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

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.

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.

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.

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.

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.

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: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.