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A troubling idea about climate change found new evidence in its favor

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Re: A troubling idea about climate change found new evidence in its favor

#101

Post by eric_h »

sathackr wrote: post #91
eric_h wrote: post #56

Earlier quoted context omitted.

Much as I like Randall Munroe and xkcd, I don't see any sources cited in that comic. I don't know that we know, precisely, how fucked we are yet, but I do think it's clear that humans are having an effect, and we know very convincing reasons for why we're having an effect, so we should work to reduce that effect regardless of whether we're fucked in 100 years if we continue this way, or if it will take 1000.

He cites his sources on the right near the top. > SHAKUN ET.AL. (2012), MARCOTT ET.AL.(2013), ANNAN AND HARGRAVES (2013), HADCRUT4, IPCC

I stand corrected. Thanks.

Re: A troubling idea about climate change found new evidence in its favor

#102

Post by thrw_skpt »

Cretin2 wrote: post #90
wtvanhest wrote: post #54

Earlier quoted context omitted.

There are major costs associated with cutting carbon emmissions before we have better technology. That is why people are questioning the 'science' of global warming. If we as a species are wrong about global warming in either direction, that is a big problem.

There are far greater costs to not cutting emissions now. 15-40% of CO2 remains in the atmosphere for upwards of 1000 years: https://www.skepticalscience.com/co2-residence-time.htm

Your link pretty much says "on average the CO2 stays in the atmosphere for 3-4 years, but if we change the definition, then it's up to 1000 years".

Re: A troubling idea about climate change found new evidence in its favor

#103

Post by Cretin2 »

thrw_skpt wrote: post #102
Cretin2 wrote: post #90

Earlier quoted context omitted.

There are far greater costs to not cutting emissions now. 15-40% of CO2 remains in the atmosphere for upwards of 1000 years: https://www.skepticalscience.com/co2-residence-time.htm

Your link pretty much says "on average the CO2 stays in the atmosphere for 3-4 years, but if we change the definition, then it's up to 1000 years".

No it does not. For a supposed MIT grad with a PhD I would expect excellent reading comprehension and the ability to understand scientific fields even when outside of your main one. Given your comments and misunderstandings here and elsewhere I am inclined to think you are not. Read the IPCC reports, if you don't have time, look at the summary for policy makers, particularly the physical science basis.

Do you understand the difference between average and 15-40%? How about the difference between average and median, non-normal distributions, etc.?

There's no changing of definitions from anyone except yourself in your misleading "quote".

Here's a more accessible article: http://www.nature.com/climate/2008/0812/full/climate.2008.12...

Re: A troubling idea about climate change found new evidence in its favor

#104

Post by pas »

wtvanhest wrote: post #45
woodandsteel wrote: post #41

I have a question for the anthropogenic climate change doubters and deniers out there. You say either that it is certain that human activity is not having a significant influence on the climate, or it is not certain whether or not it is. My question is, it there any sort of scientific evidence that might be discovered in the future that would lead you to change your mind, and if so what would it be? Or is you view si…

I am not a "denier", but I do struggle with the evidence I have read as most of it has too much subjectivity or is based on meta studies where all underlying papers are highly subjective. What is missing from the debate is 2-3 papers that are agreed on to be the clearest evidence that temperatures are changing due to human inputs. Calling people 'deniers' is an ad hominen attack that doesn't prove anything, and most…

The IPCC report is that, a series of papers that reviews everything and presents it in a technical but topical way.

See also: https://www.youtube.com/watch?v=RffPSrRpq_g

Re: A troubling idea about climate change found new evidence in its favor

#105

Post by Cretin2 »

thrw_skpt wrote: post #97
woodandsteel wrote: post #41

I have a question for the anthropogenic climate change doubters and deniers out there. You say either that it is certain that human activity is not having a significant influence on the climate, or it is not certain whether or not it is. My question is, it there any sort of scientific evidence that might be discovered in the future that would lead you to change your mind, and if so what would it be? Or is you view si…

I see several things about the climate science that can be substantially improved. * general discourse. Whenever someone raises some objection, the response is not a thoughtful argument, but many times a quick dismissal. you are certainly not one to do that, it is much appreciated * unfalsifiability. scientific theories should be falsifiable. anything else is religion or politics. For example, what happens if there i…

I think you need to understand magnitudes: "For example, what happens if there is a large volcano, or something like Saddam burning thousands of oil wells in Kuwait. I read somewhere that some climate models did check their predictions against the actual outcomes, and this is good. More evidence of this type would be great."

These are trivial in the global context.

Here's a good resource on the global carbon cycle: https://www.ipcc.ch/pdf/assessment-report/ar5/wg1/WG1AR5_Cha...

and to my point from your other comment, this is from the link above: . Within a thousand years, the remaining atmospheric fraction of the CO2 emissions (see Section 6.3.2.4) is between 15 and 40%, depending on the amount of carbon released (Archer et al., 2009b).

The models are performing very well:

https://www.theguardian.com/environment/climate-consensus-97...

Looking to Freeman Dyson as a climate expert is bordering on wilful ignorance: https://www.inverse.com/article/7154-admitted-climate-change...

You really need to get your feet wet in this and read the actual research rather than look at people on the periphery that satisfy your biases.

Re: A troubling idea about climate change found new evidence in its favor

#106

Post by Tycho »

Oletros wrote: post #100
Tycho wrote: post #93

Earlier quoted context omitted.

If there is not a good answer to that question, then I would reject the hypothesis outright. If there is a good answer, then I would accept it as a working hypothesis, unless any other screaming contradictions come up. I would also find it persuasive to see people with skin-in-the-game make informed decisions. For instance, selling off desirable waterfront properties because they believe rising sea levels will make t…

> If there is not a good answer to that question, then I would reject the hypothesis outright. If there is a good answer, then I would accept it as a working hypothesis, unless any other screaming contradictions come up. So, you won't accept it in any case

Why should I accept any hypothesis that hasn't be proven either by controlled experiment or logical/mathematical deduction? The only appropriate stance in such situations is "I currently think this hypothesis is likely/unlikely to be true" and act accordingly (in a risk-adjusted way) but keep an open mind.

I think it would be interesting to turn the question back on you: what evidence, if any, would convince you that the broad scientific community has been seriously wrong about AGW and that we are not facing any real crisis?

Re: A troubling idea about climate change found new evidence in its favor

#107

Post by wtvanhest »

Oletros wrote: post #99
wtvanhest wrote: post #86

Earlier quoted context omitted.

You are misunderstanding. Basically, you are commenting in circles. I am looking for, no, pleading with you to present... is a clear and compelling case that global warming is at least partially caused by humans. When you or anyone else presents that evidence, I and others will apply various techniques to determine how credible that evidence is. One of those techniques I will apply is to examine subjectivity vs objec…

> I am looking for, no, pleading with you to present... is a clear and compelling case that global warming is at least partially caused by humans If you think that in 2017 there is no clear and compelling case that global warming is at least partially caused by humans I think you won't accept any fact about it

That is what everyone says, but no one actually presents the paper or research that convinced them. I would think that if I held a deep conviction about something I would know why I held that belief. Unless I just decided that all my friends and TV people said something is true so it must be. That would be very alarming though...

Re: A troubling idea about climate change found new evidence in its favor

#108

Post by thrw_skpt »

Cretin2 wrote: post #105
thrw_skpt wrote: post #97

Earlier quoted context omitted.

I see several things about the climate science that can be substantially improved. * general discourse. Whenever someone raises some objection, the response is not a thoughtful argument, but many times a quick dismissal. you are certainly not one to do that, it is much appreciated * unfalsifiability. scientific theories should be falsifiable. anything else is religion or politics. For example, what happens if there i…

I think you need to understand magnitudes: "For example, what happens if there is a large volcano, or something like Saddam burning thousands of oil wells in Kuwait. I read somewhere that some climate models did check their predictions against the actual outcomes, and this is good. More evidence of this type would be great." These are trivial in the global context. Here's a good resource on the global carbon cycle: h…

I'm not sure why you rush to dimiss me like that. The question was "what would make you believe that AGW is real", and I mentioned that the climate models should be falsifiable. We know climate models cannot predict the weather beyond 2 weeks or so, but climate scientists claim that this is not their point. Fine, it's not their point. Then how do I know that this black box is correct, besides peer review? A model should state: X should happen (where X was not used in the calibration). Until yesterday I knew of only 2 such predictions: a periodic climatic phenomena similar to El Nino [1] (where the result is mixed) and the global temperature changes following the Pinatubo eruption [2] (where the result looks promising).

I didn't read your link where you say the models are performing very well, but I'll do it. Thanks.

Elsewhere in this thread, you resort to a bit of lower argumentation tactics ("supposed MIT PhD"). May I suggest you read Paul Graham's essey on desagreements [3] ? In return, here's a bit of mea culpa for my facile attack that the quoted very long life of the CO2 is only the result of a change of definition: while technically I was right, the definition change is one in good faith, and my critique was not.

[1] https://www.ipcc.ch/publications_and_data/ar4/wg1/en/ch8s8-4... [2] https://www.giss.nasa.gov/research/briefs/hansen_02/ [3] http://www.paulgraham.com/disagree.html

Re: A troubling idea about climate change found new evidence in its favor

#109

Post by Cretin2 »

thrw_skpt wrote: post #108
Cretin2 wrote: post #105

Earlier quoted context omitted.

I think you need to understand magnitudes: "For example, what happens if there is a large volcano, or something like Saddam burning thousands of oil wells in Kuwait. I read somewhere that some climate models did check their predictions against the actual outcomes, and this is good. More evidence of this type would be great." These are trivial in the global context. Here's a good resource on the global carbon cycle: h…

I'm not sure why you rush to dimiss me like that. The question was "what would make you believe that AGW is real", and I mentioned that the climate models should be falsifiable. We know climate models cannot predict the weather beyond 2 weeks or so, but climate scientists claim that this is not their point. Fine, it's not their point. Then how do I know that this black box is correct, besides peer review? A model sho…

"I'm not sure why you rush to dimiss me like that." Perhaps you should re-read how you dismissed what I put forward and you will understand the favor I returned with supporting evidence and perhaps too much snark.

This comment touches on the ENSO topic you are referencing to and discusses falsifiability: https://www.skepticalscience.com/argument.php?a=308#101174

I'd be interested to know what you're reading that brought you these arguments as they seem to be targeting them. So it is evident that they are being passed around circles of skeptics (not saying deniers).

There's a big difference between a climate model and a weather model and I believe you're familiar with the differences between long term changes (climate) and short term ones (weather). Just like we can't predict the interaction of every atom in a balloon yet we can predict how they will act as a whole when inflating one.

"In return, here's a bit of mea culpa for my facile attack that the quoted very long life of the CO2 is only the result of a change of definition: while technically I was right, the definition change is one in good faith, and my critique was not."

Thanks, I guess....but you are not technically right. You completely altered the state of my argument. I wasn't talking about the average. 15-40% (depending on the IPCC emissions projection) of CO2 remains in the atmosphere for upwards of 1,000 years. If our projections of climate change are correct we're in very big trouble as we've already locked in a significant amount of warming.

Additionally, you should be looking at AR5's physical science basis files, not AR4's if you want to be following the state of the science 4+ years ago instead of 10+.

Re: A troubling idea about climate change found new evidence in its favor

#110

Post by thrw_skpt »

Cretin2 wrote: post #109
thrw_skpt wrote: post #108

Earlier quoted context omitted.

I'm not sure why you rush to dimiss me like that. The question was "what would make you believe that AGW is real", and I mentioned that the climate models should be falsifiable. We know climate models cannot predict the weather beyond 2 weeks or so, but climate scientists claim that this is not their point. Fine, it's not their point. Then how do I know that this black box is correct, besides peer review? A model sho…

"I'm not sure why you rush to dimiss me like that." Perhaps you should re-read how you dismissed what I put forward and you will understand the favor I returned with supporting evidence and perhaps too much snark. This comment touches on the ENSO topic you are referencing to and discusses falsifiability: https://www.skepticalscience.com/argument.php?a=308#101174 I'd be interested to know what you're reading that brou…

I guess I skipped one or two steps in my mea culpa, so I'll cover them here.

You posted this link https://www.skepticalscience.com/co2-residence-time.htm

In this link, after a short introduction, we learn that there are about 750 GT of CO2 in the atmosphere, and about 200GT enter and leave the atmosphere each year, which is about 27%. CO2 molecules are indistinguishable from one another (leaving aside the trace amounts of molecules that contains isotopes different from C12 and O16). A molecule produced by human emissions does not look in any way different from another CO2 molecule. Moreover, in no time all the anthropogenic CO2 is equally mixed in the rest of the CO2 (by diffusion). Because of that the proportion of CO2 that stays in the atmosphere for a given time follows an exponential law with a decay coefficient of -log(1-0.27)=0.19 (see note). So out of all the CO2 in the atmosphere at a given time, only 83% stays there for 1 year, only 15% for 10 (uninterrupted) years, and only 5.6*10^(-9) after 100 years. And this is true both for all the original CO2 as for the anthropogenic CO2.

Now, if you change the definition of what it means for CO2 to remain in the atmosphere, then you get the long life you mentioned, but you do need to change that definition.

And this has nothing to do with averages vs medians or percentiles or other statistical concepts (which by the way, I am very familiar with).

(note) I'm skipping another step there, how to go from indistinguishability of CO2 to the exponential law, but if you want me, I can fill that in too.

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