What's Really Warming the World? • Hacker News Board

Re: What's Really Warming the World?

#221

Post by GlueChemist » Wed, Jun 24, 2015, 4:45 PM UTC

possibilistic wrote: post #176

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…

Do you happen to have this one to five pages of QM equations somewhere as reference? I would be very interested in reading that.

I believe he is referring to the 'postulates of quantum mechanics', you can find several formats from a quick google search.

Dirac, 1929: "The fundamental laws necessary for the mathematical treatment of a large part of physics, and the whole of chemistry are thus completely known, and the difficulty lies only in the fact that application of these laws leads to equations that are too complex to be solved."

Re: What's Really Warming the World?

#222

Post by ska » Wed, Jun 24, 2015, 4:45 PM UTC

dnautics wrote: post #132

fexl wrote: post #72

Earlier quoted context omitted.

Are there any data on water vapor concentrations? I ask that because I have read that the contribution of water vapor to the greenhouse effect is perhaps two to four times greater than CO2.

Not only that, all greenhouse models require a 'water feedback loop'. Of course there are plenty of anthropogenic water emissions to go about. When you irrigate, you are effectively throwing water into the air - by increasing the surface area of water evaporation through plant transpiration networks. I have never seen anyone talk about this alternative hypothesis. A disclaimer - I am all for reducing CO2 emissions st…

does 2.5.6 from http://www.ipcc.ch/pdf/assessment-report/ar4/wg1/ar4-wg1-cha... address this adequately?

(I was curious from your comment, but only spent a minute looking)

Re: What's Really Warming the World?

#223

Post by thadd » Wed, Jun 24, 2015, 4:45 PM UTC

My only problem is that the planet is over 4 billion years old and as this shows, we've been collecting climate data for a little over 100 years. The natural skeptic in me isn't ok with establishing a trend based on 1/40,000,000 of the available data, the sample size is simply too small. Am I completely off-base with this?

Re: What's Really Warming the World?

#224

Post by 7Z7 » Wed, Jun 24, 2015, 4:46 PM UTC

curiousgeorgio wrote: post #115

Brakenshire wrote: post #111

Earlier quoted context omitted.

> it doesn't prove one way or another whether the cause of the rise in greenhouse gasses is manmade. Does anyone seriously doubt that rises in CO2 are not principally driven by human activity? I have never even seen that as a talking point.

Does the popularity of a doubt or idea even matter here when we're supposed to be discussing science?

Brakenshire didn't question the popularity of the topic, rather whether it had been convincingly postulated by anyone worth mentioning.

Re: What's Really Warming the World?

#225

Post by Shivetya » Wed, Jun 24, 2015, 4:46 PM UTC

tocf wrote: post #201

Shivetya wrote: post #20

CO2 is not strictly human emissions and to imply so is so dishonest is ridiculous. of course any gross simplification of the environment as done in this presentation is explicitly to deliver a message decided before the numbers were assembled. the primary co2 process is ocean to atmosphere exchange, the earth to atmosphere, and then to mammals respiratory activity. So then you get down to how much CO2 is man pumping…

> CO2 is not strictly human emissions and to imply so is so dishonest is ridiculous. That was never implied. In fact, they made a point of comparing human driven emissions (which includes things like transportation and agriculture) to natural sources (eg volcanoes). > the primary co2 process is ocean to atmosphere exchange, the earth to atmosphere, and then to mammals respiratory activity Well, you're missing some st…

yet today we also have articles noting that "natural cooling" of the sun will not be sufficient to offset other sources of warming, the same sun this article here dismisses as having any real influence.

this is the problem with the current climate science industry and don't mistake for a moment, this is an industry with great profits at stake for both government researchers and private industries.

They never have a consistent message. We had dire declarations since the turn of the century and many lined up behind those. This particular article is a gross simplification that attempts to dismiss common arguments against by associating them with frivolous arguments. It seeks to minimize without informing. Its pretty but not accurate. There are hundreds if not thousands of scientists who all apparently have different views on what contributes, how much it does, and so on.

So yeah the climate is changing, but it has been doing so forever and there have been historically proven changes greater that what we are seeing now and with man here as well.

Simply put, we don't know all the variables and those who declare we do are more ignorant than those who deny any effect.

Re: What's Really Warming the World?

#226

Post by paulhauggis » Wed, Jun 24, 2015, 4:46 PM UTC

paulhauggis wrote: post #113

macinjosh wrote: post #83

Please don't take this as a denial of climate change, it is an honest question. How do scientists learn the levels of ozone, aerosols, green house gases, and the other data points going so far back at a global scale? Is the data from before the latter half of the 20th century spotty? If so, why is it considered good enough to use in a context of scientific research where quality and correctness of data is paramount?

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.

Re: What's Really Warming the World?

#227

Post by jlebar » Wed, Jun 24, 2015, 4:47 PM UTC

posnet wrote: post #216

Does it bother anyone else that only the Global temperate has its axis labelled? What is the orbital wobble measuring? What is the volcano line measuring? Is that decreased forests or decreased land use? Should be be using more aerosols? Is that meant to be suns temperature or sun activity, or sun colour? I realise that the actual data is from reliable carefully measured models but it makes this illustration so point…

> What is the orbital wobble measuring? What is the volcano line measuring?

Read the bottom of the page; it explains that the colored lines measure the modeled expected impact from orbital wobble/whatever on climate. That is, all of the lines measure global temperature.

Re: What's Really Warming the World?

#228

Post by stillsut » Wed, Jun 24, 2015, 4:47 PM UTC

GHG seems to match Temperature quite well. But GHG is cut-off at the year 2000. I wonder if the closeness of the fit continues?

Also, what's up with the error bars around GHG's? Is there really that much uncertainty surrounding CO2 concentration in the atmosphere? I thought readings were accurate to ~1ppm where the trend is currently +3ppm/year so why are the observations (in the modern sensor era) uuncertain by about ~45ppm?

Re: What's Really Warming the World?

#229

Post by istvan__ » Wed, Jun 24, 2015, 4:48 PM UTC

istvan__ wrote: post #175

vlasev wrote: post #107

Earlier quoted context omitted.

So, where would you think the greenhouse gases came from?

Which one? https://en.wikipedia.org/wiki/Greenhouse_gas#Greenhouse_gase...

There is nothing ironic here, humans add more CO2 sources and kill the most CO2 sinks (forests) these activities would put any system off balance. People like to talk about how CO2 production is bad but they forget to mention that killing rainforest is equally bad.

Re: What's Really Warming the World?

#230

Post by Roodgorf » Wed, Jun 24, 2015, 4:49 PM UTC

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 effect is the reason why cities are warmer than their surrounding rural areas.

Anthropologically produced heat is certainly a contributor, but as the article itself says, I believe the majority of the difference is more accurately attributed to the large amount of concrete in cities which takes much longer to dissipate heat.