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What's Really Warming the World?

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Re: What's Really Warming the World?

#501

Post by deciplex »

sgt101 wrote: post #351
wnewman wrote: post #60

Earlier quoted context omitted.

"The real trick is to see how well your model extrapolates from the data you have out into the future." That is the most common way to show the modeller is not shamelessly overfitting.:-| Another way, though, is less common but not vanishingly uncommon: the model may be so much simpler than the data it fits that overfitting is not a plausible explanation. (Roughly there are too many bits of entropy in the match to th…

Well - that's true apart from co-incidence. You can have a very simple theory which says "x is directly caused by y" and there is a lot of good data, and a great fit. But it's kist a co-incidence and breaks down immediately. Occam's razor is a rule of thumb and an aesthetic boon, but nothing more. The real test is that you have a theory that is meaningful and has explanatory power. If it grants insight on the mechani…

> Occam's razor is a rule of thumb and an aesthetic boon, but nothing more.

Occam's razor is a bit more than that. It isn't just that given a theory X and a theory Y = X + ε, both of which fit the facts, you should prefer X because it's "cleaner" or more aesthetically pleasing or whatever. You should prefer X because you can prove it is more likely to be true.

https://en.wikipedia.org/wiki/Solomonoff%27s_theory_of_induc...

Re: What's Really Warming the World?

#502

Post by MaysonL »

jasonkester wrote: post #3

Cool visualization. It's worth keeping in mind that the modeled data lines up with reality because it's supposed to. That's how you calibrate your model, by making sure it fits reality. The real trick is to see how well your model extrapolates from the data you have out into the future. As in, if you feed it data up to, say, 1990, will it correctly spit out 2015 temperatures that fit the reality of 2015, or will it s…

The thing is, it's not just the temperature measurements fitting the greenhouse gases. It's also all the biological and physical evidence. Bird migrations, plant species ranges, glacier and ice cap shrinkage and growth, permafrost melting, polar vortices occurring, etc.,etc.,etc. Screw the models: look at the reality.

Re: What's Really Warming the World?

#503

Post by imh »

kevindication wrote: post #10
elorant wrote: post #5

Earlier quoted context omitted.

Same here. I can't seem to get it to scroll and show headers at the same time. I tried scrolling really slowly and it still stops showing headers after third graph. For a venue as big as Bloomberg you'd expect them to test it thoroughly before publishing.

Does it work better if you click the black arrow at the bottom of each slide?

not for me

Re: What's Really Warming the World?

#504

Post by seandhi »

spdustin wrote: post #347
nsxwolf wrote: post #162

Earlier quoted context omitted.

Deniers get mocked for bringing up cold winters ("weather is not climate, you MORON!"), but warmists have no problem blaming every hurricane and tornado on global warming.

"Warm" = "more energetic", in every sense of the word. In my own mind, I think of global climate change in a more simplistic way: global energy change. We humans are releasing, in short order, energies that took natural processes millions of years to convert to the form that we're liberating. I can't think of any other philosophy or activity done by humankind that wantonly, aggressively and cavalierly "blows the wad"…

Except that the data doesn't support what you're saying... There's no uptrend in tornados, in accumulated cyclonic energy, or in drought.

I say this as someone who doesn't really consider himself a "skeptic". The scientists who are working in the field know more than I ever will, but I do try to separate the media hype from the legitimate science that is taking place. When people say that X event was caused by climate change, I can't help but think of this data, which doesn't support those assertions.

https://www.evernote.com/l/AUF3iT4Tq_BBW5EaQTI_QBwBfGNKOu_3N...

Re: What's Really Warming the World?

#505

Post by marcus_holmes »

cholantesh wrote: post #353
marcus_holmes wrote: post #246

Earlier quoted context omitted.

ad-hominem. Who cares who wrote it, what does it say?

Really? You think it doesn't matter that the primary author on a paper about climate science doesn't even have an undergraduate-level education in the subject? That the second one credited has a history of accepting large sums of money to write papers endorsing spurious claims DIRECTLY RELATING to climate change?

A lot of the IPCC lead authors are paid by NGO's (like Greenpeace) with a vested interest in climate alarmism. Do we discount their work too?

Climate science covers a lot of different areas, everything from economics, through hard chemistry and fluid dynamics, to pure statistics. No one person can be an expert on all of this, and no one qualification will make anyone competent in all of them. Experts from related disciplines are perfectly qualified to speak on "their" areas of climate science.

Re: What's Really Warming the World?

#506

Post by ridgeguy »

300bps wrote: post #147
jasonkester wrote: post #3

Cool visualization. It's worth keeping in mind that the modeled data lines up with reality because it's supposed to. That's how you calibrate your model, by making sure it fits reality. The real trick is to see how well your model extrapolates from the data you have out into the future. As in, if you feed it data up to, say, 1990, will it correctly spit out 2015 temperatures that fit the reality of 2015, or will it s…

Cool visualization. I agree, but I have to say their imagination on what other things might be causing warming is not very robust. For just one example, there are at least two major effects of burning: 1. Release of chemicals into the atmosphere (ex: carbon dioxide) 2. Directly heating the atmosphere There are literally billions of air conditioners, heaters, cars, factories, etc that all generate heat. The effect of…

This doesn't add much to what earlier respondents have said, but it was five minutes of fun to do.

The mass of Earth's atmosphere is about 5e18kg. Specific heat of dry air is about 1kJ/kg-°K. Total human energy consumption in 1990 (just to pick a year) was about 102,000 TWhr (3.6e20 J/TWhr. Wikipedia for most of the numbers.

Assuming all the energy consumed resolved into heat and only heated the atmosphere, then I get the one-year temperature increase due to human energy use during 1990 as about 0.073°K.

Less than I would have guessed, and probably wrong by at least a couple orders of magnitude due to simplifying away 99% of what's really happening.

Re: What's Really Warming the World?

#507

Post by Tycho »

DanBC wrote: post #427
JoeAltmaier wrote: post #335

Earlier quoted context omitted.

Confused: this is the hottest year on record worldwide. In what way is this 'taking a break'?

And the ten hottest years have been since 1997?

This makes me think of when financial journalists/broadcasters constantly report that the SPX or the DJIA or the FTSE or whatever are hitting 'all time highs' and it's a really useless piece of information. Investors want to know how much it went up by on the day (and what he trend of the last few days/months has been), the fact that it poked through to a new high level is not important.

Re: What's Really Warming the World?

#508

Post by visarga »

jasonkester wrote: post #3

Cool visualization. It's worth keeping in mind that the modeled data lines up with reality because it's supposed to. That's how you calibrate your model, by making sure it fits reality. The real trick is to see how well your model extrapolates from the data you have out into the future. As in, if you feed it data up to, say, 1990, will it correctly spit out 2015 temperatures that fit the reality of 2015, or will it s…

> if you feed it data up to, say, 1990, will it correctly spit out 2015 temperatures that fit the reality of 2015, or will it spit out crazy 2015 predictions like the models that were built in 1990 did

Yeah, so they pick models until they find one that fits both 1990 and 2015? That would be using the test data to train the model - like the Baidu approach.

Re: What's Really Warming the World?

#509

Post by dbdr »

tosseraccount wrote: post #255
dnautics wrote: post #117

Earlier quoted context omitted.

He does also maintain one of the satellite records, which does show global warming over the period 1960-2000 (not so much the last 10 years because of the global warming hiatus).

Did any models predict the "global warming hiatus" ?

Apparently, the past models did not, because they did not model the long term interaction of the oceans with the atmosphere, and the current "hiatus" is mostly about the atmosphere temperatures, while most of the warming is currently happening in the oceans.

The more sophisticated current models do match the recent observations if you feed them the past data:

http://www.theguardian.com/environment/2014/sep/09/research-...

Re: What's Really Warming the World?

#510

Post by EdiX »

cactusface wrote: post #455
EdiX wrote: post #450

Earlier quoted context omitted.

It boggles my mind that people use the term sealioning unironically. How can it possibly be that a sensible person thinks it's ok to make a hateful statement in a public place and when someone asks clarification about it they are the harassers?! You are not a priest preaching to the ignorant congregation, if you don't want to deal with the bullshit get off the fucking podium.

Here's my sealion of a question. What parts of climate change research are actually backed up by the scientific method (experiments with falsifiable hypotheses and all that) and what parts are more akin to natural history or something else? To clarify, I believe humans caused the problem (it appears that stating this makes people like you more, which is weird, but ok) but I cringe every time I hear the word science a…

>What parts of climate change research are actually backed up by the scientific method (experiments with falsifiable hypotheses and all that) and what parts are more akin to natural history or something else?

I do not generally get involved in the climate change debate because it has multiple problems: it happens on scales (both time and space) that humans have difficulty observing, it is about a system with lots of feedback that could very well behave chaotically, direct observations of the phenomenon are limited compared to its timescale, experts of the subject are operating under perverse incentives, it is highly politicized and almost everything that's easy to read about the subject is blatant propaganda (see all the climate change denialist posted in this thread as well as the OP).

Your question is hard to answer because it assumes there is a shared and agreed upon definition of the word "science" that can be used to determine with certainty wethere something is science or not.

> Is it like a social science? I think someone told me that we know for sure that greenhouse gas emissions cause ozone depletion but I can't remember anymore. What is the actual hard science here?

I think it is in better shape than the average social science, the greenhouse effect and the ozone depletion are two separate phenomena, this [1] is the experiment that explains how the greenhouse effect works, the wikipedia page about ozone depletion explains the chemical reactions that lead to that.

[1] https://en.wikipedia.org/wiki/Svante_Arrhenius#Greenhouse_ef...

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