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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.'"
After 5 billion years, the sun is basically in steady state. I would not expect to see fluctuations over the type of timescales that human beings exist on....
the sun is pretty steady, a middle-aged star, but there are still some small variations in solar intensity. The hypothesis was that the Little Ice Age was correlated with the solar "Maunder Minimum," a 75-year period during which the sun had no sunspots (and hence presumably was about 0.07% lower in brightness).
What this work did was put a good date to the start of the Little Ice Age; using radiocarbon dating to determine when the plants killed by the advancing glaciers died... and the dating shows the Little Ice Age began well before the Maunder minimum. The Maunder minimum didn't cause it, very definitely.
http://www.geoffreylandis.com
They do talk about it. You just (evidently) don't listen.
Global temperature increase shifts the atmospheric circulation cells, so that they land in different places. It shifts the jet stream, so that weather is carried to different places. It shifts oceanic currents; there's a big concern that global warming may actually result in a major drop in temperatures in northern Europe. There are many factors that decide what the temperature will be outside your house today; global warming is not the largest factor by a long shot. But where the Hadley Cells, Ferrell Cells and Polar Cells land has a big effect on the weather you experience, and that _is_ affected by global temperature increases in the one degree range. These effects aren't necessarily temperature increases; they are just as likely to be more energetic storms, or droughts, or floods.
However, it's also worth noting that 1 degree is currently considered a fairly unrealistic best-case scenario, because since we started trying to take some weak action to address Global Warming, China seriously ramped up the amount of coal they're burning, so atmospheric CO2 levels are going up faster than predicted.
On balance it's probably natural for geeks (many of whom are naturally inquisitive) to question ideas which insist on substantial changes to our lifestyles with tenuous evidence behind them
To quote Wikipedia:
No scientific body of national or international standing has maintained a dissenting opinion; the last was the American Association of Petroleum Geologists, which in 2007 updated its 1999 statement rejecting the likelihood of human influence on recent climate with its current non-committal position.
And so all these organisations came to the conclusion that human activity is playing a key role in global warming without any "credible evidence" (to use your phrase)?
Can you name a me a single AGW "denialist" that you deem to be qualified enough to have their theories and research taken seriously?
Yes. Richard Lindzen. If you ask for 2 it gets difficult ... there are a few "luke-warmers" though.
Now can you name me a single scientist who denies the existence of gravity, that you deem to be qualified enough to have their theories and research taken seriously?
Exactly!
See, that's the problem. Any scientist that questions it is immediately deemed unqualified or even unethical simply because they have bothered to question it.
Oh come on Archer. The criterion for "suitably qualified" is not whether they personally agree or disagree with any position. It is simply whether they are literally suitably qualified, which is to say, are they working and publishing (in an ISI listed peer reviewed journal, i.e. not a phish journal like E&E) in the field, the holder of a chair in the relevant discipline etc.. And ultimately it's not what scientists say, but what the bulk of the published science says that we must defer to.
Nor is there universal agreement among most expert climatologists. But the baby questions, such as is anthropogenic carbon in the atmosphere rising; are mean global temperatures rising; and are the two causally linked, are now settled in the affirmative. The scientific debate has largely moved on. And recent attempts to revive these questions by the very few suitably qualified scientists who do disagree with the mainstream has invariably resulted in disaster: Witness Lindzen & Choi (2009) (In Lindzen's favour, once the flaws in this paper were pointed out he withdrew it without hesitation), or the debacle surrounding Spencer and Braswell (2011).
Now once he was presented with the body of the science, the editor of Remote Sensing (where Spencer and Braswell appeared) realised he'd been duped and took the appropriate course of action (for which see the link above). When are you going to wake up Archer, and face up to the fact that you've been duped too?
All theories, from gravity to evolution generalizations that can never be exhaustively tested, but that are to some degree accepted because they make testable predictions that have turned out to be correct. For example, we theorize that all masses, past, present, and future exert a gravitational force on all other masses, but almost all of the masses in the universe are not directly accessible for testing--we have tested only an insignificant fraction of them.
Here's a list of some of the predictions of climate science that have been tested and have turned out to be correct
> As far as I know no one has created a model of the earth to test global warming or bred a large number of animals to create a new species.
No-one that is, apart from those that have. There have been a fairly large number of the latter, both observing and inducing speciation in plants and animals.
There are plenty of earth models for climatic and other purposes. It's clearly not practical to make physical models, so we have to make do with software ones which don't have such practical constraints. Their accuracy can be tested by seeing if older data can be used to predict more recent data (hindcasting), for example can data gathered from 1900 to 1960 in a given model be used to predict what the conditions were like in the 1960s? If they do, then you might consider some of that model's future predictions trustworthy too. This technique is used to test models of individual parts of an overall climate model, such as temperature changes, cloud actions, El Niño events, gas mixtures etc. Generally these models will only ever get better as research improves and computing power increases. Still, they are an approximation (as all models necessarily are), but as the IPCC said: "Despite such uncertainties, however, models are unanimous in their prediction of substantial climate warming under greenhouse gas increases". More info.
0) The people shouting loudest about how important this is stand to gain a significant amount of money, power, and public notice if people believe and act on their claims.
Everywhere I go, I see teachers driving Ferraris, research scientists drinking champaign...
As a research scientist, the best that they can expect to get, and in fact the goal that so many of them have in mind after 10-20 years of hard research is... a job which isn't guaranteed to terminate in 3 years.
And, the best way do do that is to make a big name for yourself by turning over the old scientific establishment and coming up with something striking and new (supporting AGW definitely does not qualify as anti-establishment).
If you think there's a cabal of scientists banding together on global warming for the money and power, then you are either astonishingly ignorant or a total moonbat.
SJW n. One who posts facts.