Global warming date is from when?

[David H]

When predicting temperature rises for Earth, which year do scientists use as their base they will have risen from?

[rov1200]

They usually use graphs, sometimes with moving averages, to give a graphical picture over a number of years. Most climate change is cyclical but many of the recent publications are taken of the upward slant of the wave. If you look at this graph it covers over 2000 years and as you can see the cycle mirrors the climate in around 500 AD

http://images.google.co.uk/imgres?imgurl=http: //rebelliousvanilla.files.wordpress.com/2009/0 5/2000-years-of-global-temperatures.jpg&imgref url=http://rebelliousvanilla.wordpress.com/200 9/05/28/global-warming/&usg=__2p0PuVl58on6uIry i1sM0CfwZi8=&h=309&w=540&sz=43&hl=en&start=17& um=1&tbnid=ydjjUE0I5gKAgM:&tbnh=76&tbnw=132&pr ev=/images%3Fq%3Dglobal%2Bwarming%2Btemperatur es%26hl%3Den%26rlz%3D1T4GGLR_enGB286GB286%26sa %3DX%26um%3D1

[jake-the-peg]

Rov has either been selective or unfortunate in his choice of graph.

There are numerous ways of getting at historical temperatures so it is possible to pick the one that shows what you want to see.

You only get the best ifea by putting all the lines together and looking at them as a whole like this:

http://www.globalwarmingart.com/wiki/File:2000 _Year_Temperature_Comparison_png

If you look at the red line it's similar to Rovs - looking at them all together however you can see that the Earth's temperature now is much higher than it was in the medIevil warm period.

Being selective with the data is a classic trick of climate change skeptics sadly people often fall for it

[rov1200]

As these same scientists predicted we were heading for another Ice age just 30 years ago you can take your choice.

[Jumbuck]

Here's another one temperatures. Note that this one doesn't use the word reconstructed (i.e. we've made the data fit our conclusions).

Those that are so passionate that man-made climate changes are happening are just as guilty of manipulating the data as those against this theory.

[jake-the-peg]

Oh here we go again!

Am I going to have to spend another tedious day refuting all the same old Global warming myths?

Well at least the Royal Society ( the first and one of the most respected scientific institutions ) has done much of the work for me

http://royalsociety.org/page.asp?id=6229

I refer you to misleading argument number 1on their web page

I'm old enough to remember the "New Ice Age" story. That was put forward by a handful of reseachers on the sole premise that ice ages were cyclical and we hadn't had one for a while.

The papers ran with it and there were a couple of books.

Compare and contrast with the situation today where Global warming is acknowledged by pretty much every major scientific institution and supported by mountains of data.

Even George Bush accepted it in the end!

But Rov as I pointed out on a previous thread - if you really don't think Global warming is real there's a simple question you have to find a good answer to.

"Where are all the Glaciers going?!!"

[jake-the-peg]

And Jumbuck I refer you to:

Misleading argument 6 : It's all to do with the Sun

Do you guys really think that 99.9% of the worlds climate scientists are involved in a conspiracy to pervert and corrupt data and get the world to spend a fortune on preventative measures just to get extra funding.

I've worked in professional science and I can tell you that is the most delusional thing I've ever heard.

There have been a number of examples of scientific fraud in Korea and Germany. In both cases nobody could confirm the data and they were ripped apart

[jake-the-peg]

And Jumbuck

Check out who you get data from

These guys are not climatologists they are TV weathermen!!

http://www.longrangeweather.com/About-Us.htm

ROTFL!!

[Jumbuck]

Citing George Bush doesn't seem like a clever move for you.

And the cynic in me would suggest that:

a. doing research that supports populist theories = government funding

b. doing research that contradicts populist theories = banishment from the scientific community that form group a

When I was doing astrophysics research 30 years ago Hoyle and Wickramasinghe were proposing that life on Earth was started by the relevant molecules being delivered by comets and the astrophysical community just dismissed them out of hand as being a joke, to the point of doing research simply to prove that they were wrong ( I was one of those doing just that). And guess what, pre-life molecules have now been discovered in comets so it seems that they might have been right all along.

[jake-the-peg]

Bush is a good example as a skeptic with much to lose who was forced to accept the evidence

I think you're on dodgy ground quoting Pan-spermia.

I have a similar background and you know as well as I what a huge gulf there is between organic molecules and life!

Hoyle and Wickramasinghe were serious scientists - even with a minority view

Randy Mann and whats-his-name are TV weather men

[Jumbuck]

The point I was originally making was that graphs can be made to show whatever the person wants them to show; as for man-made global warming imho it's not proven so far - a lot of people see a bandwagon and just jump straight on.

H&W were in a minority of about 3 at that time.

And... are you a creationist?

[beso]

Where I live in Eastern Australia the skeptics have been very quiet the past week as we experience summer temperatures despite it still being winter.

New record August temperatues have been set across vast regions. Fires are already raging. Victorians are dreading the coming summer which is forecast to be even more incendiary than last summer where nearly 200 people died in huge fires.

Skeptics pretend there is still scientific debate but that is rubbish. Adding carbon dioxide to the atmosphere reduces radiation back into space. It can only get hotter.

The Arctic icecap is reducing by well more than 10,000 square kiolmetres each summer and it is thinner than ever. Wake up skeptics, this is real.

Realise that unlike other pollutants which can be removed reasonably rapidly from the atmosphere, the removal of carbon dioxide is very slow. Most of the carbon dioxide released in the 19th century is still heating us and will continue to do so for many hundreds of years.

Over half of the carbon dioxide produced by industrialisation has been released since 1976. And the rate of release still increases every year. The goals being set by the most radical of lawmakers are woefully inadequate.

[jake-the-peg]

If Jumbuck it's not proven in your opinion I think we have to ask the question ?

"What evidence would you need to be shown to convince you"

If you can't answer that you fail Popper's falsifiability criteria and we have to judge your opinion irrational

[rov1200]

As the skeptics say what caused global warming round about the year 1000AD. Too many bonfires I presume?

[David H]

All fascinating stuff and I'd suggest checking how icecaps are actually measured for a start as it's rarely reported that you can't tell the thickness of them from the air, you have to go and drill. This is what the Catlin project was for and the results are being analysed now. That's just a single example of only being given selected data on the news, but there is plenty more which is around but not given equal reporting status (by about 98%), so no wonder people like beso are panicking, that's exactly what they want to happen to try and stop any more questioning.

By the way, I only wanted a single date to tell me when they measure these predicted increases from, and the links haven't got a single date I could see. Clearly you need a base zero to extrapolate from, and am still waiting. There has to be one and if you all have as much trouble finding it as I am then it implies a lot of very important data is not indeed that easy to discover. I will let you all carry on debating why thay may be, but still need a simple year to answer my question.

[wildwood]

There is no set date. The temp started rising after the last Ice-age finished. The period of turnaround can not be dated accurately as even that takes centuries; the Poles will still be experiencing (very slight) cooling while the Equator is actually warming, even if only an minute amount.

I understand Global warming to mean the process whereby the planet's average temperature rise is accelerated through the atmosphere contamination in the last half century.

The (global) warming we now experience would in the natural process take millennia, not decades.
In my view this is potentially the most serious situation the Human race will ever experienced, much worse than the bubonic plague. Even a 20% reduction in production of pollutants will not make enough difference.

[jake-the-peg]

Rov, the sun's output does vary and that changes the climate nobody denies that.

This time however there is a difference.

All the previous changes are accounted for by the computer simulations. You know the cycles and they map to the temperature.

This time around it doesn't - the numbers only marry up if you take into account human Greenhouse gas emissions.

That's how we know and you have to do the numbers to see it - sitting around and saying "yeah but..." doesn't do it - you have to do the maths.

David, there are a number of base lines depending on the proxy being used. If you have human measurements (obviously the most reliable) you only have a hundred years or so.

Ice cores will have a different base line depending on where they're from and pollen records and geological data different again.

It's like using tree rings - you don't need a single tree to map thousands of years but by overlaying data from one source with another you get a continuous record.

That's why you need as much data as possible to iron out any inaccuracies or error. Hence the multi-line chart I posted the link to yesterday.

[rov1200]

David H you want a base temperature to show the changes in temperature. Mathematicians have a technique called regression towards the mean. That is the data below the line would roughly equal those above it. Therefore in this case you could plot a horizontal line and the temperatures below would sum up to those above.

[Slapshot]

In simple terms no one can talk about Climate Change with any definitive accuracy because every day new data challenges the allegedly well held theories of climate change, the Greenhouse effect etc etc etc.

Global heating and cooling are cyclic events and while we may have had time to analyse some of the data it will take decades to go back through data that will confirm what computer models suggest. There is little doubt that mankind has an effect on climate however there is no proven evidence as yet that categorically proves the net effects of man on climate and the long term effects of man's influence.

Global warming is a governmaent's way of increasing taxes to call the green taxes yet they do little with these funds, they are there to invest in research into new energy forms but generally pay off the national debt, welfare, defence and health budgets. The general media has helped enormously by hyping climate change beyond any hope of recovery, an alternative theory is put forward it's blasted to hell because governments need the hype to continue.
Follow up to come

[Slapshot]

�Global cooling is the dominant force controlling Earth�s climate change. Whenever the global cooling dynamo slows down, global warming occurs naturally.�

Inexorably linked to solar activities but if we didn�t have the greenhouse gases we�d be perpetually in conditions similar to Northern Canada. If it�s correct that the Earth would be perpetually cold without the greenhouse effect the engine generating the heat within the atmosphere is undeniably linked however, to what extent does this go to.

�Much of the fear surrounding the man-made global warming theory is associated with rising carbon dioxide levels. Current carbon dioxide level in the atmosphere as of January 2007 is 383 parts per million by volume. Atmospheric carbon dioxide levels have been accurately and meticulously measured beginning around the year 1812.

There are more than 90,000 accurate atmospheric carbon dioxide measurements made by various scientists and documented over the past 180 years. Most of these measurements were indiscriminately thrown out by the architects of the Man-Made Global Warming Theory.

Ernst George Beck recently reviewed these early measurements combining the results from several studies and his paper titled �180 years of Atmospheric CO2 Gas Analysis by Chemical Methods� was published in Energy & Environment, 2007, Volume 18, Number 2.