Does anyone still believe in Global Warming? Have we all finally concluded that it was a hoax?

Below normal all week for Iqaluit, snowing all week.

Apply same logic here.

Athletics Illustrated wrote:

Below normal all week for Iqaluit, snowing all week.

Apply same logic here.

I have this toenail fungus that stubbornly refuses to go away. Had it for over a year.

Ditto on the whole logic thing.

super hot guy wrote:

High of 86 forecast for Denver today. That will smash the previous high of 82 set in 2011. Is it just coincidence that the two hottest days ever are within the last 3 years? Global warming is REAL!

EOT

The 2 hottest days ever or 2 hottest days "on record?"

Conundrum wrote:What you posted, "In the world of Bayesian probability, which is to my mind the only valid one, this translates to a 75-80% probability that AGW is true."

That was enough to qualify you. Now I didn't say you would be a starter on "Team Reality" but I do try to give all the guys sitting on the bench some encouragement.

Don't twist my words too far..."translates to a 75-80% probability that AGW is true...." also implies a 20-25% chance it is false. 20-25% probability is way more than reasonable doubt.

Plus I can think of several cases where a stronger consensus was proven wrong... Y2K, WMD in Iraq, the sun revolving around the earth... Of course there are many, many other cases where the strong majority opinion was proven right, and that does factor into my thinkin

I've done some doodling with the global temperature anomaly data. Here are all the data, showing annual and decadally smoothed data:

I've spent a lot of time looking at these data and thinking about patterns. I decided to see how well I could deconstruct them. Here is a quadratic trend line over the same data:

If we subtract that broad trend, we get the following:

This has some periodicity at several time scales, but looking at the decadal scale we can infer a broad periodicity of about 64 years with amplitude +/- 0.15:

We can take 5th and 95th percentile limits to capture (nearly all of) the shorter period variability and add them to the graph:

And finally, if we add the ~ 64 year periodic function with its confidence limits to the initial overall trend, we get the following:

This shows us hitting ~ +1.8C at 2100. However, this assumes the continued upward trend inferred from the first best fit. I think it's rather more likely that trend reflects some longer period variability and there is a natural phenomenon (or combination thereof) that will have that trend reverse itself on some kind of century scale.

Of course the other hypothesis is that trend is largely driven by atmospheric, anthropogenically generated carbon, in which case it's a runaway train...

hmmmmmm? wrote:

This has some periodicity at several time scales, but looking at the decadal scale we can infer a broad periodicity of about 64 years with amplitude +/- 0.15 . . .

The ~64 year cycle is generally attributed to the Atlantic Multidecadal Oscillation (

). It is, of course, chancy to apply spectral techniques to a small number of cycles and declare periodicity.

hmmmmmm? wrote:

This shows us hitting ~ +1.8C at 2100. However, this assumes the continued upward trend inferred from the first best fit. I think it's rather more likely that trend reflects some longer period variability and there is a natural phenomenon (or combination thereof) that will have that trend reverse itself on some kind of century scale.

Of course the other hypothesis is that trend is largely driven by atmospheric, anthropogenically generated carbon, in which case it's a runaway train...

While everyone is entitled to their opinion, I find it strange when someone favors an unidentified and unquantified "natural phenomenon" over a hypothesis which at least has some clear physical basis and which is broadly corroborated by multiple lines of evidence.

Citizen Runner wrote:While everyone is entitled to their opinion, I find it strange when someone favors an unidentified and unquantified "natural phenomenon" over a hypothesis which at least has some clear physical basis and which is broadly corroborated by multiple lines of evidence.

The ice core proxy "data" and other geological records show oscillations at much to much, much longer return periods, and the actual recorded data show oscillations at shorter time scales. There will also be natural oscillations at all time scales between what we can infer from proxy information and what we know from real information.

Whether the crude trend I extracted represents a clear anthropogenic signal rather than an arm of a natural fluctuation, who can say? I guess I think the chances are 75-80% it's the former and 20-25% it's the latter...

super hot guy wrote:

High of 86 forecast for Denver today. That will smash the previous high of 82 set in 2011. Is it just coincidence that the two hottest days ever are within the last 3 years? Global warming is REAL!

EOT

Hot in Denver, huh?

Well watch out - the snow in Siberia is piling up, and if it keeps coming, people in New York may have to bundle up this winter.

There’s a theory that the amount of snow covering Eurasia in October is an indication of how much icy air will sweep down from the Arctic in December and January, pouring over parts of North America, Europe and East Asia.

Last year, the snow level across Eurasia was the fourth highest for the month in records going back to 1967.

In January, frigid temperatures dubbed “the polar vortex” slid out of the Arctic to freeze large portions of the U.S.

It was a pattern that repeated itself during the Northern Hemisphere winter and helped make the first three months of this year the coldest in the 48 contiguous states since 1985, according to the National Climatic Data Center in Asheville, North Carolina.

With the snow now piling up across Eurasia, will this winter be a grim reminder of last years?

Sally V wrote:

I am pretty sure I am smarter than most climate scientists. They have a horrible track record.

Yes, you obviously know more about climate science that the entire worldwide community that studies the topic every day.

But we're still waiting for your brilliant paper that proves them wrong.

Sally V wrote:

I am pretty sure I am smarter than most climate scientists. They have a horrible track record.

And earlier you said it was all a big worldwide scientific conspiracy. We're waiting for your proof of that as well.

Citizen Runner wrote:...a hypothesis which at least has some clear physical basis and which is broadly corroborated by multiple lines of evidence.

Can you do me a favor and distill the multiple lines of evidence into a compelling case in layman's terms? I have read the IPPC scientific basis, but it's a hard read...

hmmmmmm? wrote:

Can you do me a favor and distill the multiple lines of evidence into a compelling case in layman's terms? I have read the IPPC scientific basis, but it's a hard read...

There is a brief at the link below which you may or may not find compelling. Note that they provide "basic", "intermediate", and "advanced" versions of the brief with links to the referenced literature to support each claim.

Citizen Runner wrote:There is a brief at the link below which you may or may not find compelling. Note that they provide "basic", "intermediate", and "advanced" versions of the brief with links to the referenced literature to support each claim.

http://www.skepticalscience.com/its-not-us-basic.htm

Thanks, I've had a look through the "advanced" tab. Unfortunately, a lot (most?) of the logic comes across to me as circular, being more of less of the form that "...our models assuming AGW predict this outcome, and we can't come up with natural forcing scenarios that produce the same outcome, ergo AGW is the only explanation..."

I'm left largely unconvinced...

hmmmmmm? wrote:

Thanks, I've had a look through the "advanced" tab. Unfortunately, a lot (most?) of the logic comes across to me as circular, being more of less of the form that "...our models assuming AGW predict this outcome, and we can't come up with natural forcing scenarios that produce the same outcome, ergo AGW is the only explanation..."

I'm left largely unconvinced...

I'm not surprised. Perspective on global warming correlates much better with world view than it does most anything else.

That said, we can go through the 10 points in the "basic" without relying on climate models at all.

1. We have a pretty good idea of the annual quantity of fossil fuels being burned and the atmospheric increase is about 50% of emissions with the rest absorbed by the oceans which reasonably makes the increase anthropogenic.

2. Atmospheric oxygen concentration is dropping proportional to the quantity of fossil fuels being consumed corroborating 1.

3. Changes in carbon isotope ratios in the atmosphere are consistent with 1.

4. Paleo records indicate that the increase is rapid by recent (geological time) standards and that the absolute levels of CO2 are currently considerably higher than they have likely been in at least 800,000 years.

Ergo, atmospheric CO2 level is higher than it's been in a very long time, it's growing rapidly, and it's us that's doing it.

5. Satellite observations indicate a reduction in outgoing radiated energy at frequencies expected to be attenuated by the spectral properties of CO2 and CH4 by direct observation over the satellite era.

6. Surface based observations indicate an increase in reflected radiation at those frequencies, so, by direct observation, essentially as first performed John Tyndall in the late 1850s, we know the greenhouse effect is increasing.

Ergo, spectral physics still applies by direct observations, no climate models required. The link doesn't go into it, but we also have satellite observations which indicate that there is more energy going into the earth system that are going out. We also have observations that indicate the average energy reaching the earth from the sun hasn't changed significantly over the satellite era, so warming over that era can probably not be attributed "natural variation" of the sun.

7. Nights are warming more than days. Intuitively this is what one would expect if the warming were due to "more insulation", i.e. the earth radiating less energy and the opposite would be expected if warming were due to more energy coming in during the daytime. Models of the process may be required to quantify the effect, but not to determine the sign.

8. Troposphere warming and stratosphere cooling. The intuitive physical explanation is based on the understanding that CO2 absorbs and immediately re-radiates energy in some random direction. At low altitudes (higher pressures) that energy is likely to be reabsorbed and re-radiated many times proportional to the density of CO2 molecules. At sufficiently high altitudes (low pressure) the energy is likely to be radiated into space, so an increase in CO2 concentration increases the stratosphere's ability to radiate thermal energy and it cools.

9. The troposphere upper boundary is largely due to it's ability to hold water vapor. As it warms the altitude at which it can do so would be expected to get higher.

10. The ionosphere cools and contracts for the same reason as the stratosphere discussed in 8.

Even if the sceptic assertion "we can't come up with natural forcing scenarios that produce the same outcome, ergo AGW is the only explanation..." were the case, which I don't think is accurate, it doesn't relieve one of proposing a better alternative. This is supposing that one's objective is converge on an accurate understanding of the science.

View on AGW correlates with world view?

I assume that is a snide crack if some sort. Care to elaborate and explain what part of my world view correlates with what I've said about climate change?

hmmmmmm? wrote:

Plus I can think of several cases where a stronger consensus was proven wrong... Y2K, WMD in Iraq, the sun revolving around the earth... Of course there are many, many other cases where the strong majority opinion was proven right, and that does factor into my thinkin

FWIW, the Y2K bug was quite real. I personally saw plenty of code that exhibited the problem. I worked for a major airline at the time and I can tell you that over half of our IT budget was spent on Y2K alone.

But we knew about it in plenty of time and we fixed it. Billions of dollars were spent on Y2K. Worldwide, we fixed most of the code. But there were still many documented cases of the bug that caused problems on 1/1/2000.

Thankfully, the disaster scenarios were averted because we didn't have to contend with idiots claiming that it was all a conspiracy.

However, if everyone took the attitude of the anti-AGW ostriches, we would have seen some really nasty problems.

Zombies everywhere wrote:

Yes, the overwhelming scientific consensus. Enlighten yourself before buying into anything wholesale..

http://www.plosone.org/article/info:doi/10.1371/journal.pone.0005738

Seriously? You think that because there are a few cases of scientific fraud in a wide range of fields that this disproves AGW? Maybe it disproves science altogether?

The amazing thing about AGW research is its dearth of documented fraud cases. If there is one thing that the anti-AGW crowd has done it is to make climate scientists even more careful. Not only are they scrutinized by their peers, they are also scrutinized by polluters who have a huge monetary interest in discrediting them.

So where is the fraud? Where is the evidence of conspiracy?

Thanks for this, maybe I should have started with the "basic" tab rather than the "advanced tab:

I will admit I have not read very much about these various indicators of the greenhouse effect, so I need to take the time to do some reading, absorb what I read, ruminate a bit and see whether the needle moves...

Meanwhile, a few comments from things I have read that have some bearing, in relation to your numbered points. However, please expand on your crack about my world view, I'd like to know what you think you can infer.

2. A correlation does not imply causation. Yesterday I was engaged on another discussion about wealth versus income ratios and I happened to compare them to the DJIA. I noticed that the DJIA since 1900 resembles the global temperature anomaly plot. You might be interested to know that the global temperature anomaly correlates better with the DJIA index than it does with atmospheric CO2 levels.

4. Paleo records simply cannot be compared directly with real data, on the one hand. And on the other hand it's not clear from the paleo records if temperature changes followed CO2 changes or vice versa. The inferred atmospheric CO2 levels obtained from ice cores have to be considered to represent average conditions over some long time period (centuries), and as such would need to be compared with measurements smoothed to represent century-scale averages, not decadal or annual values.

5. This is interesting and I must read more.

6. Ditto

I can't really comment on the other points. Anyway, you've given me some new (to me) information to chew on, so thanks for that. Now please elaborate about my world view...

Hmmm from the phone wrote:

View on AGW correlates with world view?

I assume that is a snide crack if some sort. Care to elaborate and explain what part of my world view correlates with what I've said about climate change?

Everyone filters data through the lens of their personal identity and pretty much everyone believes themselves to be to be a rational neutral observer. If everyone were in fact a rational neutral observer, one would expect consensus to increase proportional to one's knowledge of a topic. For a number of divisive issues, including global warming, the opposite is true, at least until one gets to the very highest levels of subject expertise.

This suggests, and my experience is, providing evidence one feels is significant to someone with a different perception isn't likely to dent their perception. Rather, it's likely to make them more defensive of their prior position.