The Definitive Global Climate Change (aka Global Warming) Thread -- General Discussion and Questions

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TedBundo's picture
TedBundo
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Thanks for that link the

Thanks for that link the articles really made me think a lot and I liked the interactive map. I'd say that climate change is evident where I'm from.... the landscape clearly shows it and our football field at the local high school is dying because of the lack of rain and higher than normal temperatures.

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Mark Cochrane
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Perspective on Arctic Sea Ice

Another year of low ice cover in the Arctic. So what's new? Few know about this and fewer care. The decline has been going on so long that we fail to be shocked anymore. In the graph below the gray area is where 95% of years should fall. We are well below that area, yet again, about where we were last year. The dashed line is 2012 when we experienced the lowest sea ice cover (in September). Depending on the vagaries of the weather, this year may or may not be the lowest on record but just looking at the area of cover is misleading, since it tells you nothing about the thickness of the ice.

As the ice cover expands in the cold Arctic winter it covers the ocean and traps the heat it contains. This allows the air temperatures to drop very low above the ice. Think of the ice as the covers on your bed. If your covers are thick your body heat stays contained even on a cold night. If you have just a thin sheet you don't stay quite so comfortable.

In the Arctic, sea ice gets thicker the older it gets as it goes through successive winters. As recently as the 80s, 30% or more of the ice cover was 5+ years old and first year ice was not much different at about 35% of the area. Now, older ice area has been reduced to <5% while first year ice makes up nearly 70% of the area.

Thin ice breaks easier during Arctic storms and, much like crushed ice in your drinks, melts faster. Open water in the Arctic summer enjoys 24 hours a day of sunlight. Ice reflects most of the heat, but open water absorbs almost all of it. This makes the Arctic ocean warm more and more year after year, which in turn makes the formation of new ice in teh winter harder and harder until later in the year, after enough heat escapes the surface waters. That heat plays havoc with the regional weather in the Arctic. The Polar Vortex is weaker and slower to form making it more likely that cold Arctic air will spill out in bursts across North America and Europe.

The 'death spiral' map shows how sea ice volume is circling the drain that will one day, in the not too distant future, end with an ice-free Arctic summer. How much ice have we lost in the last 4 decades? Comparing April 2017 to April 1979, the reduced volume of Arctic sea ice would be nearly enough to cover the entire combined land area of both Canada and the United States with 1 meter of solid ice.

Alas, the only thing poorer than the human race's ability to understand the exponential function and large numbers is its grasp of geography...

Mark

 

 

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PaulJam
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Football score analogy

Thanks for you post, Mark - I have a semi-cynical suggestion on how to communicate ice loss:  compare it to average pro football scores:

Take the average minimum extent from the earliest period that we have data for, then calculate how far out on a normal distribution the 2017 ice coverage minimum is in comparison.  If it is +2 SD, then take the average pro-football winning football score, and figure out what the +2 SD equivalent is.  

I'm too time pressed to dig for the football stats right now, but the average winning score is 29 points.  I'd bet that the minimum ice coverage loss equivalent for a winning football score is around 70 or 80 points.

Then if this message is emphasized by the mainstream media (eye-roll), then just maybe people can understand the extremity of the changes that are now afoot.  If indeed we are entering a process of abrupt non-linear climate change (as I suspect/fear), then Guy McPherson is thoroughly vindicated, and we are left with having to be personally satisfied with merely doing the right thing, rather than thinking that there will be any real beneficial outcomes to our actions.  

Looking at this data and thinking about positive feedback loops that are now engaging, it is very possible that we are right now beyond the reach of even a Marshall-plan like response.

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sofistek
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No vindication

Paul

If indeed we are entering a process of abrupt non-linear climate change (as I suspect/fear), then Guy McPherson is thoroughly vindicated ...

Even this would not "thoroughly" vindicate GM. GM's hypotheses are based, in large part, on flawed interpretations of the science and an over-reliance on some anonymous poster (or set of posters) named Sam Carana, who is not averse to, effectively, making stuff up. The notion of non-linear changes have been posited by the IPCC for a long time. We might well be entering such a phase (I don't know) but that does not translate into McPherson's opinion of total extinction by mid-century (or earlier). So, no, it would not vindicate GM.

Tony

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Sam Carana

Tony - I never know what to think about the Arctic News website myself, so am interested in all opinions/thoughts.  I read it often (among other AGW sites) but am left with an agreement with myself to both not fully believe it and yet not dismiss outright.

There are dual tendencies at work when trying to make heads or tails of this stuff - on one hand, the tendency for hyperbole just to make waves and get peoples attention, or simply to indulge an individual's emotional blind spot of self-righteous misanthropy; and on the other hand the tendency to dismiss predictions of the most adverse of outcomes on the basis of the disagreeableness of where the data is pointing.  I don't have the time to dive deeply into the scientific sausage making behind sites like Arctic News, so am left with opinions of others and my own pondering.

 

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sofistek
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Carana

Paul,

One only has to look at the frequency of Carana's taking a short period of data points and extrapolating, only for the projections to be falsified by the next period of data. Carana leaps on such periods only to pander to the doomers. He or she is also not averse to mixing datasets in one graph or to graph out data points that aren't actually data points. Of course, there will always be the odd bit of interesting opinion amongst all of that but you will rarely, if ever, see critical comments in the comments section, because they don't get published (I've tried many times).

No, if you want reasonably accurate news about the Arctic, try Neven's blog. He's not as prolific as Carana, but there are also some interesting discussions in the comments sections of posts, and in the related forum.

Tony

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sofistek
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One to go

Deniers and contrarians have been relying on data series that don't measure surface warming, which, for the lower troposphere, have shown a smaller warming trend than surface measurements. The RSS TMT data set was corrected a couple of years ago and now it's the RSS TLT data set. Well, once biases have been removed, TLT shows an even stronger warming than surface records, though still not as strong as some models suggest.

I'm now waiting for the usual suspects to tell us why this is a conspiracy or why their last remaining hope, the UAH TLT data set (currently still in a beta version), is a far better measure.

I'm not sure what data set Mark and Stan agreed on for their bet but it's sure starting to look like a lost cause for Stan.

Tony

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Data Point

Here's a new data point. Record dry spell out here in on the West Coast. Now it's burning.

http://cliffmass.blogspot.com/2017/09/smoke-front-hits-western-washingto...


 

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sofistek
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Contrarian Arguments Examined

This recent paper by Benestad, et al, examines many contrarian papers (the ones outside the 97% concensus) and explains the errors in them. Perhaps the contrarians ought to now examine this paper to see if there are errors in the analysis?

Good luck.

Tony

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Cyclical?

I remember my professor made a similar argument 12 years ago or so in University...
What do we think? apologies if this has already been discussed or shown, big thread to get through!


 

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Cyclical?

...I see cycles have been brought up, starting from the first page :)

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Mark Cochrane
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Mount Agung

All,

Not dead yet... Actually I have been in the midst of an extended relocation, hence my disappearance from this thread.

In any case, for those interested, the apparently imminent eruption of Mt. Agung on the island of Bali in Indonesia is potentially going to be globally important for climate in the next few years.

The last time Agung erupted was in 1963 and it resulted in a 0.1 to 0.4 C reduction in global temperatures over the next two years. In comparison, Mt. Pinatubo in the Philippines cooled things by 0.5C for 2 years after the 1991 eruption. It is uncertain how big this upcoming eruption will be as of yet.

In order for an eruption to become climatically significant it needs to inject materials (especially sulfur dioxide) into the stratosphere. In the tropics that means the eruption needs to push materials higher than 16 km. If the eruption height is in the 20-25km range then we will likely have globally significant effects on climate.

For a volcanic eruption to have global impacts it has to be in the tropics since equatorial eruptions can spread aerosols into both hemispheres. Unless we get a massive eruption (think Tambora in 1815 = Year without a summer) then the regional climate impacts will probably be relatively mild, though potentially nontrivial. Primarily over continental regions of the northern hemisphere, summers will be cooler (max effect at around 40 degrees latitude) while a stronger Polar Vortex will yield warmer winters for a couple years. If things mimic the Pinatubo eruption then most of North America, Europe and Siberia will be much warmer in the winter while Alaska, Greenland, the Middle East and China will be cold. The southern hemisphere sees less magnitude of impacts because of the relatively greater amount of ocean (releases heat), but the impacts last longer.

Within two years the eruption climate effects will appear to be over but there will be a sort of echo in the climate system that can last for decades caused by the cooling of ocean waters during the period when volcanic aerosols block some of the sunlight. This could help reduce the absolute rate of warming for a while but not enough to dramatically change our future climate projections from greenhouse gas warming.

By way of coincidence, I am supposed to be heading for Indonesia on unrelated matters next week....

Mark

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sofistek
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Game Over?

Good to see you back, Mark, and good luck in Indonesia.

Maybe a few big volcanic eruptions close together will give us some respite. With news of recent research showing tropical forests are now a net source of emissions and that methane emissions from livestock are 11% higher than estimated, it seems like it's game over for humans versus nature. Nature will win, of course, but humans will have left their mark on it, perhaps for ever, if any nature survives. It's rather ironic that this research comes around the time that the latest estimates of emissions from energy show a continued stalling or slowing. We just can't stop ourselves from ensuring that atmospheric carbon continues to accelerate. This is because the environment always comes second to the economy for most people.

Oh well, it's oddly enthralling how we can't seem to help ourselves and even still have those who feel they need to pretend that there's nothing wrong or that what is wrong is easily manageable. I heard a fact twice recently, that I hadn't heard before: humans and their animals (for pets or food or other pleasure) now constitute 98% of the animal biomass on this planet, pretty much the reverse of how it used to be. Perhaps that illustrates just how f*d up we are.

Tony

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Weogo
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Drawdown

Hi Mark and All, 

Are you familiar with this book? :

 http://www.drawdown.org/

I heard one of the lead authors speak this evening.
 
I would not have guessed the top solution to climate change:
 
 http://www.drawdown.org/solutions-summary-by-rank
 
Thanks and good health,  Weogo
 
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“Predicting the climate is vastly simpler”

Five years ago Mark made the claim “ “Predicting the climate is vastly simpler. “ (in comparison to predicting the weather)

 

I challenged him to live up to the standard he set for others regarding claims.


Me wrote:

To quote you...... "Stan, if you have any credible source(s) for this statement please provide it/them. Otherwise retract your assertion or qualify it as solely an unsupported opinion that you seem to hold regardless of scientific observations to the contrary."

Strike out Stan and insert your name....

His response was this

 


Mark Cochrane wrote:

For global climate models however the analogy is the need to get the temperature right but you get to take the average of estimates for 30 years of 365 days each (give or take a few leap year days) at 5,000,000 locations. That is, you have about 55 billion attempts then you average them. The Law of Large Numbers (LLN) says that your difference from the mean temperature of the planet should be extremely small.

His argument is equivalent to saying 'Predicting the climate is easier than predicting the weather because I saw a dog run over on the motorway this morning'

In one of my attempts to get him to see the illogic of his claim, I said


Me wrote:

The law of very large numbers, as I read in an explanation, applies to non dependent random events where all the possible outcomes of each occurrence of the event are known.

(emphasis added here)

 

Marks responded with


Mark Cochrane wrote:

“”With regard to your questions on the law of large numbers (there are several, the weak, strong etc), we'd need a bonafide mathematician to parse the exact definition but I do not believe they only apply to discrete numbers or that all possible values must be predetermined. “”

 

In his original claim he provided a link to a wiki page on LLN, ( you should be able to click on the link in his claim quoted above) and in it states what LLN applies to.

How he got from Wiki's definition to “ they only apply to discrete numbers or that all possible values must be predetermined.” I don't understand, and he provided no source backing such a definition.

and the first words in the wiki page are ""In probability theory, the law of large numbers (LLN)......." and probability theory deal with RANDOM numbers. ( So in a way he is claiming the output of the climate models is random!!!!cheeky)

Despite my attempts, Mark has so far been unable to see how logically flawed his claim is.

To date the 'score' for being able to see the illogic of his argument is roughly, believers 0% skeptics 100%
 


Mark Cochrane wrote:

Who am I and why should anyone believe what I have to say on this subject? Well, I post under my real name so any search engine will pull me up on top. I am a research scientist and professor with an environmental engineering degree from MIT and a doctorate in ecology from Penn State. I am what is termed an 'interdisciplinary' scientist which means someone who works across many scientific fields. This gives me a broader view than many of my colleagues on issues such as climate change. I teach graduate classes on the subject but also have taught it to middle schoolers, at open venues, a local church, and through newspaper editorials.

 

I am gobsmacked that a person that said that of himself could come up with and defend such an illogical argument to back his claim.

 

It is not the only logically flawed argument he has presented in this thread, but it is certainly one of the most glaringly obvious.

How can he and his believers fail to see the illogic in his statements?

Who can see the illogic of his argument?

Without logic, you only have pseudo science........

 

Regards Hamish

 

 

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sofistek
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Meanwhile

I missed this paper, last year, by Rockström et al, which outlines the challenge presented by the Paris Agreement goals. With no meaningful action to mitigate yet visible, it seems highly unlikely that we'll manage to meet even the weakest of those Paris goals.

Abstract

The scale of the decarbonisation challenge to meet the Paris Agreement is underplayed in the public arena. It will require precipitous emissions reductions within 40 years and a new carbon sink on the scale of the ocean sink. Even then, the world is extremely likely to overshoot. A catastrophic failure of policy, for example, waiting another decade for transformative policy and full commitments to fossil-free economies, will have irreversible and deleterious repercussions for humanity's remaining time on Earth. Only a global zero carbon roadmap will put the world on a course to phase-out greenhouse gas emissions and create the essential carbon sinks for Earth-system stability, without which, world prosperity is not possible.

Tony

 

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Resource Efficiency Dropping and Other Problems

This discussion is quite good in terms of climate change overall, but the best part is actually an audience question at the very end where a researcher states that resource use efficiency is dropping at an annual rate of 0.8% and less than 0.1% of all material is recycled. When you top all of that off with moving away from fossil fuels to far less efficient alternative energy then you're really screwed:

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Stabu
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Resource Efficiency Dropping and Other Problems

This discussion is quite good in terms of climate change overall, but the best part is actually an audience question at the very end where a researcher states that resource use efficiency is dropping at an annual rate of 0.8% and less than 0.1% of all material is recycled. When you top all of that off with moving away from fossil fuels to far less efficient alternative energy then you're really screwed:

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Matt Holbert
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As someone who lives at a 10% avg. US footprint...

Stabu- Thanks for sharing the video. I have read several articles by Kevin Anderson but have never seen him speak. I plan to digest the contents of this video and respond in the next couple of days. Sort of the Trump method: Big announcement forthcoming. : )

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