Some GW denier said the temperatures have been declining in the past 10 years...?

Question

How did he reach this conclusion?

I'm looking at the NASA plots and they show the opposite. Temperatures are increasing.

http://data.giss.nasa.gov/gistemp/2007/

"We can see from NASA's own data that this is not occurring, as the temperatures have been steady to declining over the last 10 years."

- GW denier

http://answers.yahoo.com/question/index;_ylt=AjULY13Qxg1.IUYkBURRrnzpy6IX;_ylv=3?qid=20080324101815AAMLQ8Y

Answer 1

its right here:

Last Monday - on ABC Radio National, of all places - there was a tipping point of a different kind in the debate on climate change. It was a remarkable interview involving the co-host of Counterpoint, Michael Duffy and Jennifer Marohasy, a biologist and senior fellow of Melbourne-based think tank the Institute of Public Affairs. Anyone in public life who takes a position on the greenhouse gas hypothesis will ignore it at their peril.

Duffy asked Marohasy: "Is the Earth stillwarming?"

She replied: "No, actually, there has been cooling, if you take 1998 as your point of reference. If you take 2002 as your point of reference, then temperatures have plateaued. This is certainly not what you'd expect if carbon dioxide is driving temperature because carbon dioxide levels have been increasing but temperatures have actually been coming down over the last 10 years."

Duffy: "Is this a matter of any controversy?"

Marohasy: "Actually, no. The head of the IPCC (Intergovernmental Panel on Climate Change) has actually acknowledged it. He talks about the apparent plateau in temperatures so far this century. So he recognises that in this century, over the past eight years, temperatures have plateaued ... This is not what you'd expect, as I said, because if carbon dioxide is driving temperature then you'd expect that, given carbon dioxide levels have been continuing to increase, temperatures should be going up ... So (it's) very unexpected, not something that's being discussed. It should be being discussed, though, because it's very significant."

Answer 2

here's my favourite graph;

http://www.realclimate.org/index.php/arc...

good article too.

Answer 3

I'd like to get his results from surveys and show him his faults as we have been in a drought for at least nine of those ten years that he has been talking about due to hot weather.  also we are ever so slowly creping closer to more 40degree celsius days here.

Answer 4

Basically what they do is cherrypick the hottest previous year (1998 due to an anomalously strong El Nino cycle that year), and then draw a line between 1998 and Present.  Because 1998 is the hottest year on record - voila, it's cooling!

Of course, this is not a valid statistical test.  If you apply a best fit line, the slope continues upward, even if you still cherrypick 1998 as your starting year:

http://tamino.files.wordpress.com/2007/0...

And as you saw in the NASA GISS data, if you apply a 5-year running mean, it also continues upward:

http://data.giss.nasa.gov/gistemp/graphs...

So to claim that temperatures have been steady or declining is simply a case of intentional deceit or statistical ignorance.

The first answerer quoted a biologist from a conservative think-tank.

http://en.wikipedia.org/wiki/Institute_o...

That's a curious place to get your climate science information.  Another example of cherrypicking.

*edit* the data linked by Jello is average monthly temperature anomaly - difference from the 1951-1980 mean (14°C).  Of course you really can't tell anything by just looking at monthly data over the past 10 years.  That's why scientists apply statistical tests which show that the warming trend continues.

Answer 5

We can look at NASA's own data to see that there hasn't been any warming over the last 10 years.

http://data.giss.nasa.gov/gistemp/graphs...

If anything, this NASA graph shows temperatures declining!