The coming ice age?

[disarray]

look familiar? guess whats next

 

[metric]

Mont Blanc glacier almost doubles in size
in four years
.

15 Oct 07 - That’s what the headline should have said. Instead, it shouted "Global warming makes Mont Blanc grow," in what I consider a blatant attempt to hide the truth. A different paper entitled the story "Climate change making Mont Blanc even higher."

Here’s how the stories went:
"Mont Blanc, the highest mountain in France and western Europe, has grown more than two metres in two years ... ironically as a result of global warming."

"Generations of French schoolchildren were taught the famous peak was 4,807 metres tall, but it has been growing since 2003 and at a faster rate in recent months.

Now let’s get down to the truth:

"The volume of ice on Mont Blanc's slopes over 4800 metres high was first calculated at 14,600 cubic metres in 2003. It dropped to 14,300 cubic metres two years later, but then almost doubled to 24,100 cubic metres in 2007.

It's size almost doubled in four years!

Such "growth" in mountains is specific to higher Alpine peaks, said Yan Giezendanner, a meteorologist."Glaciers at high altitude seem to be growing, while those situated at mid or low altitude are melting, shrinking and threatened with extinction," he said.

You decide. Were those headlines honest?

http://www.iceagenow.com/Mont_Blanc_glacier_almost_doubles_in_size.htm

 

[Plasmo]

http://environment.newscientist.com/channel/earth/climate-change/dn11650


gee Plasmo - you claim that the IPCC didn't mention solar activity
How hard did you try before you made that incredible claim ?
I mean - here's what happens when you go to wikipedia .
http://en.wikipedia.org/wiki/IPCC_Fourth_Assessment_Report

Gee whiz 2020Hindsight, thanks for linking me to a writeup on "solar forcing". I wonder if "solar forcing" and "sunspots" are the same thing.

Oh wait, they aren't. So my point still stands, and you should please find out the difference between the two before continuing to talk about global warming.

 

[Superfly]

Please this must stop... do not ask the left hard questions, you are not meant to do that, just accept GW as truth...global warming... global warmimg.. Bush is bad... Bush is bad... Rudd is good.. Koyoto is good... rah rah rah ...

 

[metric]

below is a whinge by the rabidly partisan, rabidly green, agenda driven, bubble gum scientists....

http://www.abc.net.au/news/stories/2008/04/24/2225980.htm

Ice age claim angers scientists
By Emily Bourke

Posted Thu Apr 24, 2008 8:42am AEST
Updated Thu Apr 24, 2008 8:51am AEST


A former NASA astronaut fears Earth could be headed for a new ice age. (File photo) (AAP Image: Simon Mossman)

Audio: Former astronaut warns of new Ice Age (PM) Audio: Full Interview with Dr Phil Chapman (PM) Related Story: Make a stand for good science It might be an unpopular view but Dr Phil Chapman is sticking to it. The geophysicist and former NASA astronaut says figures from four separate agencies show the global temperature dropped noticeably during 2007 and that the globe could now be returning to an ice age.

"All the people who monitor the world's global temperature say that the temperature fell by something like 0.7 degrees Centigrade," he told PM.

"We're talking about a very large drop that cancels out all the increase since 1930.

"If this continues, then global warming will have to be, we'll have to admit that it's over."

He says the sun and sunspot changes have a bigger influence on the climate compared to carbon dioxide.

"The variations in the number of sunspots and the time when they occur, how rapidly they build up, has a close correlation with previous changes in climate, in particularly back around 1700 and again around 1790 when the sunspot cycle was delayed and those were two times it was extremely cold," he said.

So can you see a repeat of that happening now with the few number of sunspots that have been detected?

"It's that coincidence between sudden rapid drop in global temperature in the last year and the lack of sunspots which makes it seem a little worrying," he said.

While he won't commit to a date, Dr Chapman says an ice age is on the horizon.

"If the ice age comes, it will come, it certainly will come but we don't know whether it's started already or whether it is going to be a thousand years from now, we're probably OK but you can't be certain, that's all," he said.

Dr Chapman says it is hard to think of what the world can do, other than trying to warm the planet.

"I think we should have an open mind on the subject and not rush around doing things on the assumption that it's going to get warmer when in fact it's going to be cooler," he said.

"It may be that we should be pumping out all the carbon dioxide we possibly can in order to try and keep the temperature up."

David Karoly from Melbourne University's School of Earth Sciences is outraged.

"This is not science. This is misinterpretation or misrepresentation and mis-communication of the factors that influence global temperature," he said.

"It appears to be an opinion of Phil Chapman and he's welcome to his opinion, but in terms of climate variations and an approaching ice age, he is sadly misinformed.

"Yes, the climate system did cool from January 2007 to January 2008 quite dramatically. That cooling was associated with changes in the ocean temperatures in the Pacific, a well known phenomenon, the El Niño to La Nina switch. It isn't unprecedented."

But he says it is not due to sunspot activity.

"Sunspot variations do not lead to the sorts of temperature variations seen from January 2007 to 2008," he said.

"They don't lead to those large temperature variations, even on an 11-year sunspot cycle.

"And so in terms of increasing greenhouse gases, we can also see that effect because the most recent La Nina, the current La Nina, is warmer than earlier La Nina episodes of the same strength.

"We're actually seeing a warming even in these cool periods associated with La Nina."

Dr Graeme Pearman is a climate scientist and past chief of atmospheric research at the CSIRO.

He says the doubt over global warming and its causes is not reasonable and he warns Dr Chapman's wait-and-see approach is dangerous.

"And what science has seen over the last six months or so are changes that are occurring that are further advanced than we would like," he said.

"And so I think there is a high probability, a much higher probability than his scenario coming true, that we're going to look back and rue the fact that we didn't act earlier.

"We must get on with trying to slow down the growth of our emissions as a global community and as an Australian community as soon as possible."

 

[2020hindsight]

Global warming true believers have spent the last few years denying that sunspots affected global temperature, because admitting this fact would undermine all the "models" attributing historic temperature rises to CO2.

Gee whiz 2020Hindsight, thanks for linking me to a writeup on "solar forcing". I wonder if "solar forcing" and "sunspots" are the same thing.

Oh wait, they aren't. So my point still stands, and you should please find out the difference between the two before continuing to talk about global warming.

groan

Plasmo, "forcings" in this case include natural forcings such as solar activity, volcanic ash etc , and also manmade forcings such as CO2. You’ll see solar radiance amongst the bars of that chart I posted from that wikipedia link.

http://environment.newscientist.com/channel/earth/climate-change/dn11650

Recent rises
Despite these problems, most studies suggest that before the industrial age, there was a good correlation between natural “forcings" – solar fluctuations and other factors such as the dust ejected by volcanoes – and average global temperatures. Solar forcing may have been largely responsible for warming in the late 19th and early 20th century, levelling off during the mid-century cooling.

The 2007 IPCC report halved the maximum likely influence of solar forcing on warming over the past 250 years from 40% to 20%. This was based on a reanalysis of the likely changes in solar forcing since the 17th century.

But even if solar forcing in the past was more important than this estimate suggests, as some scientists think, there is no correlation between solar activity and the strong warming during the past 40 years. Claims that this is the case have not stood up to scrutiny.

Direct measurements of solar output since 1978 show a steady rise and fall over the 11-year sunspot cycle, but no upwards or downward trend.
Similarly, there is no trend in direct measurements of the Sun's ultraviolet output and in cosmic rays. So for the period for which we have direct, reliable records, the Earth has warmed dramatically even though there has been no corresponding rise in any kind of solar activity.

I thought your point was that IPCC (and other true believers) never considered , - or were reluctant to consider - variations in solar radiance. yes? But it’s just sunspots yes? No, that doesn’t make sense, because your first post was either
a) sunspots , or
b) CO2.

So I assume you are not trying to split hairs between “sunspots” versus “general solar activity”.

You'll also see (above - and as previously posted in my reply to your post) that the IPCC take solar radiance into account. - albeit they downplay the effect somewhat compared so some others. (20% as against 40% etc respectively). They have reasons for doing this – which I can either post or let you research. Maybe I’ll post them later.

But rest assured that the IPCC as well aware of the role of the sun in all this.

http://environment.newscientist.com/channel/earth/climate-change/dn11650

Switch off the Sun and Earth would become a very chilly place. No one denies our star's central role in determining how warm our planet is. The issue today is how much solar changes have contributed to the recent warming, and what that tells us about future climate.

The total amount of solar energy reaching Earth can vary due to changes in the Sun's output, such as those associated with sunspots, or in Earth's orbit.

there’s a graph there – all about sunspots – you ‘ll like it.

“Even if sunspot activity has been exceptionally high over the past century, as the reconstructed sunspot number suggests, this still cannot account for the recent warming.

Finally can I assume take it you will withdraw your statement that the IPCC have never considered sunspots / solar activity.

 

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considering todays weather patterns are much cooler than in previous times in history, some 6 deg cooler, GW (even if it was true) is of no consequence to the survival of the bears. otherwise, why havent they died out in the many tens of thousands of years when it was hotter than now? are they not genetically adapted to handle warmer conditions??? of course!!! but the GW deciples love to keep throwing the polar bear image at us.....

Polar bear in trouble, not endangeredBy Randall Palmer in Ottawa
April 26, 2008 08:23am

THE polar bear, the symbol of the effects of climate change on the sensitive Arctic environment, is in trouble but it is not endangered or threatened with extinction, an advisory panel says.

The Committee on the Status of Endangered Wildlife in Canada gave the polar bear its weakest classification, that of "special concern", but the Canadian government would nonetheless have to develop a management plan to protect the animals if it agreed with the new label.

"Based on the best available information at hand, there was insufficient reason to think that the polar bear was at imminent risk of extinction," Jeffrey Hutchings, chairman of the independent committee said after the panel met in the Northwest Territories.

"That's not to say that it's not in trouble. A special-concern species is a species at risk in Canada and requires legislative action should the government decide to include this species on the legal list."

Canada has an estimated 15,500 polar bears, or roughly two-thirds of the global population. Disappearing summer sea ice is causing a decline in numbers in some areas, but other regions are stable and in some the population is rising.

Mr Hutchings said that in addition to global warming, overhunting and oil and gas activity were also pressuring the population of the world's largest land carnivore.

Environment Minister John Baird, who has three months to decide on a response to the committee's report, said the polar bear was "an iconic symbol of Canada" and that Ottawa should not wait until the animal got a "threatened" designation.

"Let's take action now, and that's exactly what we're going to do," he said, standing in front of a stuffed polar bear at the Canadian Museum of Nature in Ottawa.

"We don't want to simply wait another five years for another report to say that proactive measures and action is needed. Obviously today's report says we need to do that now."
The stronger "threatened" status, if adopted, would have required prohibitions like bans on hunting and destruction of habitat, but Canada's Arctic Inuit people say restricted hunting should continue.

The US Fish and Wildlife Service has proposed listing the polar bear as a threatened species but has declined so far to formally do so. Mr Hutchings said he understood it had postponed its decision till the end of June.

The US Geological Survey said last September that two-thirds of the world's polar bears could be gone by mid-century if predictions of melting sea ice hold true.

The Canadian environmental group David Suzuki Foundation said five of Canada's 13 polar bear populations were thought to be in decline. The western Hudson Bay population declined by 22 per cent between 1987 and 2004, it said.

The group called for tougher action to combat global warming in addition to a formal listing under the Species at Risk Act.

 

[Plasmo]

groan

Plasmo, "forcings" in this case include natural forcings such as solar activity, volcanic ash etc , and also manmade forcings such as CO2. You’ll see solar radiance amongst the bars of that chart I posted from that wikipedia link.

http://environment.newscientist.com/channel/earth/climate-change/dn11650


I thought your point was that IPCC (and other true believers) never considered , - or were reluctant to consider - variations in solar radiance. yes? But it’s just sunspots yes? No, that doesn’t make sense, because your first post was either
a) sunspots , or
b) CO2.

So I assume you are not trying to split hairs between “sunspots” versus “general solar activity”.

You'll also see (above - and as previously posted in my reply to your post) that the IPCC take solar radiance into account. - albeit they downplay the effect somewhat compared so some others. (20% as against 40% etc respectively). They have reasons for doing this – which I can either post or let you research. Maybe I’ll post them later.

But rest assured that the IPCC as well aware of the role of the sun in all this.

http://environment.newscientist.com/channel/earth/climate-change/dn11650



there’s a graph there – all about sunspots – you ‘ll like it.


Finally can I assume take it you will withdraw your statement that the IPCC have never considered sunspots / solar activity.

Learn the difference between radiative forcing and sunspot activity's direct impact on global temperature. Then get back to me. It isn't my job to educate people who are deliberately impervious to learning about something that would contradict their worldview.

It isn't a matter of "splitting hairs", sunspots have a far greater impact on global temperature directly than they do via their contribution to radiative forcing.

And no, the IPCC has not considered this impact.

 

[2020hindsight]

Learn the difference between radiative forcing and sunspot activity's direct impact on global temperature. Then get back to me. It isn't my job to educate people who are deliberately impervious to learning about something that would contradict their worldview.

It isn't a matter of "splitting hairs", sunspots have a far greater impact on global temperature directly than they do via their contribution to radiative forcing.

And no, the IPCC has not considered this impact.

okok - so you ARE splitting hairs between sunspots and solar activity
(despite the fact that warming - according to one of your posts - was either due to
a) sunspots, or
b) CO2)

Furthermore, it would appear that you are talking in riddles, keeping your cards to your chest so you change the argument to suit.

Let's just admit that IPCC are onto solar radiance. .....

The consensus position (as represented for example by the IPCC Fourth Assessment Report) says that solar radiation may have increased by 0.12 W/m ² since 1750, compared to 1.6 W/m ² for the net anthropogenic forcing.[81] The TAR said, "The combined change in radiative forcing of the two major natural factors (solar variation and volcanic aerosols) is estimated to be negative for the past two, and possibly the past four, decades."

... then move onto other secondary effects of sunspots - I'm gonna guess that you're talking the effect on cosmic rays ok

- increase in sunspot activity causes increase in sun's magnetic field, decrease in cosmic rays hitting earth, POSSIBLE (argued) reduction in cloud formation, POSSIBLE more heat.

http://environment.newscientist.com/channel/earth/climate-change/dn11651

Climate myths: It’s all down to cosmic rays

Increased sunspot activity is known to strengthen the Sun's magnetic field, which deflects more of the galactic cosmic rays entering the solar system and thus reducing the number hitting Earth. The argument championed by Henrik Svensmark is that this would reduce cloud formation in the atmosphere – warming the Earth – and that this effect explains the recent global warming.

The case has been made at greater length in a book Svensmark wrote with science journalist Nigel Calder (who edited New Scientist from 1962 to 1966), called The Chilling Stars.

There are at least three separate issues here. First, do cosmic rays really trigger cloud formation? If so, how do the resulting changes in cloud cover affect temperature? Finally, does this explain the warming trend of the past few decades?

Far-fetched concept
There is no convincing evidence that cosmic rays are a major factor determining cloud cover. The ionising of air by cosmic rays will impart an electric charge to aerosols, which in theory could encourage them to clump together to form particles large enough for cloud droplets to form around, called "cloud condensation nuclei".

But cloud physicists say it has yet to be shown that such clumping occurs. And even if it does, it seems far-fetched to expect any great effect on the amount of clouds in the atmosphere. Most of the atmosphere, even relatively clean marine air, has plenty of cloud condensation nuclei already.

A series of attempts by Svensmark to show an effect have come unstuck. Initially, Svensmark claimed there was a correlation between cosmic ray intensity and satellite measurements of total cloud cover since the 1980s – yet a correlation does not prove cause and effect. It could equally well reflect changes in solar irradiance, which inversely correlate with cosmic ray intensity.

Furthermore, this apparent correlation depended on adjustments to the data, and it does not hold up when more recent cloud measurements from 1996 onwards are included.

In short, I think you'll find that the IPCC are onto sunspots in every conceivable interpretation thereof.

 

[Plasmo]

Wow you've gone from knowing nothing about sunspots to being an expert on what they can and can't do in the space of 30 seconds googling for any articles you can find to support the preexisting opinion you held. I bow to your wisdom and expert knowledge.

In short, I think you'll find that the IPCC are onto sunspots in every conceivable interpretation thereof.

Show me where.

 

[noirua]

The polar icecaps are not decreasing everywhere. Infact, they are increasing in places.
When the ice age cometh everyone will have left Planet Earth by then, and most planets will have declared their Independence.

 

[2020hindsight]

youve goota watch this youtube video. part 1 of 4. i doubt you will believe the rubbish that is GW after this..

http://www.youtube.com/watch?v=FOLkze-9GcI

the other 3 are at link..

metric , I believe I may have been the first to post those youtubes.
I also posted the contribution of Prof Bob Carter to that ABC global warming debate - compared to IPCC's Prof David Koroly - maybe you watched them as well

https://www.aussiestockforums.com/forums/showthread.php?p=277521&highlight=carter#post277521

https://www.aussiestockforums.com/forums/showthread.php?p=277528&highlight=carter#post277528

https://www.aussiestockforums.com/forums/showthread.php?p=277569&highlight=carter#post277569

For the best summary of all ( imo) watch the first 3m30s of this one ...

"Nick Rowley, Climate Change Strategist" - of UK gives a great summary...
balancing the risks of getting this wrong

on the subject of observed global warming , if you look at the great bulk of the world's climate scientists, around 98% of them really accept that basic science, - that is as close to certain - almost - as you can get - in relation to science.

Yet there are uncertainties, essentially about the future - and a future prediction is always going to be uncertain - and that's why, when you look at the IPCC reports, you have scenarios - lower, middle, and upper scenarios - and for mine, I very much hope they are wrong .

I very much hope we don’t HAVE a problem. But I think when you look at the balance of evidence, we DO. So when you look at those scenarios, and where we are travelling in relation to that warming , where it actually gets scary is not with the warming effects, it's with the severe climate effects are going to be of that warming.

And that's when we had briefings - from major scientists and others - at 10 Downing St, THAT's when it gets very frightening. That's when scientists actually become ashen faced. , and say "well, I can't really say what is really gonna happen with THAT amount of carbon in the atmosphere, and THAT amount of warming, and therefore what's gonna happen with respect to severe weather.

THat's when this issue is not actually about science.

It's about security
It's about economic security
It's about our physical security
in relation to the human population movements that may well occur IF the future predictions prove even half right.

 

[metric]

The polar icecaps are not decreasing everywhere. Infact, they are increasing in places.
When the ice age cometh everyone will have left Planet Earth by then, and most planets will have declared their Independence.

im for a commonwealth of planets, a monarchy, and the westminster system. with one change. i want paris hilton as queen.....

 

[2020hindsight]

Wow you've gone from knowing nothing about sunspots to being an expert on what they can and can't do in the space of 30 seconds googling for any articles you can find to support the preexisting opinion you held. I bow to your wisdom and expert knowledge.

Show me where.

My existing opinion of this argument is that it's going nowhere - you don't seem to want to tell me what you know about anything -

also it's a bit like the two old cricketers arguiing -

"what's the most runs you ever made ?
"124"
"ahh - I got 128 once - what about the most wickets you got bowling... "
"ahaha - no way, this time I go first".

PS are you talking solar radiance?
are you talking cosmic rays?
are you talking freckles?- who knows.

 

[2020hindsight]

I posted this on another thread where people were asked "global warming -how valid and serious?" - where incidentally 83% (at least) agreed that we should act to do something about global warming.

Nice summary of the science.
BUT even if you don't believe the manmade contribution to GW, I still think we should follow Sterns and Garnaut - call it the cautious route (and probably least expensive in the long term). and/or follow Nick Rowley (back a couple of posts) who says it is now about security.

Sir David Attenborough: The Truth About Climate Change

Garnaut :- "There will be winners and losers out of the big changes we are going through - We can make ourselves winners if we embrace innovation .... if we prepare ourselves for it - and that involves education planning strategic thinking.. good policy...

"Australia has not done particularly well over the last decade. Fortunately the States kept moving on climate change policy, even when the Federal Govt went through a period of scepticism (under Howard)."

Professor Ross Garnaut - Victorian Climate Change Summit

 

[Smurf1976]

The whole greenhouse effect / global warming / climate change / coming ice age thing has ceased to be a legitimate scientific debate quite some time ago in my opinion.

It is now a political debate just like ends up happening with every other environmental issue - for practical purposes the science stops the day it hits the headlines and politics takes over.

It's been exactly the same with every major environmental issue I can think of with one notable exception (ozone). Other than that, it's always the same. The science starts, then the media gets hold of it and from that point on any scientific or other factual argument is totally irrelevant. Pulp mills, forests, dams, uranium - all the big environmental debates have gone this way with politics taking over from science and the climate issue has now gone exactly the same way.

 

[metric]

The whole greenhouse effect / global warming / climate change / coming ice age thing has ceased to be a legitimate scientific debate quite some time ago in my opinion.

It is now a political debate just like ends up happening with every other environmental issue - for practical purposes the science stops the day it hits the headlines and politics takes over.

It's been exactly the same with every major environmental issue I can think of with one notable exception (ozone). Other than that, it's always the same. The science starts, then the media gets hold of it and from that point on any scientific or other factual argument is totally irrelevant. Pulp mills, forests, dams, uranium - all the big environmental debates have gone this way with politics taking over from science and the climate issue has now gone exactly the same way.

sounds like youve found a cure smurf!!!

 

[2020hindsight]

1. considering todays weather patterns are much cooler than in previous times in history, some 6 deg cooler, GW (even if it was true) is of no consequence to the survival of the bears.

2. otherwise, why havent they died out in the many tens of thousands of years when it was hotter than now? are they not genetically adapted to handle warmer conditions??? of course!!! but the GW deciples love to keep throwing the polar bear image at us.....

1. "much cooler than in previous times in history, some 6 deg cooler" (??) what the hell have you been smoking metric.? It is about as hot, possibly hotter now than in the last 2000 years (at least).

2. (they will probably survive as a species - albeit they'll be decimated - therefore stop "throwing the polar bear image at us !"

3. ..."insufficient reason to think that the polar bear was at imminent risk of extinction," - yeah, very comforting..

4. "That's not to say that it's not in trouble. A special-concern species....at risk.. requires legislative action." - ok - I think he's conceding some potential unease here - I think he's still saying there's nothing to worry about - (provided enough greenies heed the cause and overcome a pathetically apathetic public, and/or the gun lobby).

4. "Disappearing summer sea ice is causing a decline in numbers in some areas, but other regions are stable and in some the population is rising." I read recently that the areas that are increasing are where hunting has been restricted.
....
5. "Environment Minister : " Ottawa should not wait until the animal got a "threatened" designation." - "Let's take action now, and that's exactly what we're going to do," he said, standing in front of a stuffed polar bear at the Canadian Museum of Nature in Ottawa. "

A much less ambiguos statement yes? Let's take action - presumably before thousands more are also stuffed.

6. "We don't want to simply wait another five years for another report to say that proactive measures and action is needed. Obviously today's report says we need to do that now." .. Here Here. - gee whiz, 5 years to get some action would be brilliant - took Howard and Costello 10 years to even say the words "Climate Change" :2 twocents

"The stronger "threatened" status, if adopted, would have required prohibitions like bans on hunting and destruction of habitat" .... makes sense to me. - on both grounds, less hunting, and more habitat.
.....
7. "The US Geological Survey said last September that two-thirds of the world's polar bears could be gone by mid-century if predictions of melting sea ice hold true. " - hell only 2/3rd gone! - what are we worried about?.

8. "The Canadian environmental group David Suzuki Foundation ... The western Hudson Bay population declined by 22 per cent between 1987 and 2004, it said. (other areas protected by scaled down hunting). The group called for tougher action to combat global warming in addition to a formal listing under the Species at Risk Act"

Once again, David Suzuki shines out amongst men.
(just as when he recently said that politicians who didn't act on GHG and GW should be held legally liable).

Arctic specialist Mark Serreze said, following the record low in 2007,[102] "If you asked me a couple of years ago when the Arctic could lose all of its ice then I would have said 2100, or 2070 maybe. But now I think that 2030 is a reasonable estimate

http://en.wikipedia.org/wiki/Image:2000_Year_Temperature_Comparison.png

 

[2020hindsight]

The whole greenhouse effect / global warming / climate change / coming ice age thing has ceased to be a legitimate scientific debate quite some time ago in my opinion.

.. It's been exactly the same with every major environmental issue I can think of with one notable exception (ozone).

smurf - how do you know it's not another ozone?

PS just as well CFC's were (sorta) banned - or else we'd really be in a pickle on the GHG stuff

 

[2020hindsight]

1. "much cooler than in previous times in history, some 6 deg cooler" (??) what the hell have you been smoking metric.? It is about as hot, possibly hotter now than in the last 2000 years (at least).

http://en.wikipedia.org/wiki/Image:Holocene_Temperature_Variations.png
the light blue line shows results from a Greenland ice core - so for the purpose of discussing polar bears I suppose we should use that for comparison - and it seems it was hotter about 2500 years ago.

However it would seem that the mean Earth surface temperature (the dark line) has not been this hot for a long long time - i.e. 10,000 years and some - way back before the last ice age.

(light blue) GISP2 ice core, interpreted paleotemperature, Greenland: [abstract] [DOI] Alley, R.B. (2000). "The Younger Dryas cold interval as viewed from central Greenland". Quaternary Science Reviews 19: 213-226.

http://www.globalwarmingart.com/wiki/Image:Holocene_Temperature_Variations_Rev_png