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Earth's Temperature at Highest Levels in 400 Years
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.'"
I'll bet it's warmer than it was 10,000 years ago, too.
"National Security is the chief cause of national insecurity." - Celine's First Law
You'd be right if that was what they said. But they didn't say that.
They said it was unprecedented within the last 400 years, at least. That's not the same thing.
Even if it were the warmest the earth has ever been
"Millions of years ago, the Earth was a great, molten mass, called Pangaea."
Unprecedented high temperatures in recent history, perhaps. Unprecedented in terms of Earth's history? I'm afraid not. 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".
__
Do ya feel happy-go-lucky, punk?
1. It wasn't this hot 400 years ago... we only have 400 years of reliable temperature data.
2. From the fucking article...
The best education consists in immunizing people against systematic attempts at education. - Paul Feyerabend
To: Guy with selective hearing.
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
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.
For those who want to bypass the dysfunctional reporting of the MSM, you can get the full report 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.
Ceci n'est pas une signature.
Actually he has...
And 'human influence' doesn't really matter, we are just as screwed if it is caused by sunspots or volcanos as if it were caused by human beings. In fact concentrating on that is likely to make things worse as it only furthers the delusion that we are the sole source of anything bad happening, and that once we all switch to driving hybrids the Earth's climate will magically remain the same for thousands of years.
Mathematics is made of 50 percent formulas, 50 percent proofs, and 50 percent imagination.
According to NASA the five warmest years on record are (in order) 2005 1998 2002 2003 2004
Dear "The Voice of Fairness and Reason,"
Download this: http://www.nap.edu/catalog/11676.html
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
Education is the silver bullet.
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
> I know a lot of people which can't agree on the causes.
f _the_past_1000_years
Then you know a lot of people ignorant on the topic. I was, too, until quite recently. We are well outside the normal zone of the typical cyclical temperature and CO2 variations, going back for hundreds of thousands of years.
> Temperatures were warmer 1000 years ago.
Uh, no, at least if Wikipedia is to be believed:
http://en.wikipedia.org/wiki/Temperature_record_o
Please to take note of when we started going well past that 1000 year temperature high. Go see "An Inconvenient Truth" while you're at it.
You seem to not understand the issue either. The question isnt wether or not the climate has changed before, its how drastic a change is potentially occuring now (now being relative = the past 100 or so years and into the next 100 or so years). The change is occuring VERY rapidly relative to anytime before (again period time, not say a volcanic winter type summer event), on a landscape that is VERY different then anytime before. For example species facing wheat fields and roads as well as oceans for blockades.
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). 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.
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 in full format, and a 4 page executive summary.
-Ted
-=-=- Quantum physics - the dreams stuff are made of.
Let us assume for a moment that the climate change is man-made. Let us further assume that all developed nations take immediate steps to completely eliminate their CO2 emissions. What will happen?
CO2 emissions will keep rising. China is building coal-fired power stations at a tremendous rate, and will probably keep doing so for a few decades, at least; India - which will have a larger population than China in a couple of decades - will be doing exactly the same thing. They're doing this because they need electricity to modernise their economies, and coal is both plentiful and cheap. Between them, they will probably pump out enough CO2 to fully compensate for the CO2 not emitted by the developed world.
Conclusion: it doesn't matter whether global warming is man-made or not. If it's natural, there's nothing we can do about it, and if it's man-made, it isn't going to be arrested any time soon.
So we are just going to have to live with the consequences.
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.
Uh, they would be right there on the chart on the page you linked to - the error is provided in gray. You'll note, as pointed out in the NAS report, that the errors are smaller for data since 1600 or so. Nobody is misrepresenting error tolerance here - it was calculated and is displayed clearly in the graphic.
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The chart at this site's page http://carto.eu.org/article2481.html , 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.
Yes, some glaciers are growing. However, the combined net change is a loss of glacial mass.
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. This obviously has a greater impact on the polar ice than a 1 degree rise would have had.
Stephan
The reality is that the number of "Scientist 1"s is about 100 times greater than the number of "Scientist 2"s. The news media just amplifies the voices of the "Scientist 2"s for the sake of "balance". Most of the scientific debate is within the "Scientist 1" camp regarding the specifics of global warming (how much is human produced, how disruptive will it be down the road, what options do we have for controlling it). However, that doesn't make for a nice, ratings-boosting shouting match on Crossfire.
Fact is that the Earth is, on the whole, warming. Evidence suggests that it's mostly due to human activity (although that's far from proven). It's a strong hunch that a warming Earth will disrupt human activity -- we can be fairly certain that rainfall will shift, which will move food production and cause economic upheaval, although climate is such a chaotic system that we can't really say where the shifts will be. It's a strong hunch that it will result in more frequent hurricanes, more powerful hurricanes, or both (more heat = more ocean evaporation = hurricane fuel), which we might or might not be seeing already. It's a weaker hunch that, once we reach a certain amount of warming, the climate will abruptly swing from its current state to a different one -- evidence shows that historically there have been two climate settings ("hot house" and "ice age", with a 10 C swing between global averages), all of human existence has been in an "ice age" climate, and the swing might be caused by carbon sequestering (which we're currently undoing by pulling fossil fuels out of the ground and burning them).
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This is somewhat happening in Europe. Here in UK we get charged tax based on how polluting our cars are. The more CO2 (and other factors), the more tax you pay.
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.
Have a nice day!
The hottest temperature in 400 years does NOT imply that it was this hot 400 years ago. It simply means that if we look at the records of the last 400 years, the hottest temperatures are right now. Furthermore, if we look at the records of the last 1000 years (which are a little harder to read since there are fewer means of cross-correlation), the hottest temperatures are right now. Please try to understand that these two statements do not, in any way, contradict each other.
Ben Hocking
Need a professional organizer?