Legendary Climate Scientist Says Last Chance to Stop Global Warming

[AhmedEzz]

So what's your point exactly? The Earth was warmer and was more biodiverse than today...so what, we are talking about the effects of GW on humans, how it will affect countries, etc...

 

[Gokul43201]

First, being called a crackpot by bloggers on global warming fear mongering blogs is meaningless.

I don't know what blogs you are referring to. But to make it clear, let's just say I, personally, am calling him a crackpot and I'll be happy to defend that assertion in a different thread, if required.

Second, the information on the geologic time frames is absolutely correct.

I don't think anyone was disputing that.

Oh good grief, why didn't you say that earlier, I've been looking for accessible articles showing that what he posted was accurate. :grumpy: I've provided several of those.

Ok, I will shift gears, but my cooking show is about to begin. Here's one.

Species, Speciation and the Environment
Niles Eldredge

Paleontologist Dr. Niles Eldredge, is the Curator-in-Chief of the permanent exhibition “Hall of Biodiversity” at the American Museum of Natural History and adjunct professor at the City University of New York. He has devoted his career to examining evolutionary theory through the fossil record, publishing his views in more than 160 scientific articles, reviews, and books. Life in the Balance: Humanity and the Biodiversity Crisis is his most recent book.
http://www.gc.cuny.edu/directories/faculty/E.htm

Science & Nature Species Explosion
What happens when you mix evolution with climate change?

http://www.smithsonianmag.com/science-nature/species.html

As long as we stick to reputable sources, I have no problems. Incidentally, the first quotation is missing a link to the actual article.

So ignore him. Are the other articles Evo cited by crackpots?

I have not argued against the claim itself - only against the faulty argument that conducive temperatures in the past imply conducive temperatures today. That and the use of poor sources - I'm sure Evo didn't realize that Hieb is a dubious source.

Geologists, geographers, meteorologists? Evo is not saying that global warming is "good". She is merely citing what should be common knowledge: That the Earth has been a lot warmer than it is now and that life flourished when the Earth was warmer.

But that alone is hardly proof that continued warming today will cause life to flourish, which is why reliable sources and good citations are important.

 

[Evo]

I don't know what blogs you are referring to. But to make it clear, let's just say I, personally, am calling him a crackpot and I'll be happy to defend that assertion in a different thread, if required.

Why is he a crackpot concerning what I posted about climate in the Carboniferous Age? I made it clear when I posted it that that was all I was posting it for. To try to throw doubt on it when it is indeed correct? He's not a "dubious" source for that information, you yourself have agreed it's correct. So what's up with that?

 

[Gokul43201]

Why is he a crackpot concerning what I posted about climate in the Carboniferous Age? I made it clear when I posted it that that was all I was posting it for. To try to throw doubt on it when it is indeed correct? He's not a "dubious" source for that information, you yourself have agreed it's correct.

I have not "agreed it's correct". I only said that I had no intention of disputing the geological record presented there. I am neither qualified to dispute it personally, nor am I sufficiently well read to know the details. The one figure I looked at is drawn from sources that I find reputable and so I accept it's veracity, but there's a whole bunch of other stuff, including the conclusions, that is not sufficiently cited or is his personal judgement.

So what's up with that?

What's up is that the author of that site is a clearly biased and highly dubious source, so anything he writes is unreliable, except for those specific things that are directly drawn from more reliable sources.

 

[vanesch]

When are people going to take climate science back to science and out of the political propaganda sphere ?


We have observational data which suggests that the CO2 rise in the atmosphere correlates with human CO2 exhaust. I don't think there's much dispute about that.

We have much less sure observational data that suggests that global temperatures have *slightly* been rising. Recently however (satellite data on ocean temperatures) this is not clear at all.

We have the *hypothesis* that CO2 increase is going to act as a greenhouse gas. Simple radiation transport models ("all else equal") show us that a doubling of the CO2 (about beginning 2100) will give rise to a global increase in temperature of about 1 degree.

And then we have a LOT OF MODELS that add feedback to this radiation transport mechanism: increasing temperatures will do "other things" (so no more "all else equal"), like changed land usage (different vegetation, ice cover...), changed atmospheric content (water vapor, clouds,...), changing ocean currents, changing ocean composition, changing atmospheric composition and profiles, etc... and depending on the guesses one puts in these models, one can obtain positive feedback which then predicts temperature increases for a doubling of CO2 of up to 6 degrees.

However, these models don't work as of now yet in a scientific way, in that they make falsifiable predictions, those predictions are then observed, and so on. Indeed, recently they made different predictions of the ocean temperatures from those observed.

So all this indicates that: 1) it is indeed physically possible that a CO2 increase COULD give rise to serious temperature increases - not that it WILL be the case. But the possibility exists, so we should be careful.
2) we are not yet able to say with any certainty what will really happen. If you read the IPCC full reports, that's pretty clear. But in the summaries, doubts have made place for affirmative statements.

If that's not yet sufficiently murky, then people are going to model what will happen, GRANTED that temperature will rise with 6 degrees. There are of course some obvious, simple, things: sea level rise of a meter or so, ice melting, etc... Much more difficult is the prediction of what the biosphere will look like WITH HUMANITY 100 years from now. It is as if one tried to predict, in 1900, what earth, its biotopes etc... would look like in 2000, from extrapolations of evolutions at the end of the 19th century.

Now, all this can be an interesting intellectual exercise, but to go around the world fearmongering is the same as those preaching about the end of the world in the year 1000.

What climate science has shown is that the CO2 increase in the atmosphere can potentially give rise to a temperature increase, although how much has not yet been determined with any degree of certainty. That's about all we know. That should give rise to prudence, and to start thinking of how to get our CO2 exhaust down, just in case.

As to what value one puts to 1) future human generations, 2) biological life on Earth in the coming centuries 3) current human generations, that's not a scientific but a political and ideological discussion. Science should limit itself to telling people what it knows, what is plausible and possible and what is not clear yet.

 

[Integral]

I like Vanesch's post. He makes some very good points. What I have missed is any real discussion of the actual models used. I am sure they are at least as good as the models used by the weatherman on the local TV. Ok, let's hope they are much better! Even without direct knowledge of the models is it wise to reject their predictions just because I don't like the results? What is a stake here?

Yes, this is more a matter of a social and political decision then a scientific one. The Climatologists are saying that there is a reasonably good chance that GW will occur. Sure in the past the Earth was much warmer, What was the human population then? What was the state of civilization then? I am sure man could have lived just fine and civilization could have thrived then, that is not the problem.

The problem is the TRANSITION from our current climate patterns to perhaps a vastly different set of patterns. Since life on Earth is very robust I have no doubts that life will thrive under the potential new conditions, the question is can our civilization survive the changes? That is what we are gambling with the survival of our civilization, not life. How robust is our civilization? I do not think anyone can answer that question with anything other then idle speculation. I really seems that there is a LOT at stake, do we really want to continue on our current path when there exists a reasonable possibility as predicted that we are treading a dangerous path? Is it fear mongering to want changes to at least reduce our impact on the planet?

One has to ask what is the cost of being wrong?

If we act as if GW were real and reduced our consumption of fossil fuels, replacing them with "green" alternatives we could always burn the saved oil later, it would still be there waiting to be used.

On the other hand if we keep burning the oil as if it were an infinite energy source, clearly, since it is NOT an infinite energy source the day will come when the last drop is pumped out and burned, what then? Even if there is no such thing as GW if we have not prepared for the end of oil it will be an unmitigated disaster.

It seems to me that the ONLY prudent course is to act as if GW were real and imminent. Since to be wrong has no real ill effects. Being wrong on the other side, however, courts a major disaster for our way of life. Why gamble?

 

[Gokul43201]

When are people going to take climate science back to science and out of the political propaganda sphere ?We have observational data which suggests that the CO2 rise in the atmosphere correlates with human CO2 exhaust. I don't think there's much dispute about that.

We have much less sure observational data that suggests that global temperatures have *slightly* been rising. Recently however (satellite data on ocean temperatures) this is not clear at all.

I disagree with this, and I imagine, so would Andre. Over the last 30 years, there is an unarguable increase in the global anomaly, even if you look at only the least convincing dataset: the satellite data for lower tropospheric temperatures (MSU2LT).

I refer you to Andre's post with the linear regression fits for the different datasets: https://www.physicsforums.com/showpost.php?p=1677418&postcount=42

The satellite data shows an increase of about 1.4K/century from 1979 to 2007. This is a greater slope than for any other dataset over the last 100 years, which give numbers like 0.5K/century. The other datasets have slopes greater than 1.5K/century for the last 30 years.

We have the *hypothesis* that CO2 increase is going to act as a greenhouse gas. Simple radiation transport models ("all else equal") show us that a doubling of the CO2 (about beginning 2100) will give rise to a global increase in temperature of about 1 degree.

And then we have a LOT OF MODELS that add feedback to this radiation transport mechanism: increasing temperatures will do "other things" (so no more "all else equal"), like changed land usage (different vegetation, ice cover...), changed atmospheric content (water vapor, clouds,...), changing ocean currents, changing ocean composition, changing atmospheric composition and profiles, etc... and depending on the guesses one puts in these models, one can obtain positive feedback which then predicts temperature increases for a doubling of CO2 of up to 6 degrees.

However, these models don't work as of now yet in a scientific way, in that they make falsifiable predictions, those predictions are then observed, and so on.

I'm pretty sure the last IPCC reports made falsifiable predictions saying (approximately): if we maintain a Z(t) CO2 emission rate (t=time), we will see an increase in temperature over the next X years at a rate of about Y degrees per decade*. I think the early predictions for the scenarios of constant/decreased CO2 emissions may be somewhat off because back then, there was a somewhat poorer quantization of the amplitude of multi-decadal oscillations compared to what has come from papers in the last 1-2 years.

For instance, compare Schlesinger & Ramankutty, Nature 367, 723 - 726 (1994)
and Zhen-Shan & Xian, Meteorology and Atmospheric Physics, 95, 115–121 (2007).

Indeed, recently they made different predictions of the ocean temperatures from those observed.

Could you provide a reference? I hope you are not comparing the measured deep sea temperature decrease in sub-Arctic waters with the predicted surface water temperature increase.

* Edit: Found it.

For the next two decades a warming of about 0.2°C per decade is projected for a range of SRES emissions scenarios. Even if the concentrations of all GHGs and aerosols had been kept constant at year 2000 levels, a further warming of about 0.1°C per decade would be expected. Afterwards, temperature projections increasingly depend on specific emissions scenarios in the TAR mainly because the broader range of models now available suggests stronger climate-carbon cycle feedbacks. For the A2 scenario, for example, the climate-carbon cycle feedback increases the corresponding global average warming at 2100 by more than 1°C. Carbon feedbacks are discussed in Topic 2.3. {WGI 7.3, 10.5, SPM}

http://www.ipcc.ch/ipccreports/ar4-syr.htm

 

[vanesch]

Since life on Earth is very robust I have no doubts that life will thrive under the potential new conditions, the question is can our civilization survive the changes? That is what we are gambling with the survival of our civilization, not life. How robust is our civilization? I do not think anyone can answer that question with anything other then idle speculation. I really seems that there is a LOT at stake, do we really want to continue on our current path when there exists a reasonable possibility as predicted that we are treading a dangerous path? Is it fear mongering to want changes to at least reduce our impact on the planet?

I fully agree with you that given the state of knowledge of today, knowing that severe AGW is a possibility, one should err on the prudent side. But you make a very valid point: what is at stake is potentially our civilization and our way of life, NOT the biosphere, not "humanity", and not some or other biodiversity question.

So any "remedy" that would put "our way of life" more at stake than the potential danger that threatens it, would be a remedy worse than the illness. Fear is always a bad adviser. The exercise is to optimize somehow the quality of life now and in the relatively near future. We shouldn't take any drastic measures "to save the planet" that would endanger our way of life much more - but we should also not be reckless and not take into account the genuine risk for the near future. But all this should be thought over, and not decided in a kind of panic mood - which is the danger of the fear mongering.

Should we put work in switching away from fossil fuels ? Yes, and not only for the sake of "saving the planet". But should we do it in a drastic way, that puts whole populations in peril ? No, certainly not, that would be exactly the "remedy" that's worse than the "illness".

 

[Andre]

There is a tiny technical problem though; where is that global warming?

https://www.physicsforums.com/showthread.php?t=239131

 

[Integral]

There is a tiny technical problem though; where is that global warming?

https://www.physicsforums.com/showthread.php?t=239131

What difference does it make? The measures we need to take to control greenhouse gases are the same ones we need to take to free ourselves from the oil addiction. Your denial is counter productive, it serves no good purpose other then to put our civilization at risk. Let us take prudent measures to reduce our dependence on fossil fuels NOW.

I really cannot see the point of your arguments.

 

[Integral]

I fully agree with you that given the state of knowledge of today, knowing that severe AGW is a possibility, one should err on the prudent side. But you make a very valid point: what is at stake is potentially our civilization and our way of life, NOT the biosphere, not "humanity", and not some or other biodiversity question.

So any "remedy" that would put "our way of life" more at stake than the potential danger that threatens it, would be a remedy worse than the illness. Fear is always a bad adviser. The exercise is to optimize somehow the quality of life now and in the relatively near future. We shouldn't take any drastic measures "to save the planet" that would endanger our way of life much more - but we should also not be reckless and not take into account the genuine risk for the near future. But all this should be thought over, and not decided in a kind of panic mood - which is the danger of the fear mongering.

Should we put work in switching away from fossil fuels ? Yes, and not only for the sake of "saving the planet". But should we do it in a drastic way, that puts whole populations in peril ? No, certainly not, that would be exactly the "remedy" that's worse than the "illness".

Unfortunately I have little or no confidence in the politicians of the US or any other country. How can we find the correct path to survival when there are so many questions and so few solid answers?

 

[vanesch]

I disagree with this, and I imagine, so would Andre. Over the last 30 years, there is an unarguable increase in the global anomaly, even if you look at only the least convincing dataset: the satellite data for lower tropospheric temperatures (MSU2LT).

I refer you to Andre's post with the linear regression fits for the different datasets: https://www.physicsforums.com/showpost.php?p=1677418&postcount=42

The satellite data shows an increase of about 1.4K/century from 1979 to 2007. This is a greater slope than for any other dataset over the last 100 years, which give numbers like 0.5K/century. The other datasets have slopes greater than 1.5K/century for the last 30 years.

Ok, now let's take the numbers from that post:

Period:...1979-2007...1998-2007
GHCN:...0.193...0.199
NOAA:...0.170...0.127
HADCRUT:..0.170...0.041
MSU2LT...0.142...0.057

If I understand well, the numbers are degrees per decade for 4 different estimators of global temperature. Now, what do we see ? 3 out of 4 of them have a LOWER value of the set 1998-2007 than for the set 1979-2007, which means that the slope is DECREASING. If the CO2+feedback+whatever panic scheme were right, then the slope should be INCREASING, as in the mean time, the CO2 level has been increasing, and all the positive feedback had more time to act.

Simple maths: if between x1 and x3, the slope is s1, and between x2 and x3, the slope is s2, then we have: total increase is d3 = (x3-x1) x s1 ; increase between x2 and x3 is d2 = (x3-x2) x s2, so the increase between x1 and x2 is d1 = d3 - d2 = (x3-x1) x s1 - (x3-x2) x s2
or the slope between x1 and x2 is: s3 = [ (x3-x1) x s1 - (x3-x2) x s2 ] / (x2 - x1).

If you do that naively to the numbers above, then we find as slopes between 1979 and 1998:

GHCN:...0.190
NOAA:...0.190
HADCRUT:..0.231
MSU2LT...0.182

Now, I know that we are talking about regression coefficients with a lot of noise and so on, but it seems clear from these data that the temperature increase between 1979 and 1998 was stronger than between 1998 and 2007. So it's getting hotter less fast between 1998 and 2007 than between 1979 and 1998. That's absolutely not in agreement with "more CO2, more warming".

I'm pretty sure the last IPCC reports made falsifiable predictions saying (approximately): if we maintain a Z(t) CO2 emission rate (t=time), we will see an increase in temperature over the next X years at a rate of about Y degrees per decade*. I think the early predictions for the scenarios of constant/decreased CO2 emissions may be somewhat off because back then, there was a somewhat poorer quantization of the amplitude of multi-decadal oscillations compared to what has come from papers in the last 1-2 years.

Was there a clear prediction of a *slowing down* of the increase of temperature between 1998 and 2007 BEFORE these data were available ? In other words, a *real* prediction ?

Because if not, then the increase between 1979 and 1998 which was then enhanced by any kind of oscillation might otherwise have been taken as "calibration" and justification for the "flat" response.

Could you provide a reference? I hope you are not comparing the measured deep sea temperature decrease in sub-Arctic waters with the predicted surface water temperature increase.

Well, have a look at Andre's post: https://www.physicsforums.com/showthread.php?t=239131
and then there is http://data.giss.nasa.gov/gistemp/graphs/Fig.A4.pdf

EDIT: just not to be misunderstood, I'm NOT saying that AGW is not a potential issue. And I DO think that there are many reasons to get away from fossil fuels. But I'm against all this irrational fear mongering. It can only lead to irrational decisions, and a lot of unnecessary problems. I'm also claiming that these things are far less understood than the fear mongerers (and also the negationists) claim. The real answer is that we really don't know what's going to happen 100 years from now, and that there is a potential for warming.

 

[D H]

What difference does it make? The measures we need to take to control greenhouse gases are the same ones we need to take to free ourselves from the oil addiction.

I disagree. While freeing ourselves from the oil addiction may reduce emissions somewhat, I doubt it does so to the extent some claim we need to reduce emissions. We still have a lot of coal, after all. If we switch the majority of the vehicles on the road from gasoline-powered internal combustion vehicles to coal-powered battery driven vehicles, we will have taken a big step to reducing our oil dependence but a only small step to reducing our carbon footprint.

 

[Gokul43201]

Sure in the past the Earth was much warmer, What was the human population then? What was the state of civilization then?

Over the last 5 years, we have been about 0.5C warmer than the temperatures during the Medieval Warm Period[1,2] according to most published sources. Even the most skeptical estimates (those which eliminate tree-ring data) say that we now at similar temperatures to the MWP[3]. Before that, the last time we had temperatures that were comparable or slightly higher than today's temperatures, was about 125,000 years ago[4]. The last time that the Earth was significantly warmer was most likely several million years ago[5].

Civilization began less than 8,000 years ago. The really warm temperatures were probably during the time of australopithecus[6].[1] A. Moberg et al, Nature, 443 613-617 (2005)
[2] J.H. Oerlemans, Science, 308 675-677 (2005)
[3] C. Loehle, Energy & Environment, 18 1049-1058 (2007)
[4] Petit et al, Nature, 399 429-436 (1999)
[5] Paleomap Project
[6] http://www.wsu.edu/gened/learn-modules/top_longfor/timeline/timeline.html

 

[Gokul43201]

Ok, now let's take the numbers from that post:
If I understand well, the numbers are degrees per decade for 4 different estimators of global temperature. Now, what do we see ? 3 out of 4 of them have a LOWER value of the set 1998-2007 than for the set 1979-2007, which means that the slope is DECREASING.

Actually, you can't really say that. When you look at the 10-year data, the error bars in the slopes (which are not included in that table) become larger than the change in the slope, so the 10-year slopes are mostly meaningless (i.e., 9-year and 11-year slopes are different from the 10-year slopes by over 50%). This is why I compared the 30-year trend with the 100-year trend (errors bars are smaller and a comparison becomes meaningful).

These large error bars in 10-year data are due to the small size of the dataset, but also importantly, due to the choice of end-points. 1998 experienced an anomalously high temperature and is a terrible choice of endpoint. Look at my follow-up post in that other thread for more on this.

Secondly, even if the "slope" is currently decreasing, which I suspect it is, we come to this:

If I understand well, the numbers are degrees per decade for 4 different estimators of global temperature. Now, what do we see ? 3 out of 4 of them have a LOWER value of the set 1998-2007 than for the set 1979-2007, which means that the slope is DECREASING. If the CO2+feedback+whatever panic scheme were right, then the slope should be INCREASING, as in the mean time, the CO2 level has been increasing, and all the positive feedback had more time to act.

Again, I must say I don't think so. The two biggest features observed in global temperatures over the last 130 years are an upward trend that correlates well with CO2 levels and a multi-decadal (50-70 year) oscillation (origin not well-understood by me). If temperature increases from GHG forcings (+some other things) is sufficiently positive and nearly linear in time, then the slope during an upswing of the multi-decadal oscillation will be greater than that during a downswing. Since we are currently starting on a downswing, it would be reasonable to see a decrease in the overall slope for the period 2000-2020 compared to the period 1980-2000. This is the same reason that the slope during the 1940-1975 period was much smaller than that during the 1915-1940 period.

Again, I refer you to the two citations in my earlier post (the one you quoted).

 

[vanesch]

Actually, you can't really say that. When you look at the 10-year data, the error bars in the slopes (which are not included in that table) become larger than the change in the slope, so the 10-year slopes are mostly meaningless (i.e., 9-year and 11-year slopes are different from the 10-year slopes by over 50%).

I know. But it works in 2 ways: if we can't say anything over less than 30 years, then we should wait 30 years before looking at predictions, and not start shouting right now that the data prove (or disprove) this or that model, and hence that the world is FOR SURE facing this or that tragedy or on the other hand, that this or that prediction was wrong and hence that all that is BS. As the "experiment" takes at least 30 years, you cannot say ANYTHING right now with any affirmative certainty, that was my point.
The possibility exists. We are not sure. That's the real scientific statement right now.

But people don't like uncertainty. They don't like to say that they don't really know (but just have some suggestive evidence) ; they don't like to hear it and to deal with the uncertainty in the decision making. However, that's how things really are.

Imagine it was a certainty that if we go on this way, then in 100 years, Earth would be 30 degrees warmer. We would for sure almost all die. So, what do we do ? Take still a few decades of good life and then plan some kind of painless collective suicide ? Bomb all coal plants, bomb all petrol infrastructure right away ? Try to kill humanity immediately, so that the giant ants after us will still have a chance ?

Imagine that it was sure that if we go on this way, Earth would warm with, say, 7 degrees. What do we do now ? Still take a few decades of good life and to hell with future generations ? Or sacrifice half of the current world population and dump it in misery by stopping one way or another (with a global war, I presume) the consumption of oil and coal ? Or try to switch slowly to less CO2 producing technologies ?

Imagine that it was sure that if we go on this way, Earth would warm, by say, 1 degree. What do we do now ? I'd say: solve our current problems and try to enjoy life !

Imagine that it was sure that if we go on this way, Earth would enter a new ice age ? What do we do now ? Produce a lot of CO2 more than we are currently doing ?

Point is, we aren't sure. So we have to weight in the uncertainties with the risks for the future and the well-being of today.

 

[Gokul43201]

I know. But it works in 2 ways: if we can't say anything over less than 30 years, then we should wait 30 years before looking at predictions, and not start shouting right now that the data prove (or disprove) this or that model, and hence that the world is FOR SURE facing this or that tragedy or on the other hand, that this or that prediction was wrong and hence that all that is BS. As the "experiment" takes at least 30 years, you cannot say ANYTHING right now with any affirmative certainty, that was my point.

I don't think I've ever said that we know anything with a great certainty right now. Even by my earlier post on the IPCC prediction, we must wait at least about 20-years for them to gain scientific credibility. Given that multi-decadal oscillations are a big factor, I would typically (for a purely scientific purpose) like to wait for at least a few more oscillations to match predictions, and that would mean waiting a couple centuries.

I will be most glad to wait, with you, for the data to match the calculations. Maybe on some warm January evening, when we're old men, we can share a pitcher of beer, as we look at the numbers together in a seaside Parisian cafe, the warm waters of the English Channel swirling by our feet. We could even make jokes about the giant ants living on the Eiffel Tower.

 

[WheelsRCool]

Me personally, I am highly skeptical of global warming, but even if it is true, I have no problem acknowledging this and working to try and handle it or curb it some, what I am staunchly against is using global warming as an excuse to greatly increase the power of the state in our lives (and in the minds of the extremists, bring down capitalism and Western civilization).

I am against things like heavy carbon taxes, carbon cap-and-trade, greatly increasing regulation, controlling people's thermostats (no joking, California tried to pass legislation where the State could adjust people's temperatures in their homes), etc...

 

[Andre]

Given that multi-decadal oscillations are a big factor, I would typically (for a purely scientific purpose) like to wait for at least a few more oscillations to match predictions, and that would mean waiting a couple centuries.

Disregadring tongue in cheek but we might be able to settle things sooner, if we would manage to keep it purely scientific, doing the homework, banning politics, passion and personal agenda's.

Now, firstly, the actual temperature data do not suggest a high CO2 sensitivity as posted earlier.

Secondly, radiation models like MODTRAN cannot produce a high CO2 sensitivity in the IPCC range of thinking, nor can the theory, then where is that high sensitivity with the tipping point stories coming from?

The answer is paleo climatology, told about, highly detailed, by Spencer Weart here

http://www.aip.org/history/climate/
http://www.aip.org/history/climate/rapid.htm
etc

The focal point here is the water isotope variation (dD and d18O), which is interpreted as temperatures. The wild oscillations suggest things like ten degrees within a decade. So with in mind, the search is for the unkown climate factors like positive feedback.

But modern hydrography dealing with water isotopes proves to be very complex and the isotope interpretation is really only one dimension. There are more possibilities. Moreover, when really zooming in on the dirty details, things do not add up at all. There are other interpretations possible, working around those spectacular temperature changes. Without those, there is no case for dramatic tipping points type of global warming. But that's only when we manage to keep things scientific and run suppositions until it all matches, we don't need to wait for the non existing tipping points.

 

[vanesch]

I don't think I've ever said that we know anything with a great certainty right now. Even by my earlier post on the IPCC prediction, we must wait at least about 20-years for them to gain scientific credibility. Given that multi-decadal oscillations are a big factor, I would typically (for a purely scientific purpose) like to wait for at least a few more oscillations to match predictions, and that would mean waiting a couple centuries.

I will be most glad to wait, with you, for the data to match the calculations. Maybe on some warm January evening, when we're old men, we can share a pitcher of beer, as we look at the numbers together in a seaside Parisian cafe, the warm waters of the English Channel swirling by our feet. We could even make jokes about the giant ants living on the Eiffel Tower.

Now, THAT would be a great way to end my life ! I sign for it, immediately !

 

[DrClapeyron]

As long as people continue to imply the disasterous consequences of global warming, it will remain a political issue.

 

[Gokul43201]

Absolutely. I've noticed that even though the price of gas has doubled over the last year, there are as many cars on the road as there has ever been. The majority of people aren't changing their habits.

They actually are starting to change now...though it may be a while before we see anything drastic.

Americans drove 22 billion fewer miles from November through April than during the same period in 2006-07, the biggest such drop since the Iranian revolution led to gasoline supply shortages in 1979-80.

The numbers released Wednesday may reflect more than a temporary attitude change in consumers toward high gas prices, Transportation Secretary Mary Peters said. Previously, she said, "people might change their pattern for a short period of time, but it almost always bounced back very quickly. We're not seeing that now."

http://www.usatoday.com/news/nation/2008-06-19-drivingless_N.htm?loc=interstitialskip

 

[edward]

Its ironic that the intelligence community and national Security agencies have been studying the effects of GW on national security for some time now.

http://www.abcnews.go.com/Technology/Story?id=5242639&page=2

 

[Andre]

What difference does it make? The measures we need to take to control greenhouse gases are the same ones we need to take to free ourselves from the oil addiction. Your denial is counter productive; it serves no good purpose other then to put our civilization at risk. Let us take prudent measures to reduce our dependence on fossil fuels NOW.

I really cannot see the point of your arguments.

I missed this one, but it requires addressing once more, because this is the core business and I could not disagree more. Why pointing out the flaws of the global warming issues, when humanity needs to convert to a sustainable energy system anyway? And reducing carbon emission would have the same effect, wouldn't it?

Suppose that the weather forecaster talks about nice dry warm weather in the next days but instead a cold wet spell arrives, he would be a bit embarrassed. But if it turns out that the forecaster was using bad science or perhaps even spun the data to arrive at that desired conclusion, then nobody would believe forecasters anymore and the branch would be down out.

Point is that science appears to be misused for politics and commits high treason against its main objective, to find the truth. If global warming is not the truth, it should be said in time before reality overtakes, in order to save a bit of its trustworthiness and its right to exist.

How long can you pretend global warming when the messages of cold spells wordwide, get more and more frequent? And if this branch of science doesn't purge itself in time, don't count on getting it a second chance.

From the practical point of view, limiting CO2 in the atmosphere, is not nearly the same as transiting into a sustainable energy society. The former would call for all kind of CO2 removal techniques for climate purposes, which would be a waste of time and assets, if it would not change anything. Also, it would obstruct the use of other carbon fuels reserves like oceanic methane hydrate, which would buy time to reach the sustainable society.

Trying to trick humanity into a necessary right direction for the wrongs reasons, will bounce hard:

A: "Trust me, nuclear power is now safe and adequate to solve all energy issues".
B: "yeah right, Go fool somebody else, look at the global warming debacle. I'm not buying anything from you anymore".

And to add my personal agenda: the suppositions about paleo climate during the ice ages, leading to the climate scare, are highly contradictory and cannot be right which obstructs finding out what really happened.