Global Warming...Fact or Fiction?

**Monash** · 28 Dec 10,, 13:57

Originally Posted by gunnut

Half of North America and Europe is buried under snow. Damn this global warming.

Which in no way disproves the science involved in global warming. Anymore than trying to claim the recent run of very hot weather in Perth is proof positive that GW is occurring. It is any long term changes and trends in mean and modal temperatures that are important, not single daily, monthly or even yearly peaks or troughs that diverge from these averages.

Anyway as things stand our decendants might end up pining for some global warming since the best evidence indicates we are currently into the 12,000th year of the current 10-30k Intergalcial Period after which the next 100-150K Glacial Period kicks in. Glaciers in London Moscow and Washington anyone???

**~~Old Codger~~** · 28 Dec 10,, 18:16

Monash,

"the best evidence indicates we are currently into the 12,000th year of the current 10-30k Intergalcial Periodthe best evidence indicates we are currently into the 12,000th year of the current 10-30k Intergalcial Period"

I am amazed that anyone can claim such precision in measurement.

Who did the research and how did they arrive at it?

I have been expecting a surge in 'Global Cooling' and Mini Ice Age' scare reports as the AGW hysteria becomes more and more discredited as time goes by.

The IPCC, the CRU of the UEA, and of course komrade algore, have a lot to answer for in the waste of multi billions of needed dollars around the world.

At 71, I expect to see this craze finally consigned to the dustbin of history long before I die. I am confident I will.

OC

**Wooglin** · 29 Dec 10,, 18:11

Which in no way disproves the science involved in global warming.

Of course not. If you pay any attention to the media it's just the opposite in fact. Cold and blizzards are proof of AGW.

Anymore than trying to claim the recent run of very hot weather in Perth is proof positive that GW is occurring.

Nonsense. Hot weather is proof of AGW, just as cold weather is. All bad weather is proof of AGW. Don't you read the papers? Cold spells and hot spells, blizzards and colder winters and warmer winters, and more snow and less snow, and floods and droughts, and a cooling Antarctic and a warming Antarctic, dogs and cats living together....all proof of AGW! Seems the only weather that isn't proof of AGW is when it's sunny and 72 outside.

It is any long term changes and trends in mean and modal temperatures that are important, not single daily, monthly or even yearly peaks or troughs that diverge from these averages.

Oh...

Well....don't see much of a change over the last 450,000 years. Is that long enough?

**ArmchairGeneral** · 29 Dec 10,, 23:03

Originally Posted by Wooglin

Oh...

Well....don't see much of a change over the last 450,000 years. Is that long enough?

Too long. Come on dude, you know that chart is irrelevant to the question at hand.

**Monash** · 30 Dec 10,, 00:11

Originally Posted by Wooglin

Well....don't see much of a change over the last 450,000 years. Is that long enough?

Errr... actually the graph you produced does reveal significant long term changes in global temperature. Short of radical changes in solar output or an extreme change in the orbital dynamics of the Earth there are upper and lower limits to how hot/cold the planet can get. Fossil records indicate temperate conditions at the poles in previous epochs and other measurements indicate prolonged periods of extreme cold. The issue with "Global Warming" is not whether the Earth can/does/will ever get "hotter" its whether the current apparent increases in mean temperature are caused by human activity.

**Monash** · 30 Dec 10,, 00:57

Originally Posted by Old Codger

I am amazed that anyone can claim such precision in measurement.
Who did the research and how did they arrive at it?OC

OC,
In terms of precision the measurements quoted above are based on averaged results for numerous measurements taken over the past few decades by scientists using a variety of methods (e.g. carbon dating). Each of these measurements has an inbuilt (and internationally standardised) margin for error built into them i.e. each particular data point has a statistical range (plus or minus) of accuracy. For example temperature as measured by a particular device may be measured in degrees Celsius but that measurement will have an inbuilt margin of error say plus or minus .1 of a degree. I’m not a statistician so I can't explain it very well - I think I understand it. I just can't explain it very well (anyone up on their statistics like to help here please) .

So the figures above represent the best currently available averages for the time scales involved. When you think about it a measurement of 12000 years in a range of 10-30 thousand is not exactly super accurate, which is not surprising given the time scales and the complexities involved.

As for who take the measurements - geoscientists, geologists and physicists etc etc using the same methodologies and maths used to give us computers, atomic theory and space flight. All of whom are have to have received professinal recognition in their chosen fields. And barring the minority of global conspiracy fans out there I can’t see anyone believing that the Earths entire geologic history as we currently understand it has been deliberately misinterpreted by those involved in studying it.

**Wooglin** · 30 Dec 10,, 14:59

Originally Posted by Monash

Errr... actually the graph you produced does reveal significant long term changes in global temperature. Short of radical changes in solar output or an extreme change in the orbital dynamics of the Earth there are upper and lower limits to how hot/cold the planet can get. Fossil records indicate temperate conditions at the poles in previous epochs and other measurements indicate prolonged periods of extreme cold. The issue with "Global Warming" is not whether the Earth can/does/will ever get "hotter" its whether the current apparent increases in mean temperature are caused by human activity.

:smack:

No kidding? I guess you haven't been following this thread.

Anyway, you said:

It is any long term changes and trends in mean and modal temperatures that are important, not single daily, monthly or even yearly peaks or troughs that diverge from these averages.

And 450,000 years is certainly a long term to which we can compare the current warm period. Does the current warm period appear unique in any way? Have we exceeded natural variability in the last 450k years? Nope.

**Wooglin** · 30 Dec 10,, 15:02

Too long. Come on dude, you know that chart is irrelevant to the question at hand.

It is? What is the appropriate length of time we should be looking at then? 30 years?

Or were you being sarcastic?

**gunnut** · 30 Dec 10,, 19:05

Originally Posted by Wooglin

It is? What is the appropriate length of time we should be looking at then? 30 years?

Or were you being sarcastic?

The appropriate length of time is whatever we need to prove the earth is warming up...

Come on, man, get with the program here.:hammer:

**Wooglin** · 30 Dec 10,, 20:11

Originally Posted by gunnut

The appropriate length of time is whatever we need to prove the earth is warming up...

Come on, man, get with the program here.:hammer:

How about 10,000 years?

5000 years?

3500 years?

2000 years?

1000 years?

^from 1990 IPCC report

Ok, to hell with this...we need to rewrite some history here:

Ahhhh! There we go! See?...proof!!!

**Monash** · 31 Dec 10,, 03:05

Originally Posted by Wooglin

:smack:

No kidding? I guess you haven't been following this thread.

Anyway, you said:

And 450,000 years is certainly a long term to which we can compare the current warm period. Does the current warm period appear unique in any way? Have we exceeded natural variability in the last 450k years? Nope.

Actually I have been following the "thread" since joining WAB but I actually wasn't commenting on the "debate" so much as on one thread which (jokingly I assume) commented on the fact that one recent cold spell disproved what is called Global Warming (GW) Theory. My comments were directed towards the correct use of statistical data in a discussion NOT whether or not Earth is getting warmer due to rising greenhouse gas levels. The Earth has got warmer in the past and it has got colder that can’t be disputed. However extreme long term shifts in temperature have dramatic consequences for the all species on the planet regardless of whether those changes are manmade or not. As I said try living in a world where ice caps have spread down past the Great lakes and sea level have fallen dramatically. Alternatively try living in world where sea levels have risen and coastal plains have inundated. As a whole the biosphere ticks on but for individual species the changes are severe. Some can't cope and become extinct, others manage to muddle through - their range deceases but they "survive", others prosper and expand. Point being closer you are to the extreme ends of the spectrum the harder is on a larger number of species (including us).

Given the above even as a technic species given current world population levels the human race would have trouble coping with some of the predicted changes. Personally I'm not one in "the sky is falling camp" but based on the scientific consensus to date GW would appear to be an issue that should be addressed in a practical, carefully thought out manner.

If some people want to believe that GW is a conspiracy concocted by a global cabal of climatologists who all secretly hold shares in wind turbine companies that is their business. I however view it like taking out insurance. I insure my house not because I know it will burn down but just because it might. In any case changes in terms of oil and coal use will have to be long term because there is no way to stop using them overnight so (assuming current models are correct) we are stuck with some degree of warming anyway.

And finally if GW is all a great con the side benefits in terms of cleaner air and water from a shift to solar/wind/fusion/hamster on treadmill power etc) will be worthwhile. The end is not near.

Cheers

**ArmchairGeneral** · 31 Dec 10,, 03:38

Originally Posted by Wooglin

It is? What is the appropriate length of time we should be looking at then? 30 years?

Or were you being sarcastic?

No sarcasm, and it's not really a matter of time length, as long as you've got a 100 foot wide screen so you can display a 450,000 year timeline with enough resolution that the last 100 years are even visible. A one degree change over 5,000 years is essentially indistinguishable from a one degree degree change over 100 years on that graph.

Anyway, those other graphs you posted are rather nice, and very interesting (apart from the 1990 IPCC one; no numbers on the y-axis? :shudder: ). I hadn't seen the Ljungqvist and Loehle ones before.

I went looking for info on the Ljungvist paper, came up with this. The graphs on that post confused me a little, as their HadCRUT line seems to go much higher, up to approximately .8C instead of .5 like the Lungqvist graphs show, or, now that I look at it, .4 on the Loehle...and now I'm really confused. Maybe the last one is global HadCRUT instead of just Northern Hemisphere, that would make sense. But it doesn't explain the other discrepancy. Maybe the graphs in my link are actually going through 2007, instead of 2000? Doesn't look like it, though. And now I'm confused about Loehle again, since the HadCRUT there does go through 2007, and the anomaly is half of what I'm seeing in the my link, which looks like it only goes through 2000. Even if that's global instead of NH, that doesn't sound right.

The little graph that the HadCRU people themselves provide looks more like the ones you posted, somewhere between .5 and .6. Weird.

**gunnut** · 03 Jan 11,, 17:54

I now believe that AGW is real. It happpened. But due to the diligent environmental activists and the forward thinking Kyoto Protocol, we have managed to turn the tide and reverse the course. We can see the result in the colder than normal winter months and cooler than normal summer months over North America and Europe over the last few years. I think we should stop right here before we plunge the earth into another ice age. It's better to believe in the next ice age than not to believe in it. If we're right, we have time to save humanity from catastrophe. If we're wrong, we continue as normal. It's a small price to pay and the reward far outweighs that price.

**Ray** · 03 Jan 11,, 19:05

I am no scientist.

But I am not very comfortable about the various natural calamities taking place.

Queensland in Australia is under horrendous floods.

Poor chaps!

**gunnut** · 03 Jan 11,, 19:16

Originally Posted by Ray

I am no scientist.

But I am not very comfortable about the various natural calamities taking place.

Queensland in Australia is under horrendous floods.

Poor chaps!

Ray!!!! Welcome back sir! :cheers: