the atmosphere. That will take a very long time indeed to reverse itself, and indeed, a reversal might never occur.

I know about this. It's an important possibility, and it's worrysome. But it's still not an "oscillation". It's just a positive feedback mechanism that'll make warming even worse.

In nature, all equilibrium is dynamic. Human culture however, depends upon climatic stability, and within certain ranges. If climate reaches a new stability outside those ranges, or if it never stabilizes, we perish.

You're preaching to the choir here. Except for the "perish" part. Sure, if it never stabilizes but this is a remote possibility at the extreme of all extremes.

99% of all species that ever lived are now extinct. Most did not perish because of a global extinction event, but succumbed quietly to less dramatic changes. History would indicate that widespread starvation leads to social instability and war. Now that mankind has nuclear, chemical, and biological weapons of mass destruction it is almost inevitable they will be used in desperate and extreme conditions. And what survives a mass extinction event need not be anything like “intelligent”. I am not saying it will happen, but it is a real risk.

I'm only saying that global warming is not a human extinction mechanism we should worry about. It's true that it has the potential to devestate local or even global economies but this is a long way from extinction.

Global climactic change entails far more than just a rise in average temperature. It means famine, pestilence and war.

I agree, but again, this doesn't entail extinction.

[ppnl]

If all sources of atmospheric CO2 ceased tomorrow then the world's ecosystems would be seriously threatened immediately. Current CO2 use by the bio-system is over one hundred and fifty billion tons/yr and the total mass of CO2 in the atmosphere is something like two billion tons. (I'll have to double check the math but that is what it looks like taking the total mass of the atmosphere, the percentage of CO2 in the atmosphere, and the molar mass of CO2)

The carbon cycle is a dynamic system, not static like you seem to assume.


Uh....

I'm having a little trouble deciding on how to respond to this.

First I understand that the carbon cycle is a dynamic system. That was my whole point. You have processes that put co2 in the atmosphere and you have processes that remove it. These processes will reach equilibrium as long as those processes do not change. The average residence time gives us an idea of how long it will take the atmosphere to return to equilibrium after it is pushed out of equilibrium.

Two billion tons total in the atmosphere? Better check your math. I think humans burn like three times that much coal every year.

And what question does this address anyway? Who is talking about eliminating all sources of co2? If we just make stuff up we can change the co2 level as fast as we wish.

[Gracchus]

There were only two comments. Google “sensitivity to initial condition” or the “butterfly’s wing effect”. Chaos theory is about how very small changes can lead to unpredictable and sometimes very large effects.

I know what the butterfly effect is, but it's not relevent to global climate, or at most, it's extremely marginal.

It is not relevant because …?




A hard freeze after bud formation can wipe out crops. Too little or too much rain can wipe out agricultural production over a huge area. For human purposes any long series of such events would be sufficiently “wild” to produce widespread famine and the inevitable attendant social disorders.

I'm not saying that global warming won't have severe consequences. I'm saying that long term global average temperature won't oscillate wildly (i.e. go up and down by several degrees over a short period of time).

The average will not oscillate, it will go up. What will oscillate are the extremes, and the seasonal weather patterns. Early springs will be nipped in the bud, preventing fruiting. The average will go up, but the maximums will be greater and more common and the minimums lower but more scarce.



During the “little ice age” a massive discharge of glacial melt disrupted the Gulf Stream. Warming in the arctic ocean and melting permafrost are very likely going to discharge massive amounts of methane and CO2 into the atmosphere. That will take a very long time indeed to reverse itself, and indeed, a reversal might never occur.

I know about this. It's an important possibility, and it's worrysome. But it's still not an "oscillation". It's just a positive feedback mechanism that'll make warming even worse.

Again, the oscillation will not be in the average temperature, it will be in minimums, maximums, and the patterns of atmospheric and ocean currents. If you prefer the terms "instability" and "unpredictability" to "oscillations" I won't quibble.



In nature, all equilibrium is dynamic. Human culture however, depends upon climatic stability, and within certain ranges. If climate reaches a new stability outside those ranges, or if it never stabilizes, we perish.

You're preaching to the choir here. Except for the "perish" part. Sure, if it never stabilizes but this is a remote possibility at the extreme of all extremes.

Most of the planets we know about are "extreme of all extremes". We know of exactly one planet where we can survive.

There are huge deposits of methane under the polar oceans and in the tundra, which will be released as temperatures rise. Methane is also a greenhouse gas, and will form even more CO2 and water vapor as it oxidizes.

How many humans will survive maximum summer temperatures of > 130°F in the temperate zones? What will happen to the tropics when the equatorial rain forests become deserts, and the taiga is pushed to the arctic ocean? The richest growth of phytoplankton is where cold ocean currents well up and around the poles. When that bloom dies what will happen to the CO2 cycle? What will happen to the oxygen level of the atmosphere? There are species that might survive in a low O2 high CO2 environment but Homo sapiens isn't one of them.


99% of all species that ever lived are now extinct. Most did not perish because of a global extinction event, but succumbed quietly to less dramatic changes. History would indicate that widespread starvation leads to social instability and war. Now that mankind has nuclear, chemical, and biological weapons of mass destruction it is almost inevitable they will be used in desperate and extreme conditions. And what survives a mass extinction event need not be anything like “intelligent”. I am not saying it will happen, but it is a real risk.

I'm only saying that global warming is not a human extinction mechanism we should worry about. It's true that it has the potential to devestate local or even global economies but this is a long way from extinction.

You’re not thinking about the effect that global warming will have on atmospheric chemistry.


Global climactic change entails far more than just a rise in average temperature. It means famine, pestilence and war.

I agree, but again, this doesn't entail extinction.

Extinction is a real possibility, although admittedly not a certainty, (Unpredictability is inherent in chaotic systems like weather.), but those who live through the next centuries, if any do, will almost certainly not live well. And if they do live through it, they might not be recognizably human in any sense of the word.


:wave:

[Steve Weiss]

It is not relevant because …?




The average will not oscillate, it will go up. What will oscillate are the extremes, and the seasonal weather patterns. Early springs will be nipped in the bud, preventing fruiting. The average will go up, but the maximums will be greater and more common and the minimums lower but more scarce.



Again, the oscillation will not be in the average temperature, it will be in minimums, maximums, and the patterns of atmospheric and ocean currents. If you prefer the terms "instability" and "unpredictability" to "oscillations" I won't quibble.



Most of the planets we know about are "extreme of all extremes". We know of exactly one planet where we can survive.

There are huge deposits of methane under the polar oceans and in the tundra, which will be released as temperatures rise. Methane is also a greenhouse gas, and will form even more CO2 and water vapor as it oxidizes.

How many humans will survive maximum summer temperatures of > 130°F in the temperate zones? What will happen to the tropics when the equatorial rain forests become deserts, and the taiga is pushed to the arctic ocean? The richest growth of phytoplankton is where cold ocean currents well up and around the poles. When that bloom dies what will happen to the CO2 cycle? What will happen to the oxygen level of the atmosphere? There are species that might survive in a low O2 high CO2 environment but Homo sapiens isn't one of them.



You’re not thinking about the effect that global warming will have on atmospheric chemistry.



Extinction is a real possibility, although admittedly not a certainty, (Unpredictability is inherent in chaotic systems like weather.), but those who live through the next centuries, if any do, will almost certainly not live well. And if they do live through it, they might not be recognizably human in any sense of the word.


:wave:

How much time is left? I'd like to do a few things before it's all over.

[gracebkr]

Let's suppose that tomorrow, human technology is zapped back to the level it was in 1300 AD. Would the current effects of global warming (melting ice shelves, increasing temps, the whole 9 yards) receed? Would they stop? Would ice again reform in the Arctic, or would it continue to melt?

Just curious... I watched "An Inconvenient Truth". Pretty depressing. :(

Ty

Don't believe politicians. They always have a reason to lie. Al Gore uses 20 times more energy than the national average. The truth is that the earth has gone through this process before, it is not the first time earth experienced a global warming. Didn't I read somewhere Mars was also going through a global warming?

http://www.tennesseepolicy.org/main/article.php?article_id=367
http://news.nationalgeographic.com/news/2007/02/070228-mars-warming.html
http://www2.le.ac.uk/ebulletin/features/2000-2009/2004/12/nparticle-vkt-hgf-t4c

[Steve Weiss]

Don't believe politicians. They always have a reason to lie. Al Gore uses 20 times more energy than the national average. The truth is that the earth has gone through this process before, it is not the first time earth experienced a global warming. Didn't I read somewhere Mars was also going through a global warming?

http://www.tennesseepolicy.org/main/article.php?article_id=367
http://news.nationalgeographic.com/news/2007/02/070228-mars-warming.html
http://www2.le.ac.uk/ebulletin/features/2000-2009/2004/12/nparticle-vkt-hgf-t4c

Be prepared to be denounced as a denialist. By the way, why does a Roman Catholic participate on this site? Wouldn't that be a sin?

[Musing Man]

Be prepared to be denounced as a denialist. By the way, why does a Roman Catholic participate on this site? Wouldn't that be a sin?

I dare to think that this forum is open for everyone who wants to know more.
Unfortunately, this is not your case.
You are well stuck in your rigid, non-realistic convictions, I'm afraid.
No amount of objective data will change your mind.
But feel free to argue that, if you can.


And to address gracebkr's concern, yes, Al Gore may use 20 times as much energy as the average consumer (any source for that?), but he's doing it as clean as one can get.

In other words, and please excuse my gruesome comparison, it doesn't matter how much and/or how often you shit, it matters what you do with your shit. Gore doesn't watch the flies over it, as Bush does.

As for the topic, no, the effects are not reversible.
Future's new equilibrium will be different than our historic "normal". Maybe not much, but different nonetheless.

[Gracchus]

How much time is left? I'd like to do a few things before it's all over.

One of the inconveniences of chaotic systems is their unpredictability. It does seem that the polar ice is melting twice as fast as models predicted. Children now growing up will live, and die, in a very different world.

:wave:

[Hawxhurst]

An older pop piece but I like it.

http://www.wired.com/wired/archive/14.12/start.html?pg=3


The problem is inertia; the changes we have wrought in the atmosphere will play out over decades (or longer) whether we junk all the SUVs tomorrow or not.

That's why it makes sense to start thinking seriously about radical countermeasures. One of the biggest boosts to the idea of climate manipulation came last summer from Paul Crutzen, an emeritus at the Max Planck Institute for Chemistry. ...

Crutzen's not crazy, and he's no renegade terraformer. "Until a few years ago, I would also have been against the idea," he recently told an Australian newspaper.

His journal article – and his clout – gave geoengineering an almost instant credibility boost. Soon other heavies, like Ralph Cicerone, president of the National Academy of Sciences, were also writing in favor of the concept. Their message: Geoengineering isn't, and shouldn't be, fringe science.

Cool. Psychodelic sunsets.

[Silent Acorns]

It is not relevant because …?
Climate is not a phenomenon that lends itself to chaotic behaviour, at least over the time scales we're talking about. You seem to be mixing up climate and weather. They're not interchangable.

The average will not oscillate, it will go up. What will oscillate are the extremes, and the seasonal weather patterns. Early springs will be nipped in the bud, preventing fruiting. The average will go up, but the maximums will be greater and more common and the minimums lower but more scarce.

This is not an example of chaotic climate. It's an example of more chaotic weather.

Again, the oscillation will not be in the average temperature, it will be in minimums, maximums, and the patterns of atmospheric and ocean currents. If you prefer the terms "instability" and "unpredictability" to "oscillations" I won't quibble.

I object to calling this "climate".

How many humans will survive maximum summer temperatures of > 130°F in the temperate zones? What will happen to the tropics when the equatorial rain forests become deserts, and the taiga is pushed to the arctic ocean? The richest growth of phytoplankton is where cold ocean currents well up and around the poles. When that bloom dies what will happen to the CO2 cycle? What will happen to the oxygen level of the atmosphere? There are species that might survive in a low O2 high CO2 environment but Homo sapiens isn't one of them.

These are extremely remote possabilities. It's irrespossible, and counter productive, to talk about these things as if they were any more than a theoretically possible, but highly unlikely, worst case scenario.

You’re not thinking about the effect that global warming will have on atmospheric chemistry.

I think you're exaggerating it out of all proportion.

Extinction is a real possibility, although admittedly not a certainty,

Not a "certainty"? You've got to be kidding me. Is that this all you're willing to grant? I'd consider you a nut-case if you put the probability of humans going extinct in the next 200 years due to global warming at any higher than 1 in a million.

(Unpredictability is inherent in chaotic systems like weather.)

There you go again, confusing weather with climate. Weather is inherently chaotic, but climate is not. Also, chaotic behaviour doesn't mean anything can happen, it just means that predictabilty is limited.

but those who live through the next centuries, if any do, will almost certainly not live well. And if they do live through it, they might not be recognizably human in any sense of the word.

I seriously think you should seek professional help. I don't mean to sound mean-spirited but the pessamism you're expressing is irrational (dare i say, pathalogical). It can't be healthy.

[Steve Weiss]

Climate is not a phenomenon that lends itself to chaotic behaviour, at least over the time scales we're talking about. You seem to be mixing up climate and weather. They're not interchangable.



This is not an example of chaotic climate. It's an example of more chaotic weather.



I object to calling this "climate".



These are extremely remote possabilities. It's irrespossible, and counter productive, to talk about these things as if they were any more than a theoretically possible, but highly unlikely, worst case scenario.



I think you're exaggerating it out of all proportion.



Not a "certainty"? You've got to be kidding me. Is that this all you're willing to grant? I'd consider you a nut-case if you put the probability of humans going extinct in the next 200 years due to global warming at any higher than 1 in a million.



There you go again, confusing weather with climate. Weather is inherently chaotic, but climate is not. Also, chaotic behaviour doesn't mean anything can happen, it just means that predictabilty is limited.



I seriously think you should seek professional help. I don't mean to sound mean-spirited but the pessamism you're expressing is irrational (dare i say, pathalogical). It can't be healthy.

Is this when they call you a denialist? That would be worse than being called late for supper. In fact, perhaps we are all in for the "last supper."

[blastula]

Don't believe politicians. They always have a reason to lie.

My belief for why the earth is warming is based on what I know of science and what climate scientists say. What is your belief based on?

Al Gore uses 20 times more energy than the national average.

True or not, Gore's household has nothing to do with whether or why the earth is warming.

The truth is that the earth has gone through this process before, it is not the first time earth experienced a global warming.

It is the first time the earth has gone through warming of this rate for the human population of this size, geographic distribution, and economic makeup.

Didn't I read somewhere Mars was also going through a global warming?

So? Earth and lots of other planets have warmed in the past without human activities. Is that supposed to prove humans aren't causing it now? Is that like, if yesterday you saw a patch of ground was wet because it rained, does that mean it's impossible for me to make the ground wet tomorrow by taking a piss?

At any given time, a planet's climate may be warming or cooling due to a combination of many factors. It just so happens right now in the year 2007, with the current combination of factors, the main known factor that could be pushing the rise in temperature is the rise in atmospheric greenhouse gases, and the rise in ghgs is known to be caused by burning of fossil fuels.