What are you talking about? I admit that I did not know about Milankovitch cycles until yesterday. I don’t claim to understand what causes ice ages. I don’t claim to understand what caused the Medieval Warm Period. And I don’t claim to understand what caused temperatures to increase this century.
If you really understand these things well, then you need to be able to answer challenging questions about them. If you dodge the questions, it suggests that you don’t understand things as well as you claim to.
Well, your questions often seem to be irrelevant word games. The important point of the scientific understanding of those cycles is the conclusion that the climate sensitivity is about 3 C for the radiative forcing produced by a doubling of CO2 levels. You can refer to this as Lex Luther overwhelming Superman for all I care. The words don’t matter (although some descriptive language is better than others, clearly, in communicating what is going on)…What matters is the mathematics and science.
I haven’t read any of the 60+ responses that have occured since this post; if I’m repeating something someone else said or addressing points you’ve retracted, I apologize, and if I’m saying something that contradicts someone else, I’ll address the contradiction as I move through the thread.
The calculation in post #10 is a detailed version of the conclusion posted in post #1. In post #1, I stated that the calculated blackbody temperature of the Earth is 248K and its actual temperature is 287K. Post #10 is the calculation of the first part.
The chart you provided has nothing to do with the calculation you posted. As a matter of fact, you are now citing a proxy CO[sub]2[/sub] record (despite your insistence on first-principle calculations only) to try and contest a bona fide first-principle calculation. If you accept the calculation, then you accept the fact that CO[sub]2[/sub] is competent to affect the changes we see.
What’s so confusing about this picture is why you think this would be evidence in your favor.
(1) The CO[sub]2[/sub] record here is proxy data. I’m not exactly sure what the proxy is, but considering they didn’t know about atoms in 1880, I’m pretty sure they weren’t measuring CO[sub]2[/sub].
(2) It’s unsurprising that CO[sub]2[/sub] doesn’t track exactly with temperature. As you’re so quick to point out, there are plenty of natural cycles in the temperature record, and as the IPCC has pointed out (which, might I helpfully add, is a great reason to actually read the report), the anthropogenic effect is probably only in the back half of the century (which your graph suggests).
Perhaps; re-phrase your point using standard climatological definitions and the explanation process is going to be easier.
If there are different CO[sub]2[/sub] increases, why would you expect the climatic change to remain constant? Each model has the same response to CO[sub]2[/sub] per unit increase. That is, if we knew exactly how much CO[sub]2[/sub] we would be emitting in 2050 (an economic, not a climatological, question), then we could predict with much smaller error bars what the climatological response would be.
The differences that you see between the SRES scenarios, then, represents economic uncertainty; the variation within a SRES scenario the climatological uncertainty.
What makes you think your specific example applies to this situation, then?
I guess you’re right. In accounting and perhaps a few other fields, you can. Comparing economic growth to climatological damage is not one of them.
You declined my simple request for proving you read the linked citations; I’m not going to spend time finding and quoting the relevant passages for you. The offer is open - at any point when I see evidence that you’ve actually clicked on those links and absorbed a little bit about what scientists have said, I’d be more than happy to quote you exact passages.
Because the thread is specifically about answering question in order.
I don’t disagree you’d be happy to cease discussion in this thread, since you don’t really respond to any of the climatological points. This really goes back to the question of how you’re going to argue the economics of something when you don’t know how it works.
You have yet to answer the questions posed to you in a previous post:
Even if science were politicized, you’d have a hard time explaining away the NAS support of the IPCC. As I’ve pointed out but it’s worth repeating …
(1) The NAS was created prior to industrialization, 30 years before the first mention of global warming, 120 years before the Vostok ice core was pulled and global warming research really began, and 140 years before the IPCC’s Third Assessment Report.
(2) The NAS, although appointed by Lincoln, has propagated itself without any political influences for 140 years, and has been selective of the top U.S. scientists on the basis of their scientific prowess alone.
(3) The NAS was asked by a Republican-dominated Congress and President; and funded by a Republican-dominated Congress.
(4) None of the NAS’s recommendations were adopted by Congress or championed by the President.
It’s really hard to make a case that the NAS report is politicized in any way.
I agree in principle - and challenge you to think about such “new evidence” and “new theories”.
You’ve cited two Senate reports, two mainstream media articles, and a blog as “evidence”. Are you seriously saying that these are less politicized than the NAS report?
You’ve also cited new theories - except that no other theory adequately explains the observed data. Let’s say, for instance, that anthropogenic gases are not causing warming. In that case, we have warming which greatly outweighs the observed causes. In essence, you are asked to choose between the following:
(A) The Earth is warming, humans are increasing GHG’s, the effect of GHG’s is 12x more powerful than observed natural factors, and the difference between natural factors alone and observations is exactly the magnitude of anthropogenic factors.
(B) The Earth is warming, humans are increasing GHG’s, but the two are totally uncorrelated. We can’t explain why the Earth is warming so much, but we’re sure that this is due to as-yet undiscovered natural factors.
The latter does not constitute a scientific theory. It fails to explain the observed data.
Now, if global warming skeptics were to actually come up with a valid theory - one that explicitly explains all the observed data and makes testable predictions - I would be happy to consider it.
Contrary to popular belief, science journals publish contradictory information all the time. My favorite was a series of back-to-back Nature articles from 2004, the first which argued Voyager 2 had passed the heliopause, and the second of which argued it hadn’t. Both sides had ample evidence in their favor; the decisive experiment couldn’t be run because the machine had been broken down.
Let me put it simply: how do you know that a Medival Warming Period existed at all?
Your answer would be that the proxy temperature data from ice cores and tree rings shows it - without such data, we really have no clue what temperatures were like prior to 1880.
Okay, so the question is whether the CO[sub]2[/sub] in the atmosphere is the same CO[sub]2[/sub] that we’ve been emitting. And this question has a very clever answer - how do we tell where the CO[sub]2[/sub] came from?
The answer is isotopic labeling. Plants prefer [sup]12[/sup]C (carbon-12) over [sup]13[/sup]C. In our atmosphere, present-day plants readily exchange both with the atmosphere, so that there is an equilibrium value. However, in old plant matter (fossil fuels), there’s an unusually low concentration of [sup]13[/sup]C because it has not exchanged with the atmosphere for a long time.
We can tell whether burning fossil fuels actually causes the increase because we can observe the concentration of [sup]13[/sup]C drop as CO[sub]2[/sub] increases.
I’ll try and restate what we know; then, I’ll let you respond as to whether you think this constitutes a proof or not.
(1) The CO[sub]2[/sub] that we’ve emitted is capable of causing the temperature increase (the first-principle calculations I’ve posted to brazil84).
(2) The amount CO[sub]2[/sub] that we’ve emitted “pushes” (radiative forcing) the temperature 12x harder than natural forces that we know about.
(3) When you run simulations of past temperature and omit greenhouse gas forcing, you cannot reconcile the data (there is a large gap). When you include it, you see a good match.
Without creating a duplicate Earth and selectively increasing the CO[sub]2[/sub] on one (which would constitute a formal “proof” of causality), what would you like to see before you say that this is more than correlation?
The absolute temperature doesn’t matter. We could be colder than the MWP and still be looking at AGW. AGW is about the rate at which temperatures are increasing - the Earth could be getting colder, but AGW could slow it down; likewise, the Earth could be getting warming, but AGW could accelerate it.
Scientists believe the latter is the case - the Earth would otherwise be slowly warming without us, but that with us, this warming is much faster.
This may be repetitive, but it’s worth repeating - even if temperatures were getting colder, anthropogenic global warming might still be true! In this case, we’d be cheering global warming, but that eloquently explains why the questions I listed have to be considered in order.
What scientists are sure about is that the world is getting warmer and that we’re a partial, if not the major, cause. Now the next question is equally important - will global warming actually hurt us? The answer is far less certain than the first two questions.
(2) Nice try at playing us off one another, but it’s futile. Linear or logarithmic, the difference would mean the difference between you being absolutely wrong and just wrong.
As claimed by Lindzen, the difference between linear and logarithmic is a factor of 3. If the linear assumption is correct, the anticipated warming from GHG is +0.7[sup]o[/sup]C. If the logarithmic is correct, the warming is only +0.2[sup]o[/sup]C.
Either way, if you read the IPCC report, you’ll note that only “most” of the warming in the back half of the century is attributed to anthropogenic causes - half (the bottom end of “most”) of the half of the observed +0.8[sup]o[/sup]C warming is +0.2[sup]o[/sup]C. In other words, if Lindzen is right, then the IPCC is dead right. If Lindzen is wrong, the IPCC is actually underestimating the effect of CO[sub]2[/sub].
Not exactly. The data you’re probably talking about is the Vostok ice core data, which shows a strong correlation of CO[sub]2[/sub], dust, and temperature.
That sometimes CO[sub]2[/sub] level rises precede temperature rises and sometimes lag has been a subject of debate (which is probably what you’re thinking of).
We’ll answer the question you asked first.
The answer is simple - a variety of things. The IPCC reports, if you bothered to read them, would tell you that many things affect temperature - both positively and negatively. Dust and particulates (both from natural sources such as volcanic eruptions and meteorite impacts) cool the Earth, for instance. In the past, it’s quite likely that these, along with orbital factors, caused the Earth to cool and warm (Milkanovitch cycles).
Now, let’s answer the more interesting question you didn’t ask.
A good question with a technical answer. Let’s explain how this works first.
Oceans work as large resevoirs of CO[sub]2[/sub]. They absorb and emit CO[sub]2[/sub] and act as buffers. The solubility of CO[sub]2[/sub] is lower at higher temperatures - so when temperatures rise, the oceans can release CO[sub]2[/sub] (which is why we sometimes see lagging). On the other hand, as shown before, CO[sub]2[/sub] can cause temperatures to increase (which is why we sometimes see leading).
So the big question is which scenario are we seeing right now?
To answer this, you look at the oceans - if it’s the first scenario, we would expect the oceans to be releasing CO[sub]2[/sub]. But they’re not. The oceans are taking up a sizable chunk of the CO[sub]2[/sub] that we’re emitting.
I don’t understand what you mean by dominating. But, let me answer the question this way: When CO2 levels are remaining fairly constant while the Milankovitch orbital cycles are causing the sunlight distribution to change (and thus causing ice sheets to grow or shrink) then, yes, the forcing due to the latter can be larger than the forcing due to the former. In any given situation, you have to compare the radiative forcings of each thing that is happening.
Maybe this isn’t the point that you’re talking about directly, but it’s a big point in general. That you have no idea what the models predict is an enormous disadvantage in a rational debate - especially since the models, their results, and scientifically agreed interpretation of those results has been linked to you.
The point is not only that the model data is known, but also that it is known to you.
This thread is not about some tree-dwelling environut telling you that the world is coming to an end. This is about three scientists telling you this is what scientists think, and then linking you to the data which says so while you ignore the evidence and repeatedly call for citations already given.
Yes or no: The calculation in post #10 contains no variable that corresponds to CO2.
Simple yes or no question.
Where do I insist on first-principle calculations only?
Anyway . . .
yes or no: There have been periods in the last 130 years when CO2 levels rose and average temperatures fell.
Simple yes or no question.
In that case, your simple calculation doesn’t mean much. Indeed, when jshore read my response to your post, he or she apparently thought I had constructed a strawman.
I already defined my terms. If you have a specific question, I will try to answer it.
Who says I do?
And if we knew exactly how climate responds to CO2, we could predict with much smaller error bars what the future climate will be like. Right?
Because in either situation, you have a net quantity. We know that there has been a net increase in human well being in the last 100 years. It’s as simple as that.
I don’t see any quotes.
And I’m not going to spend my time doing your research for you. If you claim that some authority supports your position, simply quote that authority and link to it. It’s as simple as that.
Dude, what are you talking about? I offered to stop talking about economic growth at your request and even though you are the one who brought the issue up.
If you want to present something concrete, as opposed to waving your hands around the IPCC reports, I will attempt to respond to your points. (To the extent that you have fairly characterized my position.)
Dude, did you read jshore’s post? I was responding to you, and he or she thought I had constructed a strawman. Among other things, he or she asked where I got the 5% figure from – I told him or her it came from you.
0.2C over what time period?
What exactly is the claim I made that you feel is incorrect?
Yes. The explanations are in each of the three reports linked at the beginning - IPCC 3AR, NAS CCR, and IPCC 4AR; furthermore, I’ve alluded to the reasons in my last flurry of posts. If you read each of the posts I made today and take five minutes of critical thinking, you will determine for yourself why this is the case and why it actually supports, rather than detracts from, the IPCC reports.
Another veiled attempt to try and play your opponents off of one another?
Here’s a simple yes or no question for you: Do you accept my first order calculation as proof that CO[sub]2[/sub] is competent to affect the temperature changes we see?
I’ve already posted my specific questions. You categorize “sensitive” and “non-sensitive” scenarios based on the temperature ranges they give, and then you claim that the temperature ranges are solely a function of sensitivity - a conclusion which is obvious because you’re claiming correlation to a self-categorized variable. Simple question: what variable is the independent variable, and what variable is the dependent variable in your analysis?
You do.
If you agree that models predict different amounts of CO[sub]2[/sub] increases, why wouldn’t you expect different responses? If the different models predict different amounts of CO[sub]2[/sub] increases, then your classification of the models as “sensitive” versus “non-sensitive” simply reflect the differences in projected CO[sub]2[/sub], not differential response to per-unit changes.
No, it’s not.
(1) There is still an unaddressed inconsistency in your argument. If you don’t accept that global warming causes net harm, then you concede the possibility that global warming, not economics, has caused the increase in human well-being.
(2) Even if you resolve the inconsistency in (1), you still have to point out why you’d think that economics is winning by a large margin - I could claim that global warming in the 20th century has reduced our GDP by 99%, and that had global warming not occurred, we would be 100x richer today than we currently are.
(3) Once you finish explaining (2), then you have to explain why you would dismiss efforts to curb global warming - after all, even if global warming had a small effect, if scientists predicted it would be 10x worse in the 21st century (i.e. +10[sup]o[/sup]C and that the effects were exponential (i.e. 1000x worse than seen), then a 10-fold increase in GDP may not be enough to offset the problem.
What you are claiming is that without any knowledge of how much the Earth has warmed in the past 100 years (since you criticize the instrumental temperature record in post #35), and without any knowledge of how much the Earth is expected to warm, and without any knowledge of how harmful such a warming would be, that a 10-fold increase in world GDP will clearly trump any of those effects.
That is a clearly indefensible position.
You have links in post #1 of this thread and then a chapter and section citation with an exact figure citation.
You are not doing my research for me - you are doing your research for yourself.
If only it were as simple as that!
In post #38 of the Economic Hockey Stick thread, you asked for quotes that showed the NAS supported the IPCC. In post #39 you were given 6 quotes. In post #40, you dismissed all six quotes with:
Simple yes or no question: Were the quoted passages exactly what you requested?
I have presented top-level reviews of peer-reviewed data (the IPCC and NAS reports) and then I have cited you the exact subchapter and exact graphs that support my position. Then I supplemented that with the first-principle calculations you requested. You have yet to respond in any factual way to any of the data presented.
You have also taken up positions factually contrary to the IPCC and NAS and then refused to answer direct questions about the basis on which you do so.
Should there ever be a question about which direct questions those may be …
Dude, you do realize that, even if jshore and I disagreed with each other, that wouldn’t make you less wrong? jshore is pointing out that the IPCC is right; I’m pointing out that the first-order calculations are more than right.
And incidentally, jshore is right. Most scientists believe CO[sub]2[/sub] is responsible for much more than 5% of the greenhouse effect (Wikipedia says 9-26%); however, 5% is the commonly cited figure by Richard Lindzen and other global warming deniers. Rather than launch into a big discussion about which number is correct, I chose the lowest accepted value to show that even with all Lindzen’s objections factored in, the IPCC is still right.
The time period is given in my post. Read it more carefully.
This one:
Simple A/B question: So you’re arguing that you’ve been proven wrong, or that you’ve been proven wrong by two different independent methods? Either I’ve proved you wrong once or twice; as far as I’m concerned, the question is settled.
As I pointed out before, I’d be more than happy to quote the sources if I felt there was a greater than 0% chance you’d read it. You’ve dismissed, without evidence, the other quotes I’ve given.
You’re not my research assistant - you’re your own research assistant. If you can’t find the citations I’ve listed, or if you don’t have the time to look them all up, then simply look one up and make an educated comment about it; I will then have some evidence that you read >0% of my quotations, and have already promised to post the rest of the quotes for you.
This is not an exercise to send you on a wild goose chase - it took a non-trivial time to look up the subchapter references and graph references to begin with. I’ve met you more than halfway, all you have to do is find click on a link and find figure 2-7 in chapter 2-2. What’s so hard about that?
Thank you for admitting that. So much for your “detailed version”
Are you kidding? That’s not an insistence on a first principle calculation. I’m simply pointing out the implausibility of your claim.
And that shows that your simple calculation doesn’t mean much.
If jshore states or implies that you are wrong, is there any reason I should not mention it?
Affect? There’s no need to do a calculation to conclude that CO2 can affect temperature changes.
Not at all. If that’s what you think I did, then you totally missed the point.
Why not answer my earlier question:
And if we knew exactly how climate responds to CO2, we could predict with much smaller error bars what the future climate will be like. Right?
CO2 output and climate response to CO2 are independent. Temperature is dependant. And it’s not an analysis, I’m just re-grouping the analyses you alluded to.
No, you’ve got it 100% backwards. I would expect the climate change to be different for different CO2 changes. (Assuming the same sensitivity to CO2.)
Please try reading what I post a little more carefully before you hit the reply button.
Where did I say otherwise? And please read my posts before you quote me.
Nonsense. Human well being has clearly been improved by increases in wealth and technology. Vaccines; better communication; etc.
Look at my economic growth thread, in particular the cites about drops in death due to extreme weather.
Remotely possible, but the difference in effects is so profound that the warmers carry a huge burden.
Lol. Whatever. I’m not going to spend time looking for quotes that may or may not support your position. That’s your job.
No, and that’s why I prefer quotes. It’s very easy to just wave one’s hands, point to some long document, and claim it supports one’s position.
Haha. Just like in my temperature thread when you stated thus:
I went through the trouble of looking up your graphs and they didn’t support your position. You were wrong and you never even acknowledged it. You just disappeared from the thread.
Most scientists believe CO[sub]2[/sub] is responsible for much more than 5% of the greenhouse effect (Wikipedia says 9-26%); however, 5% is the commonly cited figure by Richard Lindzen and other global warming deniers. Rather than launch into a big discussion about which number is correct, I chose the lowest accepted value to show that even with all Lindzen’s objections factored in, the IPCC is still right.