The President of the United States, George W. Bush, recently voiced his opinions on the science of climate change:
We — first of all, there is — the globe is warming. The fundamental debate: Is it manmade or natural. Put that aside.
The first part is the silver lining: despite receiving novelist Michael Crichton in the White House recently, Bush obviously has not bought his theory that the globe is in fact not warming. Crichton is one of the last trend sceptics who deny the warming trend is real.
Rather, Bush adopts an attribution sceptic position: warming yes, but is it caused by humans? This position is equally out of step with science, where the debate over this question has also now been settled.
Data show that carbon dioxide levels are rising, they are now 30% higher than at any time during at least the past 650,000 years, and likely even the past several million years. This rise is caused entirely by human activities. This is also demonstrated beyond any reasonable doubt by data – for a start, we know how much CO2 we have emitted, and the observed rise is equal to 57% of this (the rest has been taken up by ocean and biosphere). That carbon dioxide acts as a greenhouse gas, trapping longwave radiation, is also a measured fact and well-established physics since the 19th Century. For a doubling of CO2 concentration, this amounts to a radiative forcing of 3.7 Watts per square meter, which in equilibrium would cause a warming of around 3 ºC (that’s the climate sensitivity discussed by us here). The rise of CO2, plus some other gases like methane, is already causing a forcing of 2.7 Watts per square meter. In equilibrium, you therefore expect a warming of 2 ºC based solely on the human-caused rise in greenhouse gas concentration. But there’s a time lag due to ocean heat uptake (“thermal intertia”), so that up to half the expected warming would still be in the pipeline and not here yet (this is shown by models and confirmed by oceanographic data, Hansen et al. 2005). That means: this rough calculation shows that the human-caused increase in greenhouse gases can explain at least 1 ºC of global warming. The observed warming is 0.8 ºC – this is less than what would be expected from greenhouse gases alone, because greenhouse gases are of course not the only factor that affects climate – there is a cooling effect by aerosols which counteracts part of the warming.
What about a “natural” explanation for the observed global warming? There is none. Indicators and measurements of solar activity show no increasing trend over the past 60 years. The orbital cycles, which cause the ice ages, would currently tend towards cooling, if anything. There is no remotely feasible alternative explanation for the observed warming published in the scientific literature. The “fundamental debate” postulated by Bush is a media phenomenon – to use the words of ABC News, a “con job” by special interest groups. It is not a debate that is ongoing in the scientific community. The numerous, often hair-raising arguments that have been brought forward as part of this “con job” have been thoroughly refuted many times.
In summary, the following scientific findings can no longer credibly be argued to be in dispute:
(1) The observed large-scale warming of the atmosphere and ocean is an entirely expected, and in fact well-predicted, consequence of the human-caused accumulation of greenhouse gases in the atmosphere.
(2) There is no other reasonable scientific explanation for the observed warming.
Bush would be more informed if he listened to what his close ally British Prime Minister Tony Blair has to say about the topic, or perhaps (why not try science?) the scientific Academies.
re: 43 if interested, see also 75,78 at:
https://www.realclimate.org/index.php/archives/2006/03/those-pesky-scientific-facts/
You are reading way too much into his one sentence off the cuff remark. You know that there’s still debate as to how much of the warming to date is anthropogenic (50-130% or thereabouts) and how much is natural (-30 to 50% or thereabouts seems to be the consensus).
I think he was merely trying to allude to that and got his meaning mangled a bit. I don’t think he believes (based on previous speeches) that there is still any real uncertainty as to whether anthropogenic greenhouse gas emissions have any warming effect on climate.
I agree with #52 in general, it is one off the cuff remark. Unfortunately, there is not much else to go on with this Whitehouse.
But, if a might digress, it is not clear to me that what Bush says is a reasonable indicator of what Bush believes. Further, knowing what Bush believes does not tell us what Bush cares about. Knowing what he cares about does not tell us exactly what he plans to do.
So the focus needs to be on what is actually happening, and as far as I can tell, actions on global warming from this administration are statistically indistinguishable from zero.
Eli Rabett:
It is intuitively obvious, even to the most casual of observers, what the group was trying to do in its post, as I explained in comment 36. I didn’t just fall off the cabbage truck. Did you?
And if you want to quote selectively from the 2001 NAS report, I can too. It also states that the link between human activities and the observed rise in global temperatures cannot be established “unequivocally”.
The larger point is that any recognition by anyone that there actually is a debate on climate change is anathema to the posters and commentators. But the fact that RealClimate exists is tantamount to acknowledging this debate. And what are those “Other Opinions” links all about, then, if not the debate? I welcome the discussions here and have learned a bit from this site, but I also take what I read here with a large grain of salt (as my next comment demonstrates).
Jim Redden:
Everyone is entitled to his own opinion, not to his own facts. If you look at the by now infamous Katrina video, you will see that the discussion concerned the possible “overtopping” of the levees, not their “breaching.” You don’t need to be an engineer to understand the difference. AP, which [mis]reported the original story, issued a correction stating that the President was not present when the issue of “breaching” levees was discussed. Not that you’ll care. But it important that this calumny not go unanswered.
Saint, if you must rely on “it is intuitively obvious”, then you clearly have no evidence of your intuition. I see no reason to accept your statment, and would recommend the same to everyone else. Basically, you came in blowing smoke, and when asked to show where the fire was, blew more smoke. This is as good an illustration of the gulf between political and scientific commentary. In the former case, “it is obvious to all” is common and accepted, even if it is not. In the second, you need to provide a reference.
You appear to think that because there is not “unequivocal” proof that a climate change is anthropic, that this issue is completely open. It is not. As the NAS (and IPCC) said five years ago, the evidence was strong, and the strength of the evidence has increased even further in the five years since. “unequivocal” proof is a level that is never even needed in courts, and certainly never found in the study of natural systems. For example, I would say that your failure to provide evidence for your intuition is very strong evidence that you are wrong, but it is not “unequivocal” proof.
To ALL other than Saint, please skip this OT reply unless you have some time to burn.
To Saint, my reference to Bush was in the context of a state of “readiness” as publicly asserted by Bush post Katrina–what was embarrassing about the vids for Bush was that he was warned, fairly severely in course: the word “ready” was not applicable–more like desperate need. It was reported that Bush did not ask one single question or make a comment during the videotaped briefing. I said nothing about levees breaching, nor topping. Speaking of the presidents saying nothing except ordering some cheeseburgers for lunch, there is a fine book:
For an inside look on George Bush administration, and some other players in the administration, one can look to the account of recused (fired) Treasurer, Paul O’Neil (The Price of Loyalty, Ron Suskind). While my derived and reasoned “opinions” vary far from those of O’Neil, the lack of diversity of thought and dialogue of this administration is notable from many accounts–thus, I take it as a factual recounting for now.
However, please keep the context of my example. I was merely trying to present the oft divergence of what is said by Bush, and what is done�.about what is said, and what is done (or not done).
On my primary source accounts, our president is notable for his personal touch, for when it’s hot, in bringing lemonade to the press corp, cupped in his own hands, to the reporters that follow him–and for also staying on message and trying his best to keep his mouth otherwise shut.
For that matter, the Katrina storm, the 3 day hurricane forecast was so spot-on it was shocking; indeed, there was a notable documentary a few years prior that duly warned anyone who wanted to be “warned”. Leading me to believe that government is no where to look when it goes bad, those who did need help, such as the ignorant, or the infirm, suffered.
The majority of those who voted him the Bush machine in, for the most part, have lost the most financially. I have heard some extolling the virtues of their tax cut, and at least that is rational. For the examining mind, Bush is bad news, even for the top 1% ultra rich who got a keep a little more during his 8 years–because the Earth will answer to itself. In that account, we have all lost.
Eli Rabett:
First, I stand by what I wrote – the evidence is in the original post. Anyone unfamiliar with the issue who read the group’s post would come away thinking that the President has denied that the growth in carbon dioxide concentrations was related to human activities. Otherwise why set up the straw man? I took the writers to task for leaving this false impression (among others). Despite your rather clumsy efforts at misdirection, you haven’t been able to counter my argument that the group’s post was unfair. Because you can’t.
Second, if you believe all of what appears on RealClimate passes for “scientific commentary”, then you really did just fall off the cabbage truck.
Third, you jump to conclusions. I am satisfied that human activities are responsible for at least some of the observed warming. But I’m open to opposing points of view, and I have a healthy respect for the uncertainties looking forward, which is apparently more than can be said for you (unequivocally!).
You really do need to get out of the echo chamber. The din in there must be awful.
[Response: I’ll make one final contribution, and then we can go back to more interesting topics. The text above was simply explaining why the attribution of climate change to human activities is now very strong – the first part is that the changes in atmospheric composition are unequivocally human-related, and the second is that our predictions of what those changes would produce are in fact very close to that observed. Mentioning both parts is simply dotting the ‘i’ of the argument, it is not a “strawman”. To all on this thread – please turn down the level of the rhetoric. -gavin]
It stil amazes me that people can think there is a worldwide conspiracy of climate scientists concocting alarming results to ensure a continued supply of funding. I think this slashdot commentary sums up the situation more accurately.
I mean seriously, if climate scientists were in it for the money, they would be in medical science, biotech or IT…
Gavin,
there’s a big difference between claiming that a majority of the change to date may possibly be natural (ie at least 0.2C out of the 0.4-0.8C to date) and rejecting the link between greenhouse gases and warming.
You wrote about climate sensititvity just recently. If a doubling of CO2 gives 1.5 to 4.5 C, presumably an extra 100 PPM gives 0.3-0.9 C or thereabouts, and that would allow the warming to date to consist of 0.32 C natural warming and 0.31 C anthropogenic warming.
That’s what I take away from the IPCC summary. Warming to date isn’t yet sufficiently large that we can exclude with greater than 90% probability the possibility that at least 50% of the warming to date is due to natural causes, but this is entirely consistent with claiming that the sensitivity to doubled CO2 is 1.5 to 4.5 C with at least 90% probability.
The main way I think this whole question matters (how much is anthropogenic to date) is that it is related to the question of how large climate sensitivity is. Greater than 50% being natural to date would indicate that climate sensitivity had to be much closer to 1.5 C than 4.5C.
In my limitless partisan optimism I’d even like to think that that is probably what Bush was really trying to allude to.
Coby,
if you look beyond the rhetoric and as you suggest at action the differences between countries and administrations don’t seem all that large to me. Clinton for example did not raise gasoline taxes or CAFE standards in his 8 years in office, US wind power was virtually static for most of the 90’s, while it’s gone from 2 GW to 10 GW between 2000 and now.
I know that Blair talks about climate change in fairly strong language, but that hasn’t gotten Labour to say reinstate the fuel price escalator abandonned in 2000.
It’s also quite difficult to work out how much CO2 emissions reductions are currently valued at. Subsidies for wind say or ethanol are not just given to reduce CO2 emissions. Taxes on petrol are there to raise revenue for the state, to reduce congestion and to cut carbon dioxide emissions. These different objectives are difficult to disentangle. I therefore find it difficult to objectively quantify how much the current US administration is willing to pay per tonne of C compared to say the current Labour government in the UK.
re 45. Michael wrote … What we need to be discussing here, other than pure science, is how to get out of this mess.
I made reference to a proposal called Conserve, NOW! (CN) : Reducing Greenhouse Gas Emissions and Other Environmental Costs:
http://groups.yahoo.com/group/ConserveNOW/message/30
in comment 43. of incurious-george:
https://www.realclimate.org/index.php/archives/2006/04/incurious-george/#comment-10744
I think the author (Michael Neuman) would appreciate comments on the CN proposal. I would pass along any comments to him if he isn’t following these RC discussions.
Heiko,
Far be it for me to take away any of your optimism, limitless though it may be! ;)
The Clinton administration is a long time ago in terms of the state of climate science and so what he did or did not do is remarkably irrelevant (even ignoring the antagonistic Congress and Senate that may not have facilitated any initiatives if he had tried). That said, I don’t particularily believe that a fully democrate gov’t today would be all that different except for rhetoric.
It doesn’t matter. This is not a partisan issue at all. Perhaps how to deal with it is, but facts are facts, they are not liberal or conservative. The science is conclusive, the situation is urgent. Do you have a leader in the Whitehouse or not?
I don’t agree that signing up to Kyoto and missing your targets is no better than thumbing your nose at it for explicitly self interested (though short sighted) reasons. (“the american way of life is not negotiable”, “we will not sacrifice a single american job”)
Explicitly and publically acknowledging the problem and its urgency is the essential first step.
Coby,
while intentions can be good, the net effect of missing your targets is the same as not even trying. Remember only we care about intentions, physically the same thing has occured. Perhaps it should occur to you that the countries that signed up and missed their targets did so intentionally to keep the net economic damage down, and yet agreed to it publicly for good PR reasons and to get good press? What is the fundamental differance?
Do any of you grow your own vegetables? Do you unse a greenhouse?
I like the typology of trend versus attribution skeptic. But is skeptic a proper term in this case? Skepticism, as associated with a scientific way of thinking, keeps an open mind and looks to falsify claims, in this case neither class of skeptics appears to be doing that. Instead, perhaps they could be more aptly dubbed “deniers.” Also, can the typology be extended. In this case, the term skeptic might more accurately apply to scientists or others who still challenge the link of climate change to certain impacts such as hurricanes? “Manifestation skeptics.”
Matt Nisbet:
The warming trend itself is a manifestation of AGW. Perhaps ‘Manifestaton skeptic’ is too broad. Perhaps ‘Impact skeptic’?
Re 64, 65:
I disagree with a ‘skeptic’ label. I think ‘denialist’ is a better descriptor. If you look carefully at the language in a typical comment, the exhibited behavior is denial, not skepticism.
Best,
D
Its not denialism so much as an over-reliance on statistics. You would not expect to be able to discern much if any human-caused warming in the stats. Because CO2-based warming is going to add Joules to the system, mostly be retaining more heat where the air is dry or where it would otherwise be dry.
So since CO2-based warming is small but cumulative it:
(a) Will not show up much if at all in the stats
(b) Could still be incredibly powerful over the very long haul.
They are merely being honest in terms of their interpretation of the statistics. But they have it wrong since the development of simple competing models and apriori reasoning should precede the interpretation of the statistics.
CO2-Lord Of Creation:
What in the world are you talking about? What “stats”? What is so hard to see in this:
http://en.wikipedia.org/wiki/Image:2000_Year_Temperature_Comparison.png
We were talking about the HUMAN-INDUCED component of that warming that you see in the graphs Coby. The wiki graphs purport to show only actual warming and do not presume to filter out that which is human-induced. This is where you have come off the beam.
You shouldn’t in any case be quoting wiki for matters that have become contentious. Once it becomes a leftist cause then they will lock down the subject.
My position is that the human component is very small BUT CUMULATIVE (up to a point). The cumulative part is the most important issue. And something that our side often misses.
Dano:
Matt outlined in #63 that he thinks those who dispute the trend and attribution evidence are better termed ‘deniers’. I have agreed with this notion for some time now – except I’ve used the term ‘denialist’, as you have.
Matt’s term ‘Manifestation skeptics’ and my alternate suggestion ‘Impact skeptics’ was intended to apply to those ‘… who still challenge the link of climate change to certain impacts such as hurricanes’
Dano, do you think the evidence for specific impacts of AGW, such as increased hurricane intensity, is so solid that those who dispute it ought to be termed ‘denialist’?
For now, I think the term ‘denialist’ should be reserved for those who deny the warming trend, the attribution, or that AGW is more likely to be dangerous than not.
Appologies if I have misframed Matt …
I don’t accept your rejection of the wiki link as it is clearly referenced and not a scientificaly controversial trend. See NOAA as well.
As for attribution, with no anthropogenic forcings we would have seen no general trend over the last century.