Little Ice Age: It Was Not the Sun 375
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.'"
University of Boulder? (Score:3, Interesting)
Not the University of Colorado at Boulder?
Re:We didn't really know how things worked before (Score:0, Interesting)
GW !=AGW
This is like somebody asking you to prove that God doesn't exist. You can prove easily that God doesn't exist, but it's impossible to prove that god doesn't exist. They use this little semantic crevice to get their stupid traditions treated with respect.
I posted a little bit ago about the lack of a scientific consensus concerned AGW, and got modded troll. The response was that of course there is one, don't ask why, don't question authority, you're an idiot, -1 troll, etc. Ask someone about GW, and you'll get patient, comprehensive evidence. Why the difference in rhetoric?
Why has there been no tremendous effort to respond to the usual AGW criticisms? Why did the temperatures start going up before carbon levels did? Why are increased carbon levels sometimes said to be more strongly correlated with lower temperatures? How do we measure the amount of carbon we introduce compared to the rest of nature?
I like a response to these questions without people assuming I'm a troll. Trolling is semantically congruent with curiosity anyways.
Re:We didn't really know how things worked before (Score:5, Interesting)
There are at least 5 reasons I can think of for that phenomenon:
1. Some are shills for by the majorly carbon-emitting industries. There's no reasoning with this group, because they aren't here to reason or discuss, they're here to do their job of sowing doubt about whether global warming is real. Similarly, there may be commenters who aren't paid PR people, but work for these companies (e.g. a friend of mine who does geology on oil rigs for a living), for whom the "It is difficult to get a man to understand something when his salary depends on not understanding it" truly applies.
2. Some believe that placing a high value on science involves being skeptical of anything not definitively proven. With anthropogenic global warming, because there's only 1 planet Earth (that I'm aware of) there's no way to definitely prove things one way or the other. This is true even if the vast majority of the research supports the theory that AGW is causing significant changes to the climate of the Earth.
3. Some are politically libertarian and tend to strongly oppose government action not concerned with enforcing contracts, protecting property rights, or preventing violent attack and/or sexual assault on a citizen. If AGW is true, and private enterprise can't or won't act to stop it, then stopping it requires significant government intervention in the markets, which dismantles the idea that libertarianism can solve all human problems. It's not dramatically different from a reaction you might get to a devout born-again Christian discovering definitive proof that Jesus never existed.
4. Some are unwilling to make the dramatic changes to everyday life that would be needed to reduce CO2 emissions in the short term. It would mean changes like having to move your home so you can commute to work without driving 30 miles, or having to put your washing machine on timers so the load runs at 3 AM rather than right now, or keeping your home at 55 F in the winter rather than the 70 F you find comfortable. Nobody wants to do that if they can think of a short-term alternative. This also manifests itself in an absolute faith that scientists and engineers will somehow come up with a solution that will solve the problem completely without requiring any kind of conservation effort.
5. Environmentalists have been guilty of overstating their case in the past, so some are reluctant to believe anything they say.
OOOhhhh yeh! (Score:4, Interesting)
Same with anti vaccination loonies, and creationists, they all use the same tactics of internet circle jerk where one denialist site quotes another as a reference. The facts whilst interesting are considered irrelevant.
I have got to the point where i dont even bother to challenge them anymore, as their objections are based in their self interest allowing them to ignore relevant facts and use nit picking irrelevancies to support their case.
For some reason what seem to be otherwise intelligent people here on Slashdot show a remarkable degree of stupidity on this issue. Then again a lot of them propound libertarian claptrap too, so I guess I shouldnt be too shoucked.
Science is settled (Score:1, Interesting)
Re:We didn't really know how things worked before (Score:1, Interesting)
6. Some have listened to both sides of the argument and have realized that the skeptics have driven a bus through the theory of man made global warming and just don't believe the scientists who tend to support that theory anymore.
Re:Global meltdown, they say ... (Score:2, Interesting)
Sadly this post is a bit of a joke. This sort of paper comes out at least once a month. People just really, really want to believe this it seems. They are slowly getting more convincing, but as you can see in the paper, the timing doesn't exactly match very well. Some of the changes occur rather a long time after the earliest eruption, which throws their whole thesis in serious doubt. If the plant disasters they claim indeed occurred at the dates claimed, why isn't that massive sudden cooling in the history books along with a few revolutions occurring at those dates ? Why did the cooling last so much longer than similar volcanic eruptions ? At the very least they're missing something, at worst, they're just wrong.
They're also invoking feedback effects. That's cute, but feedback effects obviously never cause anything, it's a cop-out. This sort of claim gets weaker and weaker once you realize that they claim a tiny, tiny effect (slight albedo reduction, a sort of (tiny) "nuclear winter" caused by volcanoes) and everything else followed by necessity (it cooled further because it was cooling. Great ! If so, why did it stop ? No answer).
What this paper claims is that the little ice age occurs in simulations of their events, after tweaking the values a few times. Which values ? They need to rather greatly prolong the expected cooling a volcanic eruption causes. Great. But the Mauder minimum just happens to coincide really really well with the little ice age. And the timing matches a lot better than their volcanoes. Is that just a coincidence ? Nobody really thinks so, and this will be one of the many papers that fails to convince people of that fact.
If this paper is true, that little ice age should probably be classified as a "false start" of a real one. It tried to start and sure enough, temperatures started dropping (enough to cause the extinction of several countries), but for some reason that this paper doesn't go into, it didn't happen (and the modern world wouldn't have happened if it did, we'd be back in the stone age if not extinct instead of on the moon). The feedback loop cooling the planet got triggered, ran for a while, and then just ... died. Why ? It doesn't seem to have had any false starts the previous times. In fact this feedback system has proven extremely unstoppable in the past, including a few times with a massive co2 increase, which failed to halt temperature drops (at least in the long term it failed, in the short term we're guessing). They could at least have said something akin to that the sun may not have started the little ice age, but it looks like it ended it (at least the Sun may have sufficient power to do so).
That's another bit of an elephant in the room. It is "about time" (give or take 5000 years) for another huge ice age to start. Was the little ice age a "false start" ? If it is, that seems a rather unique event. We don't yet know what causes ice ages (and no, it's not an iceberg blocking the gulf stream as half of the internet seems to believe, that would suck for Europe, as last years' UK snow disasters would become yearly events, and rock for Canada (unless Canadians like skiing), but it doesn't really change temperatures). We just know that ice ages happen with alarming regularity in the past, and that their alarm clock is about to go off.
Regardless, this paper is one of many with this claim, and it's not exactly better than most. They have some new, real-world data which is rather unique, but otherwise ...
There's another problem I'd like to point out about these simulations. They show us the real nature of causality. No one cause "causes" something else. In this paper the "cause" of global cooling during the middle ages is "a number" of volcanic eruptions, which activated a number of physical effects due to their location and their distribution, which were followed after a century and a half by another 3 volcanic eruptions, and the warming between the two caused a change in ocean salinity in one or t
yes they can with Solomonoff's inductive inference (Score:4, Interesting)
The belief that "if you don't have replicates of some subject to use as a control group, you can't know if a theory will make good predictions about this subject" is false.
We only have one universe , with no control group, but scientists have been able to accurately predict things about our universe.
Solomonoff's inductive inference is a mathematical formalization of how to make a good prediction in a unique universe. It is a mathematical Occam's razor: shorter theories give better predictions, provided that they perfectly describe previous observations.
https://en.wikipedia.org/w/index.php?title=Inductive_inference&oldid=471899642 [wikipedia.org]