Editorial: The Great Global Warming Hoax?

[shoggoth]

WIP posted from a link:

Sure 10 years is a short trendline.

The problem AGW believers has.Is that all the while CO2 goes on up,temperature does not.

That isn't a problem, because as you admit 10 years is too short a timescale. If temp had gone up year on year over the last 20 years until 1998 you'd have a point. But it hasn't. You cannot assume a trend taken over any 10 year timescale of global temperature (or any data) provides a statistically meaningful test of the background warming trend. There is evidence in the past record that 10 years is too short a timescale:

http://www.skepticalscience.com/Global-war...ed-in-1981.html

That is what is telling us so far

There has been NO significant volcanic eruption in the same last 10 years.To promote cooling.The sun has been ruled out by AGW believers. It is stupidly wrong.But not surprising.

There is simply no significant 11-year cycle visible in the global temperature records, which means the cooling due to a solar cycle minimum and warming due to a solar maximum is slight.

How come a strong La-Ninya produce the single biggest one year drop in world temperature in 100 + years.Somehow brushing aside the awsome CO2 warm forcing power so quickly and for about a year?

Pure chance. If Jan 2007 wasn't so anomolously warm this one year drop (jan 2007 - jan 2008) wouldn't have been the biggest. An argument of massive cooling in 12 months cannot be hinged on whether the first month is anomolously warm or not, that would make no sense.

But before the strong La-ninya came around a year ago.The temperature trend from 1998 to 2007 was still about zero.1998 still remains the high point in last 10 years.

Because 1998 was a strong el nino year and was inflated for that reason, just as temp is being deflated by the current la nina now. For that reason a trend started in 1998, or indeed ending in 2008, is telling us more about enso than any background trend of global temperature (which is what global warming is all about).

This is illustrated by the fact that if you start the same trend in 1996 or 2000 rather than 1998 you get a warming trend.

When the trend direction can alter just by taking the trend 2 years earlier or later that just shows you cannot assign meaning to a trend as small as 10 years fullstop.

It begs the question.What is preventing the trace gas from warming up the planet.In the last 9+ years?

What causes 5 heads in a row sometimes in a coin toss? Chance. A long enough long term trend of ~0.2C a decade with enough noise will occasionally contain such periods of flatness by chance. Again refer to

http://www.skepticalscience.com/Global-war...ed-in-1981.html

Edited April 8, 2008 by shoggoth

[Riverwind]

That isn't a problem, because as you admit 10 years is too short a timescale. If temp had gone up year on year over the last 20 years until 1998 you'd have a point. But it hasn't. You cannot assume a trend taken over any 10 year timescale of global temperature (or any data) provides a statistically meaningful test of the background warming trend. There is evidence in the past record that 10 years is too short a timescale:

WRONG. Learn some statistics. I gave a good link in my previous post.

If someone predicted a 10 degC/decade change then it would be possible to prove the wrong if the temps *only* rose 0.1 deg in 1 year.

If someone predicted a 0.1 degC/decade change the it would be possible to prove them wrong if the temps had a 0.5 deg/decade cooling trend over 10 years.

The IPCC predicted a 0.2 degC/decade increase in temperatures but the actual temperatures have declined slightly over 8 years. This is enough to show statistically that the IPCC predictions are 95% likely to be wrong. Get over it. The person who did the math believes in AGW and believes that warming will start again soon but at a rate much less than what the IPPC predicted. The fact that warmers are so desperate to deny this fact demonstrates why they cannot be trusted to look at the science objectively.

BTW - using the past cooling trends to claim that the current trend is not statistically meaningful is a bogus argument because the IPCC never predicted a 2 degC/century trend in the past. The prediction of 2 degC/century started in 2001 which means the test but start with that date.

Edited April 8, 2008 by Riverwind

[shoggoth]

WRONG. Learn some statistics. I gave a good link in my previous post.

If someone predicted a 10 degC/decade change then it would be possible to prove the wrong if the temps *only* rose 0.1 deg in 1 year.

You tell me to learn some statistics and then post something totally statistically wrong.

A 10C rise in 10 years with the first year rising 0.1C:

0.1C, 2C, 3C, 4C, 5C, 6C, 7C, 8C, 9C, 10C

Compaible with a trend of 10C/decade despite the first year being a 0.1C rise.

The IPCC predicted a 0.2 degC/decade increase in temperatures but the actual temperatures have declined slightly over 8 years. This is enough to show statistically that the IPCC predictions are 95% likely to be wrong. Get over it.

A prediction of 0.2C/decade does not necessarily predict the rise of any *specific* decade, only the average over a suitible time period. One decade could be 0.15C rise while another is 0.25C. The overall period would be 0.2C/decade.

We know the rise in temp over the last 30 years is about 0.2C/decade not because we base that on some arbitary 10 year period (1981-1991 certainly wouldn't give you 0.2C for example), but because 0.2C/decade is about the average for the last 30 years.

BTW - using the past cooling trends to claim that the current trend is not statistically meaningful is a bogus argument because the IPCC never predicted a 2 degC/century trend in the past. The prediction of 2 degC/century started in 2001 which means the test but start with that date.

If you are assuming 2C/century means temps must rise 0.2C between 2001 and 2011 then that is very wrong indeed.

[Riverwind]

Compaible with a trend of 10C/decade despite the first year being a 0.1C rise

I did not state it in my example but any prediction must include an uncertainty interval (this should have been obvious). An uncertainty interval comparible to the IPCC predictions for the 10 degC/decade prediction would be 10 degC +/- 1.5 degC. In other words, a 1 year trend of 0.1 degC would be way outside the uncertainty intervals for the prediction.

More importantly a statistical analysis can never absolutely prove that a prediction is wrong. The best one can say is the prediction is 95% or 99% likely to be false. This means that you could always come up with a sequence of numbers that would be consistent with the prediction no matter what the short term variations occur. However, dreaming up some numbers that might occur does not mean they are LIKELY to occur. IOW, if the temps only rose 0.1 degC after if someone predicted 10 degC/decade +/- 1.5 degG then one can conclude that the 10 degC/decade prediction is MOST LIKELY wrong given 1 year of data.

Similarily, we can conclude that IPCC prediction of 0.2 degC/decade most likely wrong given the slight cooling trend we have seen to date.

We know the rise in temp over the last 30 years is about 0.2C/decade not because we base that on some arbitary 10 year period (1981-1991 certainly wouldn't give you 0.2C for example), but because 0.2C/decade is about the average for the last 30 years.

First, the average over the last 30 years is not 0.2C/decade. It is less than < 0.15 degC/decade depending on the dataset you use. Second, it does not make a difference what happened in the past since the prediction was made starting in 2001. Therefore, the only relevant data is data that was collected AFTER the prediction was made.

If you are assuming 2C/century means temps must rise 0.2C between 2001 and 2011 then that is very wrong indeed.

0.2 degC/decade is the short term prediction made by the IPCC. The long term temperature prediction is more than 0.2 degC/decade. If the IPCC models were right there should have been some observable warming between 2001 and today.

I should point out that it is quite possible (even likely) that warming resume in the near future, however, there is no reason to believe that it will resume at the rates predicted by the IPCC (although it could happen). This statistical analysis simply tells us that it is too early to introduce drastic measures to reduce CO2 and that we should wait until the science figures out why the IPCC predictions were wrong.

Edited April 9, 2008 by Riverwind

[shoggoth]

Well ok lets see what happens, I think it would be fairly easy for the temp rise 2001-2021 to average at about 0.2C/decade without requiring much difference in year to year global temperature than has been observed in the recent past.

[Dog]

I see global warming as the biggest fraud every perpetrated on the public . The sky is falling crowd did not need 10 year or 30 year models to do an about face on global cooling to global warming on the first Earth Day .

As hard as i try to use as much fossil fuel in my V8 pick up my 200 hp 2 stroke powered boat and my snowmobiles i am just a piker compared to Al Gore flying around in his jet . I do encourage all the Eco nuts to conserve as much as you can because i plan on using much much more in the future just like Al .

[eyeball]

Its a great year to be a GW skeptic isn't it?

In the meantime, I wonder if the grounding of American Airline's fleet is providing Dr David Travis with the conditions he needs to further explore global dimming and the possibility that the worst effects of our warming of the Earth's climate has been delayed by contrails.

Some climate scientists have theorized that aircraft contrails (also called vapor trails) are implicated in global dimming, but the constant flow of air traffic previously meant that this could not be tested. The near-total shutdown of civil air traffic during the three days following the September 11, 2001 attacks afforded a rare opportunity in which to observe the climate of the United States absent from the effect of contrails. During this period, an increase in diurnal temperature variation of over 1 °C (1.8 °F) was observed in some parts of the U.S., i.e. aircraft contrails may have been raising nighttime temperatures and/or lowering daytime temperatures by much more than previously thought.

[Riverwind]

In the meantime, I wonder if the grounding of American Airline's fleet is providing Dr David Travis with the conditions he needs to further explore global dimming and the possibility that the worst effects of our warming of the Earth's climate has been delayed by contrails.

Jet contrails would only have a significant effect in the northern hemisphere where the warming has been most pronouced. If these contrails do actuall cause cooling then this would exgarrate the difference between the northern and southern hemisphere - a difference which cannot be explained by CO2 theory. Edited April 12, 2008 by Riverwind