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What's Really Warming the World?

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Re: What's Really Warming the World?

#331

Post by prawn »

paulhauggis wrote: post #226
paulhauggis wrote: post #113

Earlier quoted context omitted.

I also question how we know the difference between nature/cycles and man-made pollution. Here is a good example: https://en.wikipedia.org/wiki/Little_Ice_Age "Several causes have been proposed: cyclical lows in solar radiation, heightened volcanic activity, changes in the ocean circulation, an inherent variability in global climate, or decreases in the human population." It seems we don't even know how the little ice…

I bring up some simple questions and I am immediately silenced. I guess I didn't realize HN was anti-science and anti-intellectual.

Going a bit grey isn't being "immediately silenced". People can still read your comment.

I think you're reading too much into the "the science is settled" comment. It's a field where powerful interests work aggressively to discredit a majority view of scientists, and it's likely that some (magnified by the media) may use a term like that out of frustration to imply consensus and a wish to have policy makers progress on action.

I know it's easy to find an aberration on Wikipedia, but the pros know all that stuff, they live it every minute of the day.

Re: What's Really Warming the World?

#332

Post by phkahler »

asgard1024 wrote: post #238
phkahler wrote: post #163

Deforestation? They reject this because we replace forest with light reflecting materials which they claim causes slight cooling. Last time I checked, it's way cooler in a forest than standing in a parking lot. Nature uses the energy from sunlight to create biomass. Anything else either reflects it or turns it to heat.

> Last time I checked, it's way cooler in a forest than standing in a parking lot. Perhaps you forgot to account for the shade and humidity? (As an aside, I believe forests generate heat, just like any biological system. The best it can be seen during spring, the snow patches around plants will melt sooner.)

Nope. From a thermodynamic analysis, the energy is either reflected, turned into heat, or used to do work. Forests use more for work than any static object. The only open question in my mind is how much so. You do raise the point of emitting water vapor which adds a lot to the complexity. Also the rotting biomass will produce a lot of heat. But the production of dirt is probably still a net use of the energy. Remember, coal is old biomass and contains a lot of energy that came from the sun.

>> As an aside, I believe forests generate heat, just like any biological system.

You would be wrong in that. All chemical processes in the forest are ultimately powered by sunlight. Your body produces heat, but that's due to chemical reactions that primarily amount to burning fuel (fats are essentially hydrocarbons and the primary products of their "burning" is CO2 and H20 which exit through the lungs). Animals turn chemical energy into heat, but plants turn energy from light into chemical energy.

Re: What's Really Warming the World?

#333

Post by bildung »

tosseraccount wrote: post #317
bildung wrote: post #304

Earlier quoted context omitted.

> I want solid proof ... or , uh "almost proof". Proofs don't exist in sciences concerned with the physical world. For proofs to work in the real world, you'd need certainty that you have recognised and correctly measured every variable that could affect the outcome of an observation/experiment. The last philosophy of science that allowed proofs was positivism. For the natural sciences, it has been replaced by critic…

I'm curious. Gravity has not been proven to attract two masses, for instance?

> I'm curious. Gravity has not been proven to attract two masses, for instance?

Correct. That's why it's called the theory of gravity :) You would need Laplace's demon (https://en.wikipedia.org/wiki/Laplace's_demon) for a proof. "Proof" means absolute certainty. You only find that in math, not in the physical world.

Re: What's Really Warming the World?

#334

Post by scarmig »

drjesusphd wrote: post #295

Since I seem to be repeating myself all over this thread: It is basic physics (the optics of IR and visible light and thermodynamics) that trace amounts of CO2 and methane can significantly warm the atmosphere. We know physics pretty damn well, and if you do not accept this, there is no conversation. Sure, one should look at the data to see to what extent this is happening and there are all kinds of questions one can…

The science around climate change is well established--it's happening, it's man-made, and it will continue--but it's a bit more complicated than that. The physics suggests a relatively small increase in temperature (<1C); it's the positive feedbacks, particularly water vapor vapor feedbacks, that make climate change so potentially costly.

Re: What's Really Warming the World?

#335

Post by JoeAltmaier »

Zuider wrote: post #330
tosseraccount wrote: post #255

Earlier quoted context omitted.

Did any models predict the "global warming hiatus" ?

Hans von Storch, professor at the Meteorological Institute of the University of Hamburg discussed this issue in a recent interview with Der Spiegel. He remarked that less than 2% of model runs reproduced the 'pause'. http://www.spiegel.de/international/world/interview-hans-von... SPIEGEL: Just since the turn of the millennium, humanity has emitted another 400 billion metric tons of CO2 into the atmosphere, yet temper…

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

Re: What's Really Warming the World?

#336

Post by birdsbolt »

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…

There's a lovely book called The Limits to Growth published in 1972, through the years authors have updated their book and their models (there's more than 20). It turned out that business-as-usual model extrapolated very well from '70s to '00s. So, even them modelling was fairly good.

Re: What's Really Warming the World?

#337

Post by merpnderp »

pcrh wrote: post #217
merpnderp wrote: post #189

Earlier quoted context omitted.

Why does everyone ignore the UAH and RSS troposphere data? It's the best data (by far the most accurate) we have on atmospheric temperature, and it shows no warming since 1996. http://images.remss.com/msu/msu_time_series.html I have a simple R script to find the trend if you want to see it yourself.

Climate science is not my area, so I wouldn't want to comment on details... The wiki article suggests that earlier discrepancies between tropospheric and ground measurements have been resolved. https://en.wikipedia.org/wiki/UAH_satellite_temperature_data...

That article doesn't offer much information about how the discrepancy was resolved. I do know it is wrong in saying that the RSS troposphere shows more warming than UAH since 1998, because RSS shows zero warming since 1998. Don't trust me, please look at the data yourself.

But the land temperature stations have a miasma of questionable adjustments hanging around them. The stations themselves are not often well situated for clean readings, and then when the data is adjusted for heat island effects, rural stations will be adjusted upwards far more than urban areas will be adjusted downwards. I can't imagine why rural stations would ever be adjusted upwards, except on a case by case basis. But either way, the confidence intervals become mere guesses. It's unconscionable to mix that data with the more scientifically rigorous satellite data.

There's no getting around that the UAH and RSS sets show little to no warming for nearly 2 decades (RSS is 19 years and 6 months, and UAH 6.0 [most references to UAH will be 5.6 which is outdated] lines up nearly perfectly with RSS).

[Edited for mobile grammar mistakes]

Re: What's Really Warming the World?

#338

Post by guscost »

paulhauggis wrote: post #241
paulhauggis wrote: post #113

Earlier quoted context omitted.

I also question how we know the difference between nature/cycles and man-made pollution. Here is a good example: https://en.wikipedia.org/wiki/Little_Ice_Age "Several causes have been proposed: cyclical lows in solar radiation, heightened volcanic activity, changes in the ocean circulation, an inherent variability in global climate, or decreases in the human population." It seems we don't even know how the little ice…

I bring up some simple questions and I am immediately silenced. I guess I didn't realize HN was anti-science and anti-intellectual.

Some advice: there is definitely an acceptable way to challenge the mainstream here, but I don't think you've succeeded at it. Since all of your points have appeared here before, my suggestion is not to make them all at once (which encourages people who disagree with you not to bother responding and just to downvote) but rather to pick one or two of the most relevant points and back them up with extreme detail, meaning more than a link to Wikipedia.

For example, if we're talking about the proxy studies, you can mention how central they are to the larger debate and then go into detail about the long history of problems like the short-centered PC analysis in at least one of the MBH papers, or Briffa's divergence problem, or more recently the all-but-retracted Marcott paper.

Or alternatively, respond to someone claiming that the skeptics are completely responsible for politicizing the subject by pointing out that since the alarmists are demanding all the change, action, new laws etc, there is a very significant burden of proof on their shoulders. Then say that claiming "the science is settled" so they can skip to the legislation is very much why the subject is so politicized today.

And unfortunately, no community can completely avoid politics and groupthink at all times. So if you see a large number of people who seem like they will violently disagree with any but the most tactful of arguments then you can always just let them have their echo chamber and move on.

Re: What's Really Warming the World?

#339

Post by rosser »

paulhauggis wrote: post #240
hackuser wrote: post #160

Earlier quoted context omitted.

> I also question how we know the difference between nature/cycles and man-made pollution. It's a great question, one which has occupied many scientists. It has been addressed in detail in the scientific research. See: https://news.ycombinator.com/item?id=9772353 > The problem is that it's too political now. Remember that's a well-documented, established technique often used by people who want to obstruct things; cre…

"IIRC, 97% of climate scientists believe it's happening and caused by humans" Okay, show me a study that has the details on which parts are human made and which parts are caused by nature (with numbers). I have never seen this anywhere and You would think if they actually knew, we would have seen it by now. This isn't that difficult and it doesn't really make any sense that humans are causing 100%. Especially with th…

Really? You're going to make some kind of "quality of science" comparison between anthropogenic climate change and geocentrism?

Re: What's Really Warming the World?

#340

Post by fredkbloggs »

chris_va wrote: post #208
fixermark wrote: post #158

Earlier quoted context omitted.

Extinction is unlikely, given the vast amount of energy we have at our disposal (even if that energy's consumption is making it hard to be a biological construct on this earth). No, the likely scenario is in some ways even sadder: the 1% will survive in carefully-cultivated bunkers by the thousands or tens of thousands, and the vast majority (along with an awful lot of the other life on the planet) will die. Extincti…

That is not a likely scenario. The projected net impact from global warming is on the ~$2T/year range. That is about 3% of GWP. We aren't talking the end of the species, just really stupid expensive mistakes.

> The projected net impact from global warming is on the ~$2T/year range.

Such projections obviously assume that the warming stops at some point. I don't really see any reason to believe it will, at least not as long as a significant number of humans remain. Whether enough humans will die off before the effect becomes self-sustaining is still TBD.

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