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Nature: Global Temperatures Are a Falling Trend
New submitter sosume writes "An article in Nature shows that temperatures in Roman times were actually higher than current temperatures. A team lead by Dr. Esper of the University of Mainz has researched tree rings and concluded that over the past 2,000 years, the forcing is up to four times as large as the 1.6W/m^2 net anthropogenic forcing since 1750 using evidence based on maximum latewood density data from northern Scandinavia, indicating that this cooling trend was stronger (0.31C per 1,000 years, ±0.03C) than previously reported, and demonstrated that this signature is missing in published tree-ring proxy records."
this should be good!
"Global Temperatures Were a Falling Trend."
The long term graphs in TFA show a long term decline, but they all still kick up sharply at the end when we get to the industrial age.
Drill baby drill - on Mars
Grats, slashdot for the misleading title. It is not like it was unknown that there has been a cooling trend on a 1000-year timescale. It may have been stronger than previously thought. This paper estimates it at -0.32 K/ka - Mann 2008 had it at -2.something K/ka. It was to be expected that the denialist would latch onto some cherry picked sentences - business as usual.
Ubi solitudinem faciunt, pacem appellant.
That wasn't the point of the paper. You interpret it as flamebait because you believe that it presents an argument against AGW. It does no such thing, but you have revealed your own bias.
So, you want to throw out data that doesn't fit your model?
Perhaps you should link up with the Creationist institute?
Do not pick and choose words or results from scientific papers. The scientists who published this paper are part of the X who agree that CO2 emissions are warming the planet.
Palm trees and 8
Another in a long list of inflammatory and inaccurate articles from secondary sources.
Like yesterday's baloney about Obama's executive order.
The first thing you should learn as a thinking adult is to read the primary source. In this case the Nature article.
The fact that climate change took place centuries or even millennia ago doesn't prove that it was not caused by people. Humans have been doing things to affect the climate for a long time.
Charles C. Mann, in his excellent book 1493, discusses a theory that the "Little Ice Age" (a period of cooler than usual temperatures from roughly 1550-1800) was the result of the Columbian Exchange. Basically, the Native Americans had populated large portions of the New World, and in so doing had cleared most of the forest lands. After Columbus and his successors arrived, the Native Americans died at an insane rate from European diseases, and new forests grew across vast swathes of the Americas. This in turn resulted in far lower CO2 levels and consequently lower temperatures.
What stuff? The stuff you happen to believe in?
As you can see in the graph of TFA, it has been colder and warmer than the mean line (hint: its the red dots)
As you can see in the graph of TFA, it has been colder and warmer than the mean line without us doing a lot (hint: its the red dots)
The problem is that you WANT a warmer climate and when you are proven wrong then the "cautionary principle" is called in to underline your presumptions. Data, or it wont happen.
TFA --> (hint: its the red dots)
No 2000 years is nothing, let alone 50 years of industry by men. Yes, it has been slightly longer, but it was only until the postwar economic boom since we really cranked up the CO2 and other natural gases.
quo errat demonstrator
rm -rf --no-preserve-root /
It is always about the dose. A small amount of oxygen in the air is necessary for us, but too much oxygen will kill you.
A small amount of CO2 has prevented a Snowball Earth for the last couple 100 million years, but the recent rise has already reduced crop yields.
thegodmovie.com - watch it
Whatever you choose to call them, it is clear that there are a group of people who like to style themselves "skeptics" who reject the overwhelming consensus of climate scientists--a consensus that has been reviewed and endorsed by the National Academy of Sciences (along with nearly every elite professional scientific society in the world). It is also clear that this "skeptic" point of view has been supported by an extremely well-funded public relations campaign backed by individuals and organizations who have a financial interest in sales of fossil fuels.
A distinguishing feature of this kind of "skeptic" is that their "skepticism" is notably one-sided.
For example, a genuine scientific skeptic will read the scientific literature on historical climate reconstruction and will reach the following conclusions: Reconstructing global temperatures prior to actual temperature recording is difficult, and relies on the use of "proxies," which are indirect methods of estimating temperature. These are subject to a variety of errors and artifacts, and global coverage is spotty. In addition, there is limited information regarding factors driving temperature, such as atmospheric CO2 and energy output of the sun. This is an active area of research and quite interesting, but does not really shed a great deal of light on modern global warming, which has unambiguously been demonstrated to be the result of increased atmospheric CO2.
On the other hand, the "skeptic" will reject the great mass of climate reconstructions (generally with ad hominem remarks about climate scientists or scientists in general), but will accept as gospel truth a just-published article that yields divergent results suggesting that temperatures in the past might have been higher than previous estimates. Similarly, the "skeptic" will enthusiastically embrace the "evidence" of third-hand accounts of medieval agricultural practices in northern europe as indicating that there was a warm period during medieval times--and conclude (in a bizarre jump of logic) that if medieval times were warm for some reason that (with our very limited information about climate drivers of the time) we don't understand, that we don't have to worry about the fact that we are currently seeing exactly the type of temperature increases that are predicted as a consequence of the CO2 that we are adding to the atmosphere.
Of course, a real scientist will have a very different reaction: We don't know if there was some unexplained process that warmed things up during medieval times--there isn't enough information to figure out for sure that that really happened, or if it did, what the cause was. But what if it did? That's even more disturbing. We know what the modern warming is due to--it's due to increased CO2. What if there is some other process that could produce a comparable warming in the absence of increased energy from the sun (because we've measured that, and we know it's not increasing)? Wow, that's really scary! What if that unknown process were to suddenly kick in on top of CO2? The projected warming from CO2 is bad enough, but add in some warming from some other unknown mechanism on top of that, and we could have a real catastrophe! This makes controlling CO2 even more important than I thought!
The planet has been cooling for the last 55 millions years and we are in an ice age that is getting colder in the long term. In the medium term we are in a warm interglacial and the temperature is cooling towards the next Milankovitch minimum in about 23,000 years. That is the trend you are seeing since Roman times. Without humans the planet would be cooling not warming.
Over the last century and half the climate has warmed as the the planet comes out of the Little Ice Age.
Over the last half a century you have AGW on top of the natural variations due to forcing by C02, Methane, Soot, reduction in SO4 and feedback from changes in water vapour in the atmosphere.
Over the last decade and a half the planet hasn't warmed because due to low solar radiation and less El Nino events.
No Nature doesn't care about us and will most likely freeze us to death. In the short term we may cook ourselves first though.