In the meantime, the most important message to carry away is that even though the NAS study nitpicks some of the details of the Mann study, they acknowledge that the “hockey stick” is real, real as in physical and historical, and is not merely an artifact from one potentially flawed reconstruction methodology. Like I said earlier, Mann is not the only person in the last decade who has attempted such a reconstruction, and he isn’t the only person who has found a significant recent break in the temperature record. The primary reason his work is the most cited of its kind is because it was one of the first, and the most well-known. That’s generally how citation works, for better or for worse. It isn’t limited to climate science.

I’m not sure what stance you think I was taking, I was just trying to point out that the NAS report did not, in fact, back Dr. Mann’s graph. However, you say:

As for criticisms, Mann himself acknowledged most of them as legitimate.

So it only took 7 years, a couple of congressional hearings and a NAS panel convened in his honor to admit it. Bully for him.

Actually, in this response from RealClimate to the NAS panel report(which I assume he had a hand in writing), it’s hard to see where he admits to much of anything. Do you have another reference?

As for criticisms, Mann himself acknowledged most of them as legitimate. A science as difficult as this naturally has room for improvement, and researchers will of course make errors. If Mann was arguing against the NAS for their criticisms, I think you would have a more solid stance here.

While I think the Bush White House is guilty as sin on a long long list of antiscience endeavors, global warming is probably the least likely place they will budge, given how much money is behind denying the reality of it.

Pres. Bush, in a speech in 2001:

First, we know the surface temperature of the earth is warming. It has risen by .6 degrees Celsius over the past 100 years. There was a warming trend from the 1890s to the 1940s. Cooling from the 1940s to the 1970s. And then sharply rising temperatures from the 1970s to today.

There is a natural greenhouse effect that contributes to warming. Greenhouse gases trap heat, and thus warm the earth because they prevent a significant proportion of infrared radiation from escaping into space. Concentration of greenhouse gases, especially CO2, have increased substantially since the beginning of the industrial revolution. And the National Academy of Sciences indicate that the increase is due in large part to human activity.

And at a press conference in 2005:

Listen, I recognize that the surface of the Earth is warmer and that an increase in greenhouse gases caused by humans is contributing to the problem.

You can argue that the Bush White House is not doing enough, or is doing the wrong thing, but I don’t think you can argue that they are denying the reality of global warming.

You mean the one backed by the National Academy of Sciences, perhaps the most august scientific body on the planet?

From the NAS report:

Based on the analyses presented in the original papers by Mann et al. and this newer supporting evidence, the committee finds it plausible that the Northern Hemisphere was warmer during the last few decades of the 20th century than during any comparable period over the preceding millennium.

Plausible? Hardly a ringing endorsement. If you read the full report, it actually endorses most of the criticisms of the Hockey stick graph.

You’ve suggested visiting RealClimate before – I check it daily. Will you visit Climate Audit ? I think a skeptic like you will appreciate what he has done there.

By the way, Mann isn’t the only climatologist in the world that constructed a temperature record and found an abnormally large recent warming. It was one of the firsts, so that’s why all the big guns are aimed at it. Just so you know.

No serious scientists backing global warming denies that temperatures have changed rapidly in the past. Actually, it was paleoclimatologists who discovered this fact. But the question is why is it changing today. Temperature doesn’t change for no reason. Nothing happens for no reason. You should know that. And to start off, take a look at the reconstructed atmospheric carbon concentration record. During the past million years, there is no evidence that carbon concentration rose much beyond 300ppm. As of this year, it sits at 380ppm, much higher than found anywhere in the history of modern ice ages. I think you’ll find it a hard argument to claim that the corresponding carbon concentration increase is “ordinary” as well.

Global mean temperature does not tell the entire story. Global mean temperature is a useful gauge of climate change, but at the end of the day, it is only one number. You must look elsewhere to learn more.

Second, on the more important topic of global warming, I have to admit that I have been “on the fence” for a long while about the CO2 issue. I believe that I am in the majority of most Americans with this perception. As many others have said, a current global warming trend is very apparent. However, for reasonably intelligent people like me, it is difficult to distinguish fact from embellishment. There have been many reports (most from gov’t agencies sponsored by US/EU/UN) that have clearly been made to look like the amount of warming occurring is greater than it actually is, which leads me to doubt these same reports predictions of future trends and the reported causality of these trends.

So. Being a reasonably intelligent person, I decided to research this topic on my own time. I have read many discussions/reports/articles/rants/ect. on science, environmental, political, and economical blogs & websites. But everywhere I go, the argument is always the same. Nobody on either side of the issue can convince with resounding evidence that human influence is or is not the direct cause of the current warming trend.

What is then wrong here? Everyone is focused on the problem. Not the Solution. First of all, what are the facts?

1. Global warming is occuring.
2. CO2 levels have risen.
3. The higher CO2 levels are most likely caused by humans, but not definitely.
4. The cause of the warming trend cannot be directly correlated to the higher CO2 levels.
5. Global warming may or may not be a bad thing. This is NOT certain.
6. Reducing our CO2 output cannot hurt the environment, and will most likely help.
7. Major changes in CO2 pollution could have severe economic impacts.

So what do we do? The only rational course is to assume that CO2 output needs to be reduced in order to minimize our impact on global warming trends. But we have to do it in a way that does not undermine the world economy.

When I realized this, I began looking for solutions. And I found very little realistic solutions being offered by scientists or politicians or environmentalists. Scientists and environmentalists are not economists, and politicians are money-grubbing….. Well. You know.

I was beginning to get worried that nobody was thinking about solutions when I found this great article written by Gregg Easterbrook, most known for his articles on the NFL. A sports writer, you say? Not really. He’s actually just a fan who writes a great column for espn.com. His main journalistic focus is in economy, politics, etc. Please. Read this column about solving CO2 polution. It may not be the final or only answer, but it will get you thinking about the solution. Not the problem.

http://www.brook.edu/views/papers/easterbrook/20060517.htm

I’m not trying to insult you or tell you how to run your websites, but please, influential and intelligent bloggers/debaters, start thinking about and talking about realistic solutions. It will only help your case. If you feel very strongly that we need to change as a society, then try to figure out HOW we can change. Stop arguing about inconclusive graphs and data and use your intelligence to fix the problem. Let’s try to have some optimism that we can change things, and that it will get better.

A lawsuit between several states and environmental groups vs. the Federal Government via the EPA, filed in federal court and appealed through the legal process first to the district court, and now to the Supreme Court, and somehow it isn’t appropriate for them to review? It is the Supreme Court’s mandate to interpret the law. If that interpretation has repercussions on the actions to be taken by the Executive or Legislative branches, that is a part of the process. They are being asked via the lawsuit to interpret the Clean Air Act with respect to what it tells the EPA it can and must do. Sounds exactly like a legal question the Supreme Court is supposed to address.

Steve S said:
>Putting aside my opinions on global warming, I still have a problem with this paragraph that Hansen defends (trying not to remove any of the context while keeping it short):

>Emphasis on extreme scenarios may have been appropriate at one time, when the public and decision-makers were relatively unaware of the global warming issue…
Now, however, the need is for demonstratably objective climate forcing scenarios consistent with what is realistic under current conditions…

>Can somebody explain that paragraph to me if I interpreted it the wrong way? It just seems to me like he is supportive of the poor PR tactics as long as it supports his viewpoint.

It sounds more to me like he is letting them off the hook for any past behavior in an attempt to redirect their current efforts. The whole “may have been appropriate” structure looks like a rhetorical device of allowing the person the possibility there was some justification for their action so as to seem reasonable enough for them to listen to you, rather than starting by calling them idiots and then trying to get them to agree with you. Consider the alternative:

“You flaming moron, what possible justification could you have for exaggerating the consequences and distorting the real conditions just to get attention? Please change your strategy.” Doesn’t sell as smoothly, does it? It’s called being diplomatic.

Here is a good reconstruciton of all the accepted global mean temperatures over a period of 1000 years and going back to the last glacial period.
http://en.wikipedia.org/wiki/Image:Holocene_Temperature_Variations.png
http://en.wikipedia.org/wiki/Image:1000_Year_Temperature_Comparison.png

Please note the ONLY temperature reconstruction that claims that temperatures are above the norm for either period is the discredited Mann graph.

http://www.telegraph.co.uk/news/graphics/2006/11/05/nwarm05.gif

Notice the key word Europe on the bottom graph. Despite what Europeans thought back then (and sometimes think today), Europe is not the center of the planet. “Global mean temperature” means just that: global mean. The warm period parts of Europe enjoyed during the medieval times was not a global event. That’s why the Medieval Warm Period signature is greatly reduced when the global average temperature for the same time period is calculated.

I rarely use TV for any information, and for science information hardly ever. I always try to mind the primary source. I’ve been fooled way too many times to believe any new that comes from the TV. My TV is used only for entertainment purposes only. (A good example of this misinformation can be found by looking up quotes attributed to either Al Gore or Dan Quayle. Most of their supposed quotes never happened or have been modified slightly to make them look dumb.)

You want to see how a credible global warming skeptic is treated in the atmospheric science field? Look up the Roger Pielke father-son team (http://sciencepolicy.colorado.edu/prometheus/). They are skeptical of many mainstream climate science claims, but they argue respectably and with significant rigor. They are taken seriously because they do much more than blow hot air and whine to the media and politicians, unlike certain other warming deniers. The claim that pro-global warming scientists are attempting to snuff out dissent is rubbish. It is fiction. Please don’t let a few talking heads on the boob tube fool you. Read the literature yourself if you don’t believe me.

Check the records: environmental groups gave Clinton very low scores and deservedly so.

All this debate reminds me of the archeological evidence of the severity of the environmental impact on the Easter Islanders. Being in a closed system, they did what all humans do, use the resources at their disposal to control their environment, and forget to look forward at the finite nature of their surroundings. There can only be so many trees to chop down, birds to eat, fish to catch, etc.
Earth is itself a closed system, and you cannot exploit the available resources and expect science to control the equilibrium. The problem with tipping the scales is that at some point, a positive feedback loop develops and it takes a very long time (and probably a large number of species’ extinctions) for equilibrium to re-establish. To all the human induced global warming doubters, I’d suggest you learn to appreciate cockroaches. Once a cascade reaction starts (say methane hydrates bubble out from the sea floor or the permafrost under Siberia), the only thing left of human inpact would be those very roaches surviving on the junk food in your cupboard.

I don’t want to give up my standard of living either; and I sincerely hope you are right. The evidence suggest otherwise.

Parts of his article are wrong. In the section where he writes about the 20% reduction in Earth Science funding, he makes some statements which are not true. There are plenty of ways that the infrastructure cost can be reduced. First, it is false to say that federal employees can not be fired. It is called a RIF (Reduction in Force). Second, people can be reassigned to other NASA centers. In Houston, several civil servants have come from Glenn in Ohio. Third, NASA could also do the forced retirement bit that it did during the Clinton years. (It wasn’t truly a forced retirement, but when you have the NASA adminstrator talking about RIFs, calling the workforce “too stale, male and pale” and then offering retirement bonuses and early outs, its basically a forced retirement). Third, don’t hire anyone new and let attrition take care of getting rid of people.

I also feel he was misleading when it comes to new missions. The STEREO mission just launched (CloudSat in April 06), two Earth mission are planned for launch in 07 (AIM and THEMIS), two are planned for launch in 08 ( Ocean Surface Topography Mission, Orbiting Carbon Observatory) and one for 09 (Aquarius). There are also a half dozen satellites in orbit right now that if the powers that be wanted to, could end funding for but haven’t.

If met James Hansen and this reduction topic came up, my comment to him would be welcome to my world, because the funding cuts that he’s seeing now are what I saw happen to manned space flight during the 1990′s under Clinton. That’s what happen when you get a new administration and the leadership decides that NASA needs a new direction. That’s what happened under Clinton, he took a new direction from Bush the elder’s plan. Personally, I think that both Clinton’s and Bush’s cuts are/were shortsited, because you get rid of the talented people and it takes a long time to get new people.

With regards to Bill Gray, his point and my point too is that if you’d don’t follow the status quo, with regards to global warming you don’t get federal funding. In my former life as researcher, lack of funds = death of project. IMO, that’s suppression.

A few points here. Let’s distinguish the facts
- It is a fact that global mean temperature has increased over the past 150 years with a noticable spike in the past 20-30 years
- It is a fact that the co2 concentration in the atmosphere has increased from about 300 ppm to 380 ppm during this time and the only logical cause is human activity and that future trends hold up this level will increase by about 10 ppm per decade.
- It is a fact that the current global mean temperature has not exceeded previous maximums over the past 1000 years, let alone the past million. Even the real climate site, which is not exactly an unbiased source, does not dispute that the vast majority of studies recognize this.
- It is also a fact that global temperature variations over the past several thousand years are comparable with recent variations. We can argue whether they are as sustained or can be attributed to specific causes or not but they exist in the temperature record.

Now we enter the realm of speculation as to the cause of the recent temperature increase and possible future trends.

Many see the temperature rise and the co2 rise during this period and make an assumption they must be related. I don’t dispute this is possible. I have yet to see a climate study that definatively makes this correlation. I’ve read many abstracts that speculate this point but nothing that proves it.

As for future trends, the climate models don’t take into account other factors over this period because there is not accurate data. Yes, there is some proxy data on solar activity, particulate matter from volcanic activity and ocean current oscillations but this is spotty and highly open to speculation. The only solid numbers that exist based on the known climate factors is the co2 levels and this is what the climate models are based nearly entirely on.

But no climate model exists that has accurately forecasted previous variations in climate over the past several decades, or serveral centuries. So how can we rely on these to predict future trends? Yes there are some climate models that claim to have made a correlation on a much shorter time period (previous 10-15 years), but even the proponents of these recognize that it will require another decade of data to validate the models.

Does it sound to you like he is condoning the use of scare tactics to attract attention to the issue of global warming? You can’t scare the world with outlandish claims and then tell them, “Just kidding about the 10C increase in global temperatures over the next 50 years. We have done some REAL calculations and the number is around 1C. The other number came up when we were testing the limits of our climate models.” Especially when you have already berated the world (specifically, the public and policy makers) for being ignorant on the issue of climate science. How can you expect them to understand your more probable numbers while you throw around much larger ones which you know will garner all the headlines?!?

I support research into alternative energy from a scientific standpoint. I don’t believe we need to (or find it morally justifiable to) scare the public into supporting our scientific endeavours. It seems to me like Hansen is reprimanding the contrarions for spouting false claims about the issue while he supports false claims that press the issue in his favor. If there is one thing science or myself can’t handle, it’s hypocrites.

If anyone believes I am interpreting that paragraph the wrong way, please feel free to explain. I’m not afraid to admit I’m wrong.