Globe Warmer In Time of Vikings

SEWilco writes "A record of recent global temperatures has been assembled by piecing together the hundreds of studies with past temperature estimates [Discovery, Harvard]. The record shows there was a "Medieval Warm Period" warmer than the 20th Century. This was followed by the "Little Ice Age", which ended around 1900. We're having average climate now. Numerous sources indicated this, but apparently were not gathered into one document" This adds some more background reading to the previously linked Telegraph story.

Comments

In too deep now...

[heldlikesound]

This isssue has be politicized to the point that even with the three or four recent findings that seem to support the case that our quickness to attribute shifts in climate to the actions of man may be completely off base, the side screaming bloody murder for the last 10 years will never admit that they may have been wrong.

Having said that, I am sympathetic to the evironmental movement, there's just nothing I hate more than bad science that persists due to politics.

Re:In too deep now...

[Anonymous Coward]

No offense, but I'd say *you* are engaging in poor science. You yourself use words like "seem" and "may be" (and I do like how you chose to bold the next word, de-emphasizing the speculative nature of the results), but you insist that people who don't immediately admit that they may have been wrong are bad scientists. This is very poor reasoning on your part.

Look at what's been shown: it *might* be the case that Earth's climate has shifted rather rapidly in the past. Without seeing the details of the study and not being myself an expert in the field, I think most of us will accept that. So what? So Earth's climate may have changed rapidly in the past. There have been mass extinctions in the past too (the Cretacious-Tertiary event, for one), but that doesn't mean mankind isn't responsible for the current massive number of extinctions planet-wide.

In fact, it's worse that that. There are many studies showing that the warming probably *is* anthropogenic. The warning trend tracks smack-on with the rise in atmospheric CO2, for one thing. There are studies on glaciers that must have been quite cold for millenia, but are now suddenly warming up. Computer models - starting with the basic physics, mind you - show the same warming trend. We have a mechanism that points to human involvement, we have evidence that it is humans and we have evidence that this hasn't happened in the past.

You bring in three or four new studies which don't even actually contradict the anthropogenic theory and expect people to just suddenly change their views, especially when those new studies don't do anything to explain away the previous results as *non*-anthropogenic? I'd be disappointed with any of my fellow scientists who *did* suddenly switch views based on such poor arguments.

The fact is, politics or not, scientists very rarely suddenly drop old theories and embrace new ones. Evidence seldom comes in so strongly that it makes sense to do so. Usually, it's a slow trickle of data, often over decades, that shift views.

Re: In too deep now...

[Black Parrot]

> This isssue has be politicized to the point that even with the three or four recent findings that seem to support the case that our quickness to attribute shifts in climate to the actions of man may be completely off base, the side screaming bloody murder for the last 10 years will never admit that they may have been wrong.

> Having said that, I am sympathetic to the evironmental movement, there's just nothing I hate more than bad science that persists due to politics.

Thing is, we have good sound physics to explain how various gas mixtures deal with radiated heat, and we have good sound evidence that the amounts of some of the relevant gasses in the atmosphere have grown exponentially as civilization has progressed.

Where's the bad science you're talking about? Do you dispute scientists' claims about the role of atmospheric gasses in the temperatures of other planets?

Just because the earth's temperature fluctuates as a background noise, doesn't mean we should ignore what we're doing to the atmosphere. Yes, distinguishing signal from noise is going to be difficult until the signal is so strong we're fuxored. But there's lots of good science in this beyond the daily weather report.

Re: In too deep now...

[Black Parrot]

> They claim explosive growth post 1980 -- when the BRUNT of the industrail growth was PRE-1980 ... and that just sounds fishy to me --

Ponder the marvels of the exponential curve:

$ gnuplot
gnuplot> plot [t = 20:25] exp(t)
gnuplot> plot [t = 25:30] exp(t)
gnuplot> plot [t = 30:35] exp(t)
gnuplot> plot [t = 35:40] exp(t)
gnuplot> plot [t = 40:45] exp(t)
gnuplot> plot [t = 45:50] exp(t)

You get "explosive growth" on any slice you look at .

After marvelling at that, go check out "Past and future CO2 atmospheric concentrations" and other plots from the IPCC's latest report.

And while the trend toward industrialization may have flattened out in the industrialized nations, look what's going on with the forests in the developing nations right now. See also "CO2 concentration, temperature, and sea level continue to rise long after emissions are reduced".

You really need to look at the gas concentrations in the atmosphere rather than a single slice of human behavior, and the relevant concentrations have been growing exponentially throughout human history.

Re:One Word: Bull

[elmegil]

Feel free to give us some citations for this. I'm sure you're right, but saying so doesn't make it so.

The Vikings and those Damned SUV's!

[R2.0]

Traipsing all over the world in those huge boats, putting out all sorts of greenhouse gasses (methane), when they could have been conserving their energy and travelling only on inshore trips in lightweight, hybrid fuel (sail and oar) dinghys.

All because of their imperialist, war mongering culture.

Bastards.

Hmmm

[Henry V .009]

Too late. In Western societies, more people believe in Global Warming than believe in God. It is to good a story to stay anything but the global boogeyman it is.

Re: Hmmm

[Black Parrot]

> Too late. In Western societies, more people believe in Global Warming than believe in God.

Some of us think that's a good sign, given the relative amounts of evidence for global warming and the existence of God.

Ummm, this has been extriemly well known for years

[Unknown Poltroon]

Just not well known to anyone who hasnt studied the subject. We may hve jacked global warming up by 1 degree celcius in the last 100 years, but were due to rise 3 degrees anyway due to, well, historical patterns. Look up paleloclimatology(sp) and do your own research. Were just coming out of the ice age that killed off roman civilistaton.

Bush and Kyoto

[Ogerman]

If these increasing numbers of studies disproving man-influenced climate change turn out to be true, we can all thank Bush for not plunging our economy further down the toilet by signing the Kyoto treaty.

That being said, I am entirely in favor of *real* environmental protection laws and the promotion of cleaner technologies. By 'real' I mean factors that actually affect people--water and air quality, landfills, etc. And I also think we should switch to a hydrogen economy ASAP, not out of worry about so-called greenhouse gasses, but as the single most effective way to fight terrorism--shut off the money flow to the middle east!

Re:Bush and Kyoto

[derubergeek]

I'll start off by saying I predominately agree so that this doesn't look like an argument. I'm only quoting your one line because I'm feeling lazy...

And I also think we should switch to a hydrogen economy ASAP

The only concern I have with the push toward a hydrogen economy is concern about the source of all of this liberated hydrogen. Those who say H20 are going to have to deal with the idea that nuke's are our current best bet toward that economy, at least if it's going to happen in the near future.

Now, I'm not nuke bashing here. The problem I have is that, the current best source for H without using H20 is oil. It takes significantly less energy to get hydrogen from oil than from water. And the only byproduct is carbon (which I would imagine we'll find plenty of uses for if we have an abundance of it). Which means that it's much more likely that our hydrogen economy is going to be oil based.

I'm also not oil bashing here. The real crux of this is that O2 + HC => CO2 + H20. The cool thing is that plants take CO2 + H2O => O2 + HCs. So we've got at least a cycle here.

But what happens when we take HC => H + C, then toss the C, and recombine H + O2 => H2O? We start depleting oxygen from the atmosphere and don't provide a natural path back (although we do get a lot of extra water out of it).

Just something to think about.

For all the pedants out there: 1) Yes - I know my equations are totally unbalanced and 2) Yes - I know my HC oxidation reaction is ideal - in reality there are also NOx, COx, yadda, yadda, yadda, but the focus of this is on the CO2 issue.

iceland

[austad]

I read an article awhile back, don't remember where, but it said that the vikings inhabited Iceland a long time ago. The climate there at the time was warm enough for them to have large field of grapes and they ran wineries.

Or maybe it was Greenland. Either way, that sort of climate was definitely warmer than it is now. It's kind of interesting to see all of the viking heritage stuff in Iceland. I strongly suggest taking a trip there if you haven't before. Plane tix and hotels are cheap (food and drink is not though), and the people are amazingly friendly. I had an excellent time there.

Re:iceland

[oraevi]

Around the year 900, when the vikings first came to Iceland, the landscape was "filled with trees from the highlands to the see". This is stated in Icelandic scripts, which were probably written in the 13th century. Today there are hardly any trees left. The vanishing of the forests has been attributed to the introduction of the vikings' sheep into the fragile ecosystem but also to a change in the climate.
In Greenland, which is an island almost totally covered by an ancient glacier, we can find hints about how the climate was a thousand years ago by drilling deep into the ice and studying the tiny air bubbles that where trapped there a long time ago. It also shows that the climate was warmer a thousand years ago.
However, Iceland never had "large fields of grapes". These were the words the viking Leif the Luky used to describe the land he found sailing south-west of Greenland. In the year 1000 he discovered America and called it Wineland the Good.

Research sponsored by who?

[Glass of Water]

The trolling was quite predictable on this one. If you RTFA, you'll note that:

The study - funded by NASA, the Air Force Office of Scientific Research, the National Oceanic and Atmospheric Administration, and the American Petroleum Institute - will be published in the Energy and Environment journal.
(from the Harvard article)

I think the conclusion hastily drawn by many of my fellow slashdotters is an example of post hoc ergo propter hoc. In other words, the argument that is being made goes like this: Global warming is caused by a factor other than pollution. Therefore, pollution does not cause global warming.

That said, I agree that bandwagon environmentalism is a bad trend. It does not seem, however, that the current US administration is in danger of subverting our economy with overzealous environmental regulation.

Re:Research sponsored by who?

[jellisky]

In other words, the argument that is being made goes like this: Global warming is caused by a factor other than pollution. Therefore, pollution does not cause global warming.
--------------

Hate to break it to you, but that argument is perfectly valid since it's just a restatement of the first statement. It's a perfectly valid and logical argument.

If the argument went:
Global warming in this study is caused by a factor other than pollution; therefore, pollution does no cause global warming.
then there'd be a logical fallacy.

I'm also not seeing where your post hoc ergo propter hoc fallacy is occuring. Perhaps you are insinuating that the scientists in the study are claiming that, since pollution is a modern effect and there was global warming before modern times, pollution was not a factor in the climate change, and thus, is not a factor in global warming at all. From what I read of the articles, I don't see any place where they say that pollution is NOT a factor in current climate. The insinuation of the articles seems to be that perhaps we are overestimating pollution's effect on the climate system, which is not a bad insinuation given recent studies on the carbon dioxide budget (see almost anything published by Dr. Scott Denning over the last two years). As for the /.ers making logical fallacies, let's just say that I wouldn't be surprised... but your example leaves much to be desired.

As an atmospheric scientist, I've seen enough global warming results from people on both sides of the fence that I feel comfortable saying something that may surprise many people: we don't have enough of a clue of what's going on to make any sort of accurate prediction of climate. These big old climate models that run for months on our supercomputers aren't very useful since they rely on so many parametrizations. And how these parametrizations are implemented can seriously affect the results of the models. We're finding out that the climate is so chaotic over even long times with averaging that prediction is difficult, at best. But, we're making strides in understanding the feedback mechanisms that are present... slowly but surely. In other words, expect even the most basic ideas of the climate scientists to be in constant flux for another decade or two. Climate science is much like nuclear science was during the beginning of the 1900's.

-Jellisky

Re: What I don't get. . .

[Bastian]

Is why so many people seem to want to oversimplify the situation.

As with any set of data, it's not all signal and it's not all noise. Much of the research in global warming may be due to political motive. (Though personally, I'm not inclined to agree that environmentalism is a purely political issue. I have a lot of reasons to be concerned by the idea that Florida might start shrinking in the next century, and none of them have to do with politics.) However, the focus of all the stuff I've heard about lately is on trying to figure out just how much of the change in global climate over the past century is due to natural fluctuation and how much is due to pollution.

Besides, even if it turns out to be entirely due to nautural fluctuation, it seems that it would be in our best interests to still modify the actions of humanity as a whole to promote a global climate that is best suited to humans. People don't think irrigation is a stupid idea because Mother Nature didn't put a body of water in the middle of every cornfield. The issue at hand should be what action is ultimately the most beneficial to the world.

Typical Slashdot Reasoning

[Bastian]

It's been proven that the dog farting can clear a room. Therefore, Joe's farts can't clear a room.

There's no reason to believe that there can't be two or more contributing factors.

Warmer in the time of Vikings

[Jo.Calder]

Required reading for anyone entering this thread: Still waiting for Greenhouse which has a pretty comprehensive treatment of the whole greenhouse show.

Liberate Vinland from Yoke of Canadian Oppression

[SgtChaireBourne]

Liberate Vinland from the Yoke of Canadian oppression!

Seriously, Black currant (Ribes nigrum), vinbär/solbær, makes excellent wine grows in cooler climates. Wine from grapes is probably an artifact of mediterranean culture / continental Europe. However, mead was more common as the wax was a sought after trade good for the Byzantine empire.

Cooling of the climate in the 1200's seemed to have killed off the Greenland colonies. The Viking groups (Goths, Svear, Danes, Norrmen) had tradroutes from China/Bagdad to the east coast of what is now Canada. Iceland, Greenland, Shetlands, Froes, and parts of Ireland, England and Scotland were all settlements.

Aside from warm weather, technology made the long trips possible. Iron nails and sails were just two of the improvements. Prior to that they were closer to home. The basic ship, even before sails and iron nails, was strong and light because they had no saws. Hewn planks have about twice the strength and flexibility of sawn ones.

Not all changes in technology are improvements. Later, European-style ships were heavier and less maneuverable and could neither handle shallow rivers nor be portaged.

Pulling numbers out of my ass while drunk

[Unknown Poltroon]

Im just remembering back to a graph showing average earth temps for the past several million years. When you look at the graph, there are ice ages constantly, with little plataus of warmpth ever so often, in a regular pattern. We appear to be right at the start of one of these plateaus, and there are temperatre spinkes up and down on these. Very interesting.

THis time period also relates bact to the Anasazi indians and such in the southwest USA. In the warm period, they floursed with corn farming, and as the climate cooled, the resources became scarce, and they started fighting with each other. Current issue of discover has an article.

Re: What I don't get. . .

[elmegil]

Though personally, I'm not inclined to agree that environmentalism is a purely political issue.

I used to think that too. Then a conservative friend of mine noted that he had quit the Sierra Club after repeatedly having to sit through tirades about Republicans that had not one damn thing to do with actual environmental issues. Looking around, talking with him, reading some of what passed as "discussion" in environmental circles, it became quite apparent that the majority of "greens" have hooked their wagons to a particular rigid point of view about what is and what should be, and have stopped thinking about the general point of science, which is to be flexible and seek truth.

Of course this goes on in most scientific fields--an orthodoxy is established, moves some sort of progress forward, and eventually something comes along to break down or modify the orthodoxy in strange new directions--but in environmental science, and particular around the issue of Global Warming, the orthodoxy is particularly entrenched and fighting particularly hard to hold its position regardless of the facts.

I don't think any reasonable person is going to argue with you that the right thing to do is to modify human behavior to best balance between "progress" and the environment (my conservative friend is among those reasonable people). Unfortunately, most of the so called "environmentalists" have already made up their mind and don't want to discuss it any further. It's like trying to have a religious discussion with Jerry Falwell, and people are just as incensed when these people try to shove their environmental religion down our throats as they are when the (im)Moral Majority does.

Re:you are completely missing the point

[elmegil]

No, the real question is why you are assuming, a priori, that our greenhouse gasses are the sole cause of the current warming trend. Especially in light of evidence that in the past we had warming trends that were much more significant in the absence of the same greenhouse gas production you're trying to stop.

Show me the money. Show me the proof (not a computer model which can be jiggered any old way to fit your biases--and I don't mean that people are doing so consciously or with malice, but it does happen) that our own contributions to the climate are more significant than those of the sun or of other factors.

I think given that we don't even half understand all the things that influence climate (we can't predict weather reliably more than a day or two in advance even now) it is far too premature to say we know for a fact that this tempurature spike is our fault. Reality is, it would be good to limit things, but we have to negotiate from the standpoint of where we really are: we SUSPECT rather than we KNOW. People who run around saying we know are only damaging the credibility of anyone else who has honest concerns about our contributions to global warming.

Re:One Word: Bull

[jackjumper]

Don't be so quick. The vikings abandoned their greenland settlements when the temperature dropped.