Moderated Global Warming Discussion

[BenBurch]

Truethat; Those disturbances are deviations from the norm. We are MOVING THE NORM.

That is the essential difference and the crux of the problem.

 

[truethat]

What norm? The planet has a norm? The planet is a mess when it comes to climate? We're just not used to it because we've only been here a blip. But the planet always has temperature shifts etc. No? Not trying to be obtuse. I can see people here are well versed as it is. But one volcanic eruption could lower the temperature of the planet for decades. Why is it we think we are such a threat at the moment. We are learning how to create cleaner fuels etc It will take us a few decades to get there but we will.

So why this huge panic? Even if we did find a solution right this very second, and implement it right this very second. It wouldn't have an impact for decades? Right?

 

[lomiller]

Anyone who cares can examine that sequence of posts and verify that I quoted and was referring to the following statement of yours:

This sequence of posts go back much farther than post 6832.

We are discussing this because you disliked my opinion on the paper by Fildes and Kourentzes paper that compared DePreSys to statistical models of their own devising. I felt that there was little value to such comparisons and that because they were publishing in a journal unrelated to climate or physical modeling they were at risk for misunderstanding the physical modeling element of the paper.

Stating the conclusions of the DePreSys team changes nothing about this, and the nature of what they were doing is something I had been discussing for a week prior to your post.


Going back to post 6685, you said

On the other hand, showing that you can is a non-trivial result that I personally find interesting.

The main results of the paper are:

The problem is that the interesting parts of the results you listed, the decadal predictions themselves, didn’t come from Fildes and Kourentzes they come from the work DePreSys was doing, something I pointed out explicitly in post 6804:

The paper you are supporting does not add to or contribute to this finding in any meaningful way. The DePreSys team already did suitable skill calculations.

Even before that, however, discussed the value and nature of decadal predictions as far back as post 6731

Your suddenly concluding it was DePreSys making contributions to the science is a back peddle because you started off by claiming it was Fildes and Kourentzes who made this contribution and I had been discussing the pro’s and cons of these decadal predictions for a week already before you suddenly concluded it was the original predictions that were worth discussing.

 

[BenBurch]

Truehtat,

It gets worse every second.

And the consequences are dire.

Yes, the planet has a norm described by the calculations of the greenhouse effect based on the work of Arrhenius and others.

When they calculated what the temperature of the Earth ought to be based on physics, the "black body" calculation, they found that the planet should be an iceball.

So why isn't it?

The tiny amount of CO2 we have in the atmosphere changes the hysteresis time for energy entering the system and so increases temperature.

Climate is therefore very sensitive to changes in CO2.

We are making HUGE changes in the amount of CO2, and so we are raising the "natural" temperature of the planet around which perturbations dance.

 

[truethat]

double post

 

[truethat]

Right but plant a bazillion trees and problem solved. I'm not trying to make light of it but the earth is not going to turn into an iceball ala The Day After Tomorrow.

It's hype. We are moving forward to solve problems. Dire to me means, nothing we can do about it and right now we're out of time.

That's simply not the case.

When we talk about a patient having dire consequences we mean if they don't change it they could die. But the earth is not going to die. (The people are....thank you George Carlin) If we want a better environment for people we need to plant more trees and stop stripping rainforests etc etc and move towards cleaner fuels.

We're doing that. So why is it dire?

 

[jimbob]

Right but plant a bazillion trees and problem solved. I'm not trying to make light of it but the earth is not going to turn into an iceball ala The Day After Tomorrow.

It's hype. We are moving forward to solve problems. Dire to me means, nothing we can do about it and right now we're out of time.

That's simply not the case.

When we talk about a patient having dire consequences we mean if they don't change it they could die. But the earth is not going to die. (The people are....thank you George Carlin) If we want a better environment for people we need to plant more trees and stop stripping rainforests etc etc and move towards cleaner fuels.

We're doing that. So why is it dire?

We are not doing enough, soon enough.

Also, a slight shift in weather patterns in (say) the Middle East means that some cities or even countries will be in the wrong place, and they can't move because of international boundaries, so expect increased conflict.


ETA: At the moment, human activities are increasing atmospheric CO₂ by about 1% per year, which is pretty significant.

The 2010 Icelandic volcanic eruption is generally assumed to have been Carbon-negative as the suppression of aviation more than compensated for the geological emission of CO₂

 

[truethat]

Right but where's this direness. The volcano had an impact as well. We're doing things, there isn't a person out there who doesn't know about it. We're being mindful and we're working towards slowing it down.

But again please explain to me how Krakatoa's eruption had less of an impact on the CO2 in the planet's atmosphere than planes flying do. That would be helpful, that's where I'm confused.

You just wrote the eruption of the volcano had less of an impact than airplanes flying for the amount of time. This just seems like an impossibility to me. Please cite and clarify.

 

[lomiller]

What norm? The planet has a norm?

The Earth’s climate has an attractor, around which our weather will be distributed. This is being altered by human activity.

But the planet always has temperature shifts etc. No? Not trying to be obtuse. I can see people here are well versed as it is.

The current and expected rate of warming is about 2 degrees per 100 years. Warming coming out of a glaciation is on the order of 1 degree per 1000 years. At current rates, the earth will have warmed 3 degress over 200 years by the end of the century. Warming that ended the last glaciations and completely re-shaped the earth was ~6 degrees over 5000 years.

But one volcanic eruption could lower the temperature of the planet for decades.

Very big eruptions can create signals present for decades. This is different than creating measurable cooling for decades. Even the Mt Toba eruption 75000 years ago, the largest in at least 15 million, was felt for only a decade or so.

 

[truethat]

That's not what they say about Krakatoa. They said it cooled the planet for decades and cooled it by 22 degrees. So if that can happen in one week and the planet isn't freezing solid why do you think raising the temperature 1 degree in a decade would do worse.

Like I said not trying to be contrary here, it just seems like a who heck of a lot of overreacting.

 

[W.D.Clinger]

amusing history of the Fildes and Kourentzes paper

From my review of the Fildes and Kourentzes paper, snipping brown text:

The main results of the paper are:

• For forecasting 1-4 years ahead, predictions based upon physical models (DePreSys) outperform all of the purely statistical algorithms. (snip)
• For forecasting 10 years ahead, predictions based upon physical models (DePreSys) outperform a majority of the purely statistical algorithms. (snip) In particular, predictions based upon physical models outperform the random walk model by a large margin. (snip)
• The best of the purely statistical predictors predicts the same annual increase in average temperature as the IPCC AR4 report's scenario A2 (which essentially assumes continuation of current policies). (snip)

As noted in my review, however, I regard much of the paper as badly written. The paper's abstract and conclusions downplay the above results, and could give a careless reader the false impression that purely statistical models performed about as well as DePreSys.

I now know what happened. In an earlier version of the paper, which was likely to have been their original submission to the International Journal of Forecasting, Fildes and Kourentzes thought they had shown that DePreSys performs worse than random walks and other purely statistical methods.

Comparing the final paragraphs of section 3.1.1, we see that

The forecasts from DePreSys performed poorly.

turned into

The forecasts from DePreSys outperformed the statistical models for the shorter hold-out sample period, thus failing to support the view that the GCMs are unable to capture short-term fluctuations. (We note that the moving average process applied by Smith et al. improves the accuracy further.)

That correction was made necessary by a very large downward correction to the error reported for DePreSys in Table 1. The acknowledgements explain:

Critically, a referee identified an error in the data we used initially.

I'm left wondering whether Fildes and Kourentzes would have written the paper at all if they had known it would end up countering the meme being promoted by so many denialist blogs.

In any case, I salute the journal's peer review process. That reviewer caught a whopper.

 

[truethat]

That's not what they say about Krakatoa. They said it cooled the planet for decades and cooled it by 22 degrees. So if that can happen in one week and the planet isn't freezing solid why do you think raising the temperature 1 degree in a decade would do worse.

Like I said not trying to be contrary here, it just seems like a who heck of a lot of overreacting.

 

[lomiller]

But again please explain to me how Krakatoa's eruption had less of an impact on the CO2 in the planet's atmosphere than planes flying do. That would be helpful, that's where I'm confused..

Humans burning fossil fuels put orders of magnitude more CO2 into the atmosphere than volcanoes.
http://www.agu.org/pubs/pdf/2011EO240001.pdf

This just seems like an impossibility to me. Please cite and clarify.

Incredulity isn’t an argument.

 

[truethat]

No just explain to me how it makes sense to you. I'm fully willing to be wrong. It just doesn't make any sense to me. How can a volcano that was as devastating as Krakatoa which is in our era of human history, be less damaging that all the fossil fuels being used to fly airplanes.

LONDON — Sea levels would have risen higher and ocean temperatures would have been warmer in the 20th century if the Krakatoa volcano in Indonesia had not erupted in 1883, scientists said on Wednesday.

The impact of the eruption that spewed molten rock and sulfate aerosols into the atmosphere was felt for decades — much longer than previously thought.

"It appears as though with a very large eruption the effect can last for many decades and possibly as long as a century," said Peter Gleckler, a climatologist at the Lawrence Livermore National Laboratory in California.


redOrbit (http://s.tt/16nnv)

You are all saying it's not true but this is what every report on the this volcanic eruption that I have ever seen has said.

I mean it seems to me if the temperature is lowered by 20 degrees and then it starts creeping back up again that would be what I would think was a logical conclusion.

Don't get pissy with me because I'm not debating this I just don't see how you can say that airplanes not flying for a week has more of an impact than a volcanic eruption that lowered the temperature of the planet by 20 degrees for decades?

Not to mention wiping out millions of plants and trees thereby increasing the CO2 level.

Is it connected ONLY to the CO2 and the trees or something?

 

[lomiller]

As noted in my review, however, I regard much of the paper as badly written. The paper's abstract and conclusions downplay the above results, and could give a careless reader the false impression that purely statistical models performed about as well as DePreSys.

Ok I’ll leave this alone for now then except to add the bit below.

I'm left wondering whether Fildes and Kourentzes would have written the paper at all if they had known it would end up countering the meme being promoted by so many denialist blogs.

Probably not given that the journal it appeared in is also run by a documented climate denier. (as I believe Ben indicated in a post)

My position all along has been that there are sufficient red flags to not give this paper too much credence without this knowledge. You see this on other fields of course, but it’s common in climate denial as well. What happens is someone, usually with little climate science background, writes a biased/bad paper and then searches around for someone to publish it. They get rejected by editors with experience in the field but eventually find one in a quasi-related filed that isn’t up on current literature and is willing to publish it.

The typical characteristics of such papers are:
Little previous experience in the filed
Published in a minor or quasi-related filed
Is on the fringes of current science in the filed or contradicts the bulk of the literature in the field.

To me, regardless of their conclusion this paper seemed to have the hall marks of this type of publication shopping so

 

[lomiller]

I mean it seems to me if the temperature is lowered by 20 degrees and then it starts creeping back up again that would be what I would think was a logical conclusion.

Where are you getting the 20 degrees from?

Estimates for the temperature dope in the year following the eruption are much lower than that. Even estimates for the years following the Toba eruption, which was MUCH larger, are smaller than that. BTW the cooling comes from dust and aerosols not CO2 which lastes much longer.

 

[truethat]

Ah I see, so the cooling comes from the ash blocking the sun and you are saying the CO2 issue is worse. Ok that makes sense. But take Mt St Helens or any other recent eruptions or even Tsunamis etc. The damage to the trees would definitely have an impact on the CO2 levels. So while the pollution in the air is problematic, of course, no debate, the solution is to plant more trees. And trees need time to grow.

 

[bobwtfomg]

Right but plant a bazillion trees and problem solved. I'm not trying to make light of it but the earth is not going to turn into an iceball ala The Day After Tomorrow.

It's hype. We are moving forward to solve problems. Dire to me means, nothing we can do about it and right now we're out of time.

That's simply not the case.

When we talk about a patient having dire consequences we mean if they don't change it they could die. But the earth is not going to die. (The people are....thank you George Carlin) If we want a better environment for people we need to plant more trees and stop stripping rainforests etc etc and move towards cleaner fuels.

We're doing that. So why is it dire?

Yes as jimbob said we're not doing enough soon enough
from an earlier post of mine

Too late for 2 degrees?
report from international buisiness consultants PriceWaterhouseCooper
http://www.pwc.com/gx/en/sustainability/publications/low-carbon-economy-index/index.jhtml

The 2011 rate of improvement in carbon intensity was 0.8%. Even doubling our rate of decarbonisation, would still lead to emissions consistent with six degrees of warming. To give ourselves a more than 50% chance of avoiding two degrees will require a six-fold improvement in our rate of decarbonisation.

Yes it's not about day after tomorrow doomsday scenarios or the earth dying it's about how humanity is going to adapt to a warmer world. Adapting to a 2 degree rise will be tough, 6 degrees doesn't bear thinking about. http://channel.nationalgeographic.com/channel/videos/six-degrees-could-change-the-world/

here's a good intro to climate science, though a little out of date , it has CO2 at 383ppm and now it's 392.
http://www.windows2universe.org/earth/climate/greenhouse_effect_gases.html

 

[bit_pattern]

, the solution is to plant more trees. And trees need time to grow.

No. The solution is to figure out how to reduce emissions while maintaining economic growth. Trees take too much time to grow to avert a disaster, we need to act much faster than that. And I'm not sure you appreciate the scope of just how many trees we'd need to make a dent in the problem.

 

[bit_pattern]

Truethat - please read:

http://theconversation.edu.au/our-e...real-how-were-geo-engineering-the-planet-1544