You seem not to comprehend at all how collaborative reports of this kind are put together. It is done in a series of levels.
Here is a listing of the authors of the assessment previous to this one; I am sure the current report was generated in a similar fashion. There are different levels of contributers for each section of the report: The Coordinating Lead Authors , who are responsible for the synthesis of information; Lead Authors, who assemble the information provided by the Contributing Authors; and the Contributing Authors, who have conducted the basic research and provide the data to the Lead Authors. In addition, there are Review Editors who review each chapter.
In scientific journals in medicine and physics, it is quite routine for peer-reviewed articles to have dozens, sometimes hundreds of authors. Even in biology, synthetic articles can have more than 20 authors. So if you consider each chapter of the report as equivalent to a paper, this is not at all unusual.
The simple solution, by the way, is a sunshade. A fleet of satellites between here and the sun, with giant solar sails, slightly too heavy to move. We could cut the solar energy reaching our planet by at least one percent that way.
In answer to the OP, as Squink noted, the fact is that the amount of heat we produce pales in comparison to the amount that we receive in the sun. So, this is one case where those who say, “How can we have a significant effect compared to much stronger natural processes?” are in fact correct.
Unfortunately, however, it turns out that we can have a dramatic effect on atmospheric chemistry…in particular, the concentration of greenhouse gases in the atmosphere, and can thus affect how much of the prodigious amount of energy we received from the sun stays here rather than being radiated back into space. The reason we can is precisely because of the fact that these greenhouse gases are such small fraction of our atmosphere…i.e., the majority components, diatomic molecules of nitrogen and oxygen, are unable to absorb any infrared radiation. Because CO2 is such a small fraction (and because it has a long lifetime in the atmosphere), we can significantly alter that fraction. Another contributing factor involves the most common greenhouse gas in the atmosphere: water vapor. While there is too much water vapor and its lifetime in the atmosphere is too short for us to have a direct effect on its concentration, it does turn out that the equilibrium vapor pressure is a strong function of temperature…So, there is a positive feedback whereby if the temperature of the earth is increased by other means (such as increasing CO2), this results in an increase in water vapor which then, because it absorbs infrared radiation too, results in a magnification of the warming.
By the way, there was a recent paper that appeared in some back-water journal by a couple of scientists (one who is apparently a petroleum engineer at Stanford and the other who nobody can really figure out who he is). This paper, which has garnered much more attention than it deserves because it is one of the few papers that claims that anthropogenic global warming (AGW) is bullshit that has recently been able to make it into any science journal, actually does the calculation for how much energy humans release directly through burning fossil fuels and the resulting temperature rise and then tries to use this as disproving AGW, completely ignoring the “greenhouse effect” altogether!
The way that they have decided this is being engaging in a process that we call “science”. I.e., they have actually discovered the physical laws that govern the transfer of energy (mostly back in the 18th and 19th centuries…although some aspects extend into the 20th) and they can actually do calculations and understand things rather than just talking nonsense.
Again, there is this thing called “science” that allows us to understand the natural world around us. Of course, if you want to believe that there is a massive conspiracy perpetuated by the scientists and lots of other folks and the only ones who seem to recognize this anymore are a dwindling number of fossil fuel companies and some conservative / libertarian think-tanks and folks associated with them, there is little I think I can do to disabuse you of the notion.
The thing that makes my head spin is the group of people that says that there’s no global warming or that it’s all a trumped-up hoax. I fail to see how someone can say there is NO global warming. we’re more than happy to debate the amount of global warming or how MUCH man contributes to it, but to say it’s not happening is pretty absurd to me.
I could probably dig up something. It’s what I call a technically simple problem. All it requires is money and labor. All we’d need would be a load and a half of rockets and a bunch of satellites that were too heavy to move with photon pressure. We’d probably have to replace half of them every ten years or so. Basically, the only issues here are engineering ones, and engineering problems can be solved.
I kind of like the L1 proposal. Seems simplest.
Anyhow, it can be done. It won’t be especially cheap, but it will work, one hundred percent for certain. Cut down the solar energy, and presto, less global warming.
Science can save the world, man. We aren’t doomed yet.
The interesting thing about this is that line: “The US government wants the world’s scientists to develop technology to block sunlight as a last-ditch way to halt global warming, the Guardian has learned.” On that point, I agree with the Bush Administration: research on such “last-ditch” efforts is certainly needed. However, the problem is that by “last-ditch” the Administration seems to mean what you turn to after having tried everything that Exxon and Western Fuels Association (a coal conglomerate) is willing to wholeheartedly endorse. Some of us believe some of the efforts we might want to try first are ones that, heaven forbid, Exxon isn’t entirely pleased with!
Of course, any sort of geo-engineering scheme based on reducing the amount of sunlight that we receive won’t do anything to relieve the issue of the acidification of the ocean from the rising CO2 levels…a problem that is less well-understood, and has received less attention, at this point. [I noticed that it did actually get mentioned in this new IPCC report.]
No, it is not a 90% certainty. It is a 90% consensus, which is a different animal entirely.
Remember that prior to Gregor Mendel, there was a greater than 90% consensus among scientists, breeders, and horticulturists that heredity was mostly a blending process between the traits of the parents.
A good theory leads to a new consensus. Right now, I’m not entirely convinced that we have a great one.
Where are you getting that its 90% consensus from?
From the ipcc summary of the report, which I assume is where the 9 out of 10 numbers are coming from:
The report then goes on to assign “very high confidence” to the fact that humans are causing the average global temperature to increase.
So its a measure of confidence, not a measure of how many scientists agree with the finding. The way you phrase it makes it sound like 10% of the scientists disagree with the report, which isn’t the case. Also note that at least 9 out of 10 is the heighest possible score, there isn’t a 10 out of 10 category.
No, you have read it wrong. The “Summary for Policy Makers” report is a 100% consensus on the part of the lead authors; every word was reviewed and agreed on. The conclusion of this report is that there is a better than 90% probability that global warming is occuring, and it is mostly due to human impacts; in other words, this conclusion is “very certain.”
I’m sure this must be based on your objective review of the science yourself. Your politics of course have nothing at all to do with it.
When the opinions of 600 of climatologists differ with your own on a subject involving climatology, it might be time to review your opinion with a skeptical eye.