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Little Ice Age: It Was Not the Sun
vikingpower writes "The Little Ice Age, lasting from the end of the Middle Age into the 17th century, may very likely have been caused by the combined effects of four major volcanic eruptions and increased sunlight reflection by increasing sea ice, the so-called Albedo effect. ... The University of Boulder has a press release with maps and photographs. Bette Otto-Bliesner, one of the scientists behind the 'volcano + sea ice' thesis, fields an earnest warning against drawing conclusions too quickly from this research: 'I think people might look at the Little Ice Age and think that all we need to save us from rising temperatures are some volcanic eruptions or the geo-engineering equivalent [...] But when you see what happened when global temperatures dropped by just one degree and you look at current predictions of six or seven degree increases for the future, you realize how precarious things are for life as we know it.'"
> Shouldn't all science be questioned?
Yes - intelligently questioned by people who are qualified to criticize it. And who "question" it by doing their own research, investigation, hypothesizing and testing... which is not the same as digging up spurious out-of-context quotes and raising biased, uninformed objections for political reasons.
There's a difference between questioning a theory based on evidence to the contrary and questioning it simply because it is controversial. One of the few other scientific theories that seems to enjoy this distinction is the theory of evolution. However, you'd be hard pressed to find as many slashdotters making the same argument against that theory.
Still #1 -- Lonely Gay Geek
One of the few other scientific theories that seems to enjoy this distinction is the theory of evolution. However, you'd be hard pressed to find as many slashdotters making the same argument against that theory.
Actually, you will. Check any Slashdot story dealing with evolution, and you'll see a ton of comments pushing creationism (usually in its "intelligent design" guise) very often using the same "we should always question theories" argument. Sadly, almost none of these people seem willing to question the theory of gravity in the most obvious manner.
The correlation between ignorance of statistics and using "correlation is not causation" as an argument is close to 1.
Yeah, computer models suck. That's why airplanes keep falling out of the sky, why missiles never hit their targets, and why you can never get the temperature of the brew head on your espresso machine just right. Er, wait, you can do all of these things. Because of computer models.
Remember when the weather forecast was always wrong? It's been really remarkably precise recently when I've followed it, which I do a lot, because I enjoy outdoor sports. It's been scarily precise. Predictions a week out come true with astonishing regularity. This is weather, which is rapidly changing and chaotic, not climate, which is slow and relatively predictable.
The problem with your completely ignorant assertion here is that in fact the models do appear to be getting more accurate, not less. The debates are not over whether there is warming, but over how much, and what the effect will be, and how soon the effect will come. Nobody is debating whether it's coming except people who are making a short-term killing on carbon externalities.
Therefore the fact that people do not like the implications of AGW does not, in anyway, make it less true. We are not choosing clothes from a rack. We are not debating whether the purple shoes will go with my slacks. And it's the implications that denialists do not like. Notably, no-one ever questioned Tyndalls experiment, nor whether the greenhouse effect was real until it became clear from the numbers that we needed to change our habits. Then suddenly, the whole theory was controversial.
So how many times do you answer the same question before you realise you're dealing with a troll or a shill? How many people still link and quote Anthont Watts thoughroghly descredited claims? Should the time cube guy be allowed to chew up research dollars just because he has a bunch of ideas contrary to modern physics?
I think you are also bluring the "argument from authority" thing (which is about relying on a single source), science does in fact carry a certain authority in it's calim to have the best answer, if not the correct answer. It's authority comes from a meritocricy that Popper called "the republic of science" and what everyone else calls "consensus". It's the difference between "science says" and "a scientist says".
And did you exchange a walk on part in the war for a lead role in a cage? - Pink Floyd.
The original article is about the Little Ice Age primarily, and the only tie-in is the comment warning against relying on volcanoes to save us from warming / geoengineering man-made "volcanoes" to fix warming.
But, ok, you want to ask the question "is it actually warming?" I'm a climate scientist-ish, I'll throw in a line. I recommend skepticalscience.com for it's superb evidentiary support for the theory of anthropogenic global warming (a.k.a. climate change).
Yes - we have ample data demonstrating that it is warming, not only in the air but in the surface waters of the ocean (water absorbs some of the heat, it turns out - if only it would absorb more of it!). We have really really obvious evidence (seriously, just look at the satellite pictures) of dramatic summer sea ice loss. The troposphere (where we live - where our weather happens) has warmed about 1.3 degrees F over the last 100 years. This might not sound like a lot, but just integrate 1.3 degrees over the whole planet, and you're talking about a significant amount of energy.
The stratosphere has cooled up to 6 degrees Celsius (yeah, that's right, mixing up the units) in some places, and higher atmospheric layers have cooled even more. Now, you might ask, why the cooling - this is supposed to be global WARMING, right? The mechanism behind stratospheric cooling is a bit complex, but think about it this way: Greenhouse gases (GHG's) trap more heat (absorbed and re-radiated long-wave energy) in the Troposphere (the lowest layer, where weather happens) than we would otherwise have. If that extra heat weren't trapped in the lower atmosphere, it would have to go somewhere else, right? So where would it go? It turns out, it would go back into space or, more importantly, into the upper layers of the atmosphere (stratosphere, mesosphere, ionosphere). Essentially, the GHG's play favorites with the atmosphere - they give the lowest layer more heat while depriving the higher layers of their ordinary allowance.
Incidentally, this phenomenon allows us to distinguish GHG-driven heating from sun-driven heating. If global warming were caused by the sun alone, the temperature would increase in all layers of the atmosphere - the sun doesn't play favorites.
But wait, how do we know it's people? Physics tells us CO2 absorbs long-wave radiation (and then re-radiates that energy in all directions). Simple energy balance calculations tell us that without CO2 and other greenhouse gases (but mostly the CO2, as it is slower to enter/leave the atmosphere than H2O) the earth would be too cold to support most life forms. Over and over again in Earth's long history, higher concentrations of CO2 are associated with higher temperatures (the very early Earth was very warm, despite a weaker sun - this is known as the Faint Young Sun paradox - but greenhouse gases were more abundant). We're pumping this gas into the atmosphere with careless abandon, and we can measure and observe that much of it stays there (removing CO2 from the atmosphere permanently by natural processes takes a loooong time). Even if we didn't measure warming and we couldn't measure CO2 (did I mention we can measure warming and CO2? We do it all the time) the laws of physics and the principles of chemistry allow no other possible conclusion than a future of warming (for most of us) and cooling (for anyone unfortunate enough to be stuck in the upper atmosphere).
Sorry for the long post. Also, don't think for a minute someone does serious climate science without asking the questions "are we sure we know what we know?" or "are the computer models any good, like, at all?" about 3 times before breakfast. Seriously, people, we're pretty smart apes, this isn't "too complicated" or "too difficult" for us humans to figure out.
Using a "convenient one word label" turns the debate from scientific to political.
But this is a political debate, not a scientific one. The scientific debate is conducted in journals and conferences not on this kind of forum and not by you and I. The scientific debate is largely over, or rather it has moved on from the issues which are still hotly contested in the political debate.
It's focusing more on "us vs. them" than discussing the real issues at hand.
The "real issue at hand" is what policy position, if any, ought to be adopted in light of the now established science, or if you prefer, the current best available science. Denialists have no interest in discussing the real issues. Quite the opposite, they are concerned with stopping the real issues from being discussed at all.
We call people who disrupt democratic process with bombs with a convenient one-word label: 'terrorist.' You may object, but it makes conversation more convenient. So what would you call people who disrupt the democratic process with disinformation about science, regardless of whether it's about climate, AIDS, vaccines or whatever? We usually find it easier to identify these people as 'deniers' or 'denialists.' They would like to be called skeptics, but that is actually only more disinformation.