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Earth's Temperature at Highest Levels in 400 Years
Posted by
CowboyNeal
on Thu Jun 22, 2006 05:35 PM
from the hot-one-this-era dept.
from the hot-one-this-era dept.
thatguywhoiam writes "Congress asked, and the scientists have answered: 'The Earth is the hottest it has been in at least 400 years, probably even longer. The
National Academy of Sciences, reaching that conclusion in a broad review of scientific work requested by Congress, reported Thursday that the 'recent warmth is unprecedented for at least the last 400 years and potentially the last several millennia.'"
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2006 Was the Warmest Year Ever 782 comments
kpw10 writes "Dr. Jeff Masters from Wunderground has a great summary of this year's rather abnormal weather (his blog is the best source on the net for in-depth weather analysis). The post discusses some of the cyclical climate forces at work this year and compares this year's record temperatures to records from the past. There are some interesting differences, particularly in the extent of the northern hemisphere seeing record highs this year." From the article: "December's weather in the Northeast U.S. may have been a case of the weather dice coming up thirteen — weather not seen on the planet since before the Ice Age began, 118,000 years ago. The weather dice will start rolling an increasing number of thirteens in coming years, and an ice-free Arctic Ocean in summertime by 2040 is a very real possibility..." Here is the The National Climatic Data Center's report announcing the entry of 2006 into the record books.
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temperature (Score:5, Funny)
Re:hot air (Score:5, Interesting)
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Let's try this analogy (Score:5, Insightful)
Imagine I see a line of people going on and on, until that line bends around a corner. Now, let's say I tell you that I'm taller than everyone in that line until it bends around that corner. Would you necessarily conclude that immediately after it bends around that corner you'll find someone taller? Because that's the kind of logic you're applying here.
Now, let's imagine that you do claim that. I now find a way to see around that corner and find tham I'm taller than everyone I can see there until it bends around yet another corner. Will you know claim that this claim means that there's someone taller right around the next corner?
Has it ever been hotter than it is now? Absolutely. Were we here to suffer the consequences? No. Has it ever heated up this quickly before? Probably not since the Earth first coalesced.
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Re:temperature (Score:5, Interesting)
Hypothetical question for you, You're crossing a road, first thing in the morning. You're still maybe half asleep, late night and all that.
Suddenly you hear a noise. You look up from your reverie to find there's a huge great truck barrelling down the road toward you, horn blaring.
So what do you do? Do you think "Hmm, this is an rare scenario. The truck could exist, but I also have to consider that I may in fact be still asleep and dreaming this encounter. What data can I collect to determine if actiion is truly warranted in this case?"
Do you do all that, or do you get out of the frigging way first and then run your analysis? I bet I know what most of your ancestors did in analagous situations.
See, the thing is that science never proves anything. That's not a flaw in science, it's methodology. Scientists have long discarded modus ponens [wikipedia.org] as the logical basis for the scientific method, in favour of modus tollens [wikipedia.org]. What that means is that we don't try to prove things, because we recognise that we may not yet have all the facts. Instead we propose a explanation that seem to fit the facts and we try and disprove it.
The thing to note here is that if e wait for science to prove that global is happening, we'll still be waiting in billions of years time. Even if the Sun the should expand to swallow the earth and engulf us solar plasma, we;ll still be waiting, because that's not what scientists, do!
What they do do[1] is get out of the way of oncoming traffic.
If you want to be scientific about this, you need a counter theory, and it has to be falsifiable. There has to be a test we can conduct that to prove it wrong. Preferably one that doesn't involve waiting a thousand years to see if the climate flips state back to the Cambrian Era.
Give me a set of criteria that, if they are satisfied, you will regard as sufficent evidence for taking action against global warming and I will accept that you may have a pont. Otherwise, all you're doing is saying "Bah! Youse scientist dunt never nothing nowhow" only in an fancy accent.
Me, I vote we get out of the way of the truck
[1] On the whole, that is. I'm not counting absent mindedness, scientific tests of experimental traffc-proof suits, or Bruce Banner when he gets angry. I don't really think this weakens my argument.
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Re:temperature (Score:5, Insightful)
Who was alive 13.7 billion years ago to confirm the Big Bang, or, if you're a creationist, who was around 6000-odd years ago to confirm Genesis?
If you want to know where these claims come from, try finding out [wikipedia.org] instead of just rubbishing something you clearly don't understand.
Anyone who thinks we, as humans, are big enough to affect this God given Earth in a permanent way, has a blown up ego.
Sure. Thing is, I don't particularly care about this God-given Earth. As you say, it can take care of itself. In the event of e.g. nuclear armageddon, the planet would barely notice and would carry on spinning round the sun in much the same way. Why, it wouldn't even wipe out all life!
But that wouldn't be much consolation to the folk left crawling around in the glowing ruins of what were once cities, dying slowly of radiation sickness.
I don't know about you, but I'm actually kind of attached to human civilisation, and I'm pretty damn sure we, as humans, are quite big enough to do quite a bit of damage to that. For example, by use of the aforementioned nuclear weapons -- or, according to some scientists, by the effects of our actions on the environment.
Global warming, if true, probably won't wipe out life on earth. But it could make it pretty uncomfortable for an awful lot of humans. Again, I don't know about you, but as far as I'm concerned, that counts as a Bad Thing. Now, yes, fighting global warming would cost money, money which would be wasted if it turned out not to be true after all. But what I want to know is why so many people seem to think that this makes it stupid to spend that money. Nobody seems to have any problem with paying for health insurance (you have no proof you'll get sick!), or car insurance (you have no proof you're going to crash!), or house insurance (you have no proof you're going to be burgled!). So what's wrong with planet insurance?
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Re:temperature (Score:5, Insightful)
Being "apathetic" IS taking a position, it's supporting the current "going to hell in a handbasket" strategy. And the real case is, if you read this or any other FA in a scientific publication:
It's very much like the health issues of smoking. Billions of dollars spent lobbying to make it look as if there is doubt when the case is proved by any reasonable definition.
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Re:temperature (Score:5, Insightful)
- Scientist 1: Global warming is for real
- Scientist 2: Right, here's why
- Scientist 3: If that is true, X should happen...oh see, it does!
- Scientist 5: Oh, but Y does not fit...ih, once we correct for the measurement error, it does!
...- Scientists 900-1100: Let's summarize all this in a number of reports
- National academy of science: Let's also summarize this...oh look, the summaries agree!
- Paid shill: But duh! Erm...no, isnt!
Of course this still underestemiates the degree of work and scrutiny that has gone into our scientific understanding of global warming, but you get the idea.Parent
Re:temperature (Score:5, Informative)
This has caused a renewed intrest in Deisel, which has always been traditionally lower in its CO2 emmissions, and with Petrol Pumps now also using BioDeisel blends in their fuel, as a pilot (They cannot use 100% biodiesel, as most cars are not adjusted for that)
This policy means that you are not penalised for driving a desirable car, just penalised for driving a polluting car.
To give you an example, I own a Jaguar X-Type Deisel, a very desirable, and pretty powerfull, responsive car. Yet I pay less tax than some people who have a fairly ordinary car, simply because my car pollutes less than theirs.
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Queue up the proof by anecdote posts (Score:5, Funny)
Re:Queue up the proof by anecdote posts (Score:5, Funny)
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there's a lot of nonsense on both sides (Score:5, Insightful)
If you look at places like dailykos.com and other political proponents of "we need to do something", even mainstream ones like Al Gore, they're at huge odds with the scientific literature. For example, you now hear all sorts of nonsense about how increased hurricane frequency proves we need to do something, even though there is no evidence at all of a relationship (some scientists have hypothesized a relationship between warming and hurricane intensity---not frequency---but even that is highly speculative and not generally accepted).
In addition, I've heard claims that severe winters also support global warming, but the UN's general reports on the subject dispel that as a myth, and claim that global warming would result in, on average, slightly less severe winters. (Of course, severe winters don't *disprove* globl warming either---there are still plenty of year-to-year fluctuations even if the average is getting warmer.)
People are also conflating multiple trends. The important issue from a human-change point of view is the extent to which greenhouse gases and other human creations are changing climate. That's a separate question from the *aggregate* climate change. There *is* indeed good evidence for human-caused climate change, but it is still a separate question. For example, glacier retreat is often cited, but is largely a different phenomenon---Canadian glaciers have been retreating since about 1842, long before significant human-caused global warming. Current glacier retreat does appear to be caused or accelerated by global warming, but showing a picture of "glacier in 1840" and "glacier now" is just shady politics, when most of that recession happened from 1840-1930. And, of course, we should also take into account the estimates that about 30% of current warming is caused by an odd increase in solar output.
I think on the whole shoddy pro-global-warming argument is hurting the case. When the facts are on your side, there's no need to embellish them, and it damages credibility. This is why Real Scientists tend not to do it.
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sucks to be you if you live in the desert (Score:5, Insightful)
Oh, and with much of China and India either already a desert or turning into a desert due to deforestation thousands of years ago, it's not going to get any better for them.
The desert is actually spreading too - look at China in google earth and see how much of China is sand, and with hunter/gatherer populations foraging for food and fuel, animals eating every plant that springs up from the earth, and pavement being laid down everywhere to speed rain runoff and reduce the amount of water that saturates the soil - the situation looks bleak.
Seriously, I hate to sound like a tree hugging hippie, but if everyone in the world planted a few trees, I believe we could have a positive impact on the global climate
Editors, please post flamebait stories in the AM (Score:5, Funny)
I love the smell of burning karma in the morning... It smells like slashdot!
You want Flamebait? I got your flamebait. (Score:5, Insightful)
On the one side you have scientists with the historical and current data, and the liberals who cheer them on. On the other side you have those who say Global Warming is just made up by a conspiracy of scientists and liberals.
Discuss.
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Warmer than... (Score:5, Informative)
I'll bet it's warmer than it was 10,000 years ago [thinkquest.org], too.
Right, just past the mini-ice age.... (Score:4, Interesting)
Re:Right, just past the mini-ice age.... (Score:5, Informative)
No, actually, that is not true. If you look at the report, they say there is data of sufficient quality to say we are hotter than we've been in *at least* 400 years. Before that, there is less confidence in the measurable proxies of temperature, yet it still appears current temperatures are hotter than any time going back to 900 AD. The data for previous times are even less reliable, and thus being careful scientists, the NAS is not willing to make statements about those times.
I don't know of anyone that does not accept global warming (as in the warming of regions of the earth). I know a lot of people which can't agree on the causes.
So you know a lot of scientifically ignorant people. Let's say this again for those in the back of the class: "Greenhouse gases are accumulating in Earth's atmosphere as a result of human activities, causing surface air temperatures and subsurface ocean temperatures to rise." (From the National Academy of Sciences [wikipedia.org]). Or, if you prefer, "Human activities ... are modifying the concentration of atmospheric constituents ... that absorb or scatter radiant energy. ... [M]ost of the observed warming over the last 50 years is likely to have been due to the increase in greenhouse gas concentrations" from the IPCC [wikipedia.org].
Cyclical Global warming != greenhouse effect.
True, that is why really smart scientists spend time examining the effect of anthropogenic climate change as a separate thing from cyclic climate change.
Greenhouse gases effect may play a part
Substitute do for may, and you are right.
For your edification, the report is available [nap.edu] in full format, and a 4 page executive summary.
-Ted
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Some additional info (Score:5, Informative)
The chart at this site's page http://carto.eu.org/article2481.html [eu.org] , which is becoming a bit more frequently seen, shows the graph of C02 content in the atmosphere and temperature ranges over the last 400,000 years as derived from examining core samples, up to 1950. In that graph there is a strong corellation between C02 content and temperature change (increased C02 == increased temperature, etc.) The high point on the graph happened about 325,000 years ago when C02 content hit about 300 ppm.
In 1950 C02 content was around 285 ppm.
In 2006 C02 content was 383 ppm
That's nearly 100ppm greater than 56 years ago, nearly 83 ppm greater than the greatest peak currently recorded. We've had a 35% increase in CO2 content over the last 56 years. We're 28% above the previously recorded peak level from the last 400,000 years, and we're seeing record high temperatures for increasingly large spans of time into the past.
Given the nearly lock step relationship between C02 content and temperature change, the rate of increase and the extent of the increase over the last 56 years, and the absence of any other major contributor to CO2 content in the last 56 years, I find it really difficult to think that the human activities known to increase C02 emissions we've increasingly engaged in over the last 150 years have had little to nothing to do with the obvious increase in both C02 atmospheric content and resulting temperature/climate changes. The rate and amount of change seem to indicate that we're already beyond the normal range of variation, yet people still feel comfortable saying it's just the normal fluctuation of the planet's climate. I'd sincerely like to hear other viable explanations for the facts, but there haven't been any - the most well supported hypothisis remains that humans burning fossil fuels (in ever increasing numbers do to an also alarming rate of population growth) are truly affecting the climate.
What I'm also really curious about is why so many are so adamant about refusing to acknowledge what seems to be obvious, but that's a task for psychologists and philosophers I suppose.
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Baseline (Score:4, Interesting)
Interestingly, (Score:4, Insightful)
Weasel Words: Scientists vs. Politicians (Score:5, Insightful)
Suppose you ask the question: Is X happening?
When a scientist says that a phenomenon "X is probably happening", or "the bulk of the evidence indicates that X is happening", he means "I'm pretty damn sure about it, but because everyting in science is subject to further investigation, I'm open to hear evidence to the contrary."
When a lawyer says that "X is probably happening", or "the bulk of the evidence indicates that X is happening", he means "I haven't the foggiest idea, and I need wiggle room so I don't look like an idiot when someone who knows what he's talking about asks me."
Trouble starts when the two world views are mixed. The scientist hears the bolded words in his part of the speech -- and the politician hears precisely the opposite.
The qualifiers are necessary to the scientist, because they're part of why a theory is explanation falsifiable (and by extension, scientific). Science can't progress except for those areas in which there exists Reasonable Doubt.
The politician hears only the phrases "is probably" (as opposed to certainly), the "bulk of" (as opposed to all of the evidence), and the "indication" (as opposed to conclusive truth pounded out on the table before Judge and Jury) that something is the case. In an adversarial "justice" system, you can't use weasel words, because the holy grail is Proof Beyond A Reasonable Doubt.
And the planet burns because people who don't grok science prefer oratory.
What the hell, the dinosaurs died because they didn't understand science either.
Unprecedented? No. (Score:4, Informative)
Unprecedented high temperatures in recent history, perhaps. Unprecedented in terms of Earth's history? I'm afraid not. [daviesand.com] Notice the three sharp spikes occurring at roughly 130,000 year intervals. We started such a rise about 15,000 years ago, right at the expected time if the pattern repeats, but something levelled it off around present-day levels and has kept it there for the last 10,000 years. Whatever cause the levelling-out it wasn't humans, we weren't doing anything on a scale large enough to cause global effects 15,000 years back. If whatever it is stops, I'd expect global temperatures to spike by another 2-3 degrees C, then drop sharply to 4-6 degrees C below "normal".
The hockey stick (Score:4, Insightful)
Ah yes, the infamous hockey stick (the chart). It was what convinced me that global warming was human-caused. Until of course I found that when you put random data into the analysis, you got a hockey stick [lbl.gov].
What it comes down to is that more than 200 years ago we didn't have accurate temperature measurement. Everything before that is an educated guess. And the precision necessary to show a fractional degree of change is simply unattainable.
Where are the error bars on the hockey stick? It's shown as if we had exact data for the last 1000 years--which of course we don't.
Junk Science Clouding Real Theory (Score:4, Insightful)
The fact that this point is warmer then some other point in some arbitrary number of years means nothing. There have been literally countless points in time when you can point backwards and say that it has not been so warm for 400+ years. Any idiot can see that pointing out that we are in another of such periods where the last local max with 400 years ago is thoroughly and completely normal and uninteresting.
Flouting stupid statistics like this is what makes smart people believe that global warming is a crap political ploy by environmentalist/anti-globalist/leftists/exc. If your goal is to divide, crap like this is a great idea as it assures everyone that the opposing side are idiots who couldn't tell the truth if their life depended upon it. If your goal is to build a consensus and spawn action, throwing out junk science is a waste of everyone's time.
There are a lot of good reasons to believe that the Earth is heating in an appreciable way and that humans could very well be the cause of much of that heating. We don't need to throw out junk science and sensationalist crap like "OMFG hottest year in 400 years!" as any idiot with even an ounce of grey matter is going to realize that "hottest year in 400 years" is pretty damn normal during any heating phase, especially heating phases that happen on geologic time.
Reading the actual report is better than Yahoo (Score:4, Informative)
Now, notice something: we're talking about a "warming trend" over the last 400 years. That would be the interval from roughly the beginning of the "Little Ice Age" to now. So, in other words, we're now substantially warmer than the low point of a historically unprecedented low temperature interval.
Well, duh. Does the phrase "regression to the mean" ring any bells?
More
In other words, the conclusions of Mann et al. aren't very well supported --- and those are the ones most often used politically.
Get the NAS Report here (Score:4, Informative)
For those who want to bypass the dysfunctional reporting of the MSM, you can get the full report [nationalacademies.org] in PDF directly from NAS.
Also available from that link: The press release, audio of the press briefing, an abbreviated report and opening statement.
Stephen McIntyre offers interesting commentary on the report here [climateaudit.org].
P.S. (Score:5, Funny)
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Re:P.S. (Score:4, Funny)
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Re:To: Mr. George W. Bush (Score:5, Insightful)
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Re:To: Mr. George W. Bush (Score:4, Insightful)
If you believe the climate is stable, then of course it's bad! But we know better. Based on the data, we're towards the end of a brief (10k year) warm period toards the end of a 100k year warming cycle, but we're still in an ice age. We have 400k years of pretty good temperature and CO2 data now from the Vostock ice cores, and it's clear that a stable climate is an illusion caused by man's relatively short lifespan. This fact is as clear as the fact that global warming is happening.
So, let's assume that mankinds actions are capable of affecting the climate short term (for a few thousand years). Do we want to turn the thermostat up, or down, or try to keep global temperatures about the same? While the last option might sound good, trying to keep achieve stability in a chaotic system that we don't really understand and can barely model is probably pointless.
If we have to choose between sea level rising a bit, and glaciers covering England and most of Europe (on the upside, we'd lose Canada too), warming is probably a smaller problem to del with than cooling. Regardless of what we do, temperatures are certain to return to the ice-age norm long term (all the carbon in the air, water, and all fossile fuels still in the groud are completely trivial compared to the carbon cycle of the lithosphere), but that's a problem we can consider in another 10k years.
If you've never thought about global warming beyond "prevent climate change", you haven't really understood the issue. Preventing climate change isn't a long-term option.
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Re:To: Mr. George W. Bush (Score:5, Insightful)
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Re:To: Mr. George W. Bush (Score:4, Informative)
Scientists have proven that carbon dioxide emissions from human actions have caused the temperature of the Earth to increase. They have collected evidence which demonstrates this within the margins they find to be acceptable as proof.
Having proven it to other scientists, it is not their responsibility to now come to your house and prove it to you according to your rules, nor are they obligated to sponsor a cartoon version for your consumption. Every scientist who has studied this topic, and does not work directly for an oil company, has come to the same conclusion. There is more debate among experts about the validity of the proof of the Poincare conjecture than there is about the evidence for global warming.
However, I do not suspect that you will be persuaded by this. You will endlessly try to debate and complain about this, and you will simultaneously avoid actually studying the facts or researching more information.
You are ignorant by choice, and I hope you get full blown aids or melanoma.
Signed,
Another Guy
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Re:To: Mr. George W. Bush (Score:5, Informative)
Download this: http://www.nap.edu/catalog/11676.html [nap.edu]
Flip to page 103 for Figure 10-6: Model-based estimates of global sufrface temperature compared to observational estimates with contributions of natural (volcanic and solar) and anthropogenic forcings for 25-year periods shown as color bars.
The anthropogenic bar in the last 25 years totally dominates all of the other bars. I haven't read the entire article, but it sounds to me like you haven't even bothered to read any of it and yet you feel totally comfortable spouting off about it.
Scientists will never clame to PROVE anything, so stop using political motivations to attack scientific findings.
Signed,
The Voice of Telling You To RTFA
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Re:To: Mr. George W. Bush (Score:5, Informative)
Clue-bat: scientists don't try to prove things. Scientists have never tried to prove things. People who prove things are called logicians and mathemeticians, usually abstract math.
Instead, what scientists do is provide explanations for observations. If the explanation explains enough observations, the explanation becomes a "theory", defined as "A set of statements or principles devised to explain a group of facts or phenomena, especially one that has been repeatedly tested or is widely accepted and can be used to make predictions about natural phenomena."
(As opposed to a very different meaning of the word theory that is often incorrectly used by anti-science advocates: " An assumption based on limited information or knowledge; a conjecture.")
Proof is a mathematical concept. It isn't found in the real world. What is found is a quantity of evidence sufficient that it would be foolish to withold agreement. So, Mr. Fairness and Reason, what you're asking for doesn't exist. As such it's not very reasonable or fair to require it as some minimum threshold of something worth learning. But then again, perhaps that's exactly why you are the way you are...
Finally, it doesn't matter all that much if we're to blame. What matters is if we can alter current trends to prevent a forseeable worldwide ecological disaster. Unfortunately, humans lack the political will to prevent disaster (Katrina). Traditionally, we only act collectively to repair disasters. And for ecological disasters on this scale, the only thing that is clear is that by the time global warming really begins to hurt the wealthiest countries on the planet, there will be almost nothing anyone can do about it. As such, things are likely to get very, very bad before any substantive effort is made to change things.
Regards,
Ross
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Re:To: Mr. George W. Bush (Score:5, Interesting)
It's well past the time that we pick a problem, and all attempt to fix it.
We can all clearly that noxious emissions are a problem. In some parts of the world, they've pushed the oxygen levels in the atmosphere down to almost unsurvivable levels. Producing lethal chemicals and dumping them into the environment is also clearly bad.
Depsite these obvious problems that we continue doing, we'll argue the finer points of theory until we're dead.
Hell, what's the worst that cleaning up would do? Cleaner air and water? I wouldn't complain.
Many countries agree that there's a problem, and want to fix it. Read up on the Kyoto Protocol. The #1 producer in carbon emissions is also one of the two countries who have refused to agree to the protocol.
Token things are done to clean up the air. For example, passenger cars were required to meet stricter requirements. Unfortunately, trucks and SUV's don't fall into the same rules. Marketing went heavy into putting every Joe-Consumer and soccer mom into a SUV. There's bigger money in oil than there is in clean air.
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Re:No, some glaciers are growing. (Score:5, Informative)
A similar effect is true of global temperature. Despite global warming, there are areas of the earth that are coolear. However, the global average is up. Note that temperatures at the poles can be affected very dramatically, the average at the north pole by as much as 8 degrees [nytimes.com]. This obviously has a greater impact on the polar ice than a 1 degree rise would have had.
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Re:This just in . . . (Score:5, Insightful)
Now I'll tell you to look up the term Milankovitch Cycles and be done with you.
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Re:This just in . . . (Score:4, Informative)
"Millions of years ago, the Earth was a great, molten mass, called Pangaea."
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Re:This just in . . . (Score:5, Funny)
Errm... there wasn't anyone around to name the Earth anything a few hundred million years ago, unless you count the Vogons and the mice.
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Re:This just in . . . (Score:5, Insightful)
If you put it next to the age of the Earth, the meteorite-induced disruption to the world's climate that put the nail in the coffin of pretty much every large land animal on Earth (including the dinosaurs) doesn't seem that significant.
Nevertheless, to the dinosaurs it was pretty significant.
Likewise, the question with anthropogenic global warming and other alterations to the environment induced by man is not "are the disruptions a huge deal on a geological timescale", but "do the disruptions pose an intense danger to the continuation and quality of human life on earth." To which the answer, for global warming, seems to be a pretty clear yes.
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Re:This just in . . . (Score:5, Insightful)
But sure, let's sit back and watch what happens. Big experiment in social restructuring, could be fun. Could be hard for someone, but that's the breaks. And maybe in 100 years, after the migrations have started in earnest and whole continents empty into whole other continents, rivers of human flesh and misery passing each other in hopeless crawls from one ecological disaster area to another, maybe our grandchildren won't be digging up and violating our corpses in blind rage at how stupid and cynical we were at the very moment in 400 years of screwing up when we could have turned this ship around and saved them a lot of human misery.
Cuz you know, it's just 400 years of history. Blip in the continuum man. Not my problem.
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Re:What caused the warming 400 years ago? (Score:5, Informative)
They said it was unprecedented within the last 400 years, at least. That's not the same thing.
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Re:What caused the warming 400 years ago? (Score:5, Informative)
1. It wasn't this hot 400 years ago... we only have 400 years of reliable temperature data.
2. From the fucking article...
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Re:What caused the warming 400 years ago? (Score:5, Insightful)
As to the greenhouse gas hypothesis, there are a couple of real problems with it:
(1) about 60 percent of the temperature increase happened between 1500 and 1900. The notion that there was a lot of unusual greenhouse gases in that interval is questionable at best.
(2) there is significant data suggesting "global warming" of similar order of magnitude on Mars and other planets.
(3) most of the argument that greenhouse gases are causing the warming are based, first and foremost, on the assumption that there is unusual warming, which is not a very strong conclusion, as noted by the report. Reasoning from "there has been global warming" to "there is an anthropogenic reason for global warming" to "anthropogenic causes for global warming are proven by the global warming" is circular.
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Re:What caused the warming 400 years ago? (Score:5, Insightful)
The data shows a flat line for several hundred years, then a "hocky stick" increase coinciding with our use of fossil fuel, to use the term in TFA.
It's a little off to call those data. Those curves are reconstructions of temperatures from proxy data, like tree rings. What's more, as was pointed out above [lbl.gov], feeding statistically appropriate noise to the reconstruction methods used by Mann et al. rsults in a statistically indistinguishable "hocket stick."
Now, this doesn't mean there has been no warming --- in fact, we're pretty durn certain that it's warmer now than it was when Isaac Newton was alive. The Thames doesn't freeze solid like it used to. What it does mean is that the methods of Mann et al. can't distinguish data that shows warming from data that is uniformly random. In other words: warming, yes; hockey stick, no.
That is the crux of the issue.
Except for the part about "not true."
Now I know people who would probably fire back with the cliche "correlation doesn't imply blah blah blah", and then shut their brains off. The cliche is overused, and correlation ABSOLUTELY DOES point fingers at possible sources of the observed trend (that's called the Conclusion of the Results, or rather the interpretation of the experts).
Except the actual report doesn't say that.
The "actual interpretations of the experts" are that they have little confidence in the conclusion that global temperatures have actually increased dramatically or unexpectedly. (Again, that doesn't mean they haven't. It just means that we don't know, and the actual data and the reconstructions from the data don't tell us.)
Since NO OTHER MEASUREMENTS trend the same way, the choices are fairly limited as to what could be causing it.
On the contrary, since reconstructions of plain random numbers provide the same "hockey stick" results as the data, the reconstructions of Mann et al. don't actually tell us anything.
Sadly, I don't think four misstatements in four paragraphs is a
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Re:So... (Score:5, Insightful)
I know I'm anonymous coward, so it's harder to get the coveted +5 blessing, but really, sometimes the wisdom of anonymous cowards is better than the Wisdom of Cowards.
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Re:So... (Score:5, Informative)
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Re:So... (Score:4, Funny)
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Re:please (Score:5, Insightful)
If its A) and we worked on B), then we profit from less oil dependence and less smog, particulate matter,etc
If its B) and we assumed A), we all die.
Until we know more, I wish people would stop pretending they know what's happening. We have a couple theories, thats it, no proof. (correct me if I'm wrong)
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Re:please (Score:5, Insightful)
Well, correct me if I'm wrong, but the last time it happened the dominant life form wasn't industrialised and happily stuffing the atmosphere with greenhouse gasses
Thing is, it's going to be very difficult to remove greenhouse gasses and stop global warming in 100 years' time should the majority of climate scientists actually turn out to be right. It's really not going to hurt us that much to stop producing greenhouse gasses now, and it might even turn out to be the right thing to do. Why not do it?
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