http://www.realclimate.org/index.php/archives/2008/12/2008-temperature-summaries-and-spin/

You can get slightly different pictures if you pick the start year differently, and so this isn’t something profound. Picking any single year as a starting point is somewhat subjective and causes the visual aspect to vary looking at the trends is more robust. However, this figure does show that in models, as in data, some years will be above trend, and some will be below trend. Anyone who expresses shock at this is either naive or well, you know.

And as for dismissing and entire data set just because it was measured on the ground…WTF?

I’ll let you get back to Never Never Land now as it’s obvious by the way you discount data (you know, all that data that existed before 2001) that goes against your preconceived notions that you will never accept the truth.

So what. Visually the correlation between the surface temperature record and the satellite record is very high, so while there is a small offset between the two, both records show the same underlying trend.

I’ll repeat this link in case you didn’t read it last time.

Open Mind

Pay attention, Bob Carter: THIS IS WHAT GLOBAL WARMING IS ABOUT. IT’S NOT ABOUT LESS-THAN-A-DECADE NATURAL FLUCTUATION, IT’S ABOUT THE INEXORABLE INCREASE FROM DECADE TO DECADE.

If you are sincere in your argument, get back to us when and ONLY when you have understood the data and conclusions in Tamino’s post.

In respect of Howat’s later publications of his work in Greenland – answering bob d’s cajoling reference to Howat’s output in science 2007 – I made an extensive comment last evening which did not appear here.

Was it blocked or dispensed/disposed I don;t know for sure, but do see that the commenter mentioned almost continually commented over the period of my activity.

Hence a wait – yes, the information for standard readers was important enough to take this trouble – before testing with this post..

If it gets through then maybe in the ‘lull’ of early morning a retry will make it..

Can’t seem to find that global cooling you keep telling us been happening over the last few years either.

It’s here.
The graph you linked to ends in 2007, for some reason. If you want a good detailed discussion about global temps and how well TAR and AR4 are doing, I suggest you try Lucia’s Blackboard. She’s neutral (like woodfortrees.org), and generally does good work. She describes herself as a ‘lukewarmer’, in that she believes in AGW, but not necessarily everything the IPCC puts out. I disagree with some of the things she writes, but then I can’t fault her logic on most things, and so far I have seen few who can.
One niggle I have is she often uses GISS or HadCRUT datasets, which are surface-based and useful only for historical purposes when looking at temps and trends prior to the satellite age. I dealt with this a bit in my long rambling post that the dog ate.

Here’s another graph comparing them. Note how the HadCRUT3v data consistently over-reads. Nearly everyone uses UAH for recent graphs, simply because it’s satellite based, reading constantly over the whole globe (except for two small bits over each pole). RSS is similar, also satellite based.

I’m interested in how well the IPCC models have performed since the model runs up to 2001,

And yet you’re still going on about one prediction that the IPCC model made? Out of how many? 10s, 100s, 1000s?

Can’t seem to find that global cooling you keep telling us been happening over the last few years either.

The problem is that the climate doesn’t seem to lend itself well to this kind of modelling. I’m not sure where the problems lie, but I’ve noticed the IPCC doesn’t seem to share this view, and instead makes the following quite strong claims (AR4):

“There is considerable confidence that climate models provide credible quantitative estimates of future climate change, particularly at continental scales and above. This confidence comes from the foundation of the models in accepted physical principles and from their ability to reproduce observed features of current climate and past climate changes. Confidence in model estimates is higher for some climate variables (e.g., temperature) than for others (e.g., precipitation). Over several decades of development, models have consistently provided a robust and unambiguous picture of significant climate warming in response to increasing greenhouse gases.’

‘Considerable confidence’, credible quantitative estimates’, etc.

COLUMBUS, Ohio The recent dramatic melting and breakup of a few huge Greenland glaciers have fueled public concerns over the impact of global climate change, but that isn't the island's biggest problem.

A new study shows that the dozens of much smaller outflow glaciers dotting Greenland's coast together account for three times more loss from the island's ice sheet than the amount coming from their huge relatives.

In a study just published in the journal Geophysical Research Letters, scientists at Ohio State University reported that nearly 75 percent of the loss of Greenland ice can be traced back to small coastal glaciers.

Ian Howat, an assistant professor of earth sciences and researcher with Ohio State's Byrd Polar Research Center, said their discovery came through combining the best from two remote sensing techniques. It provides perhaps the best estimate so far of the loss to Greenland's ice cap, he says.

[GC Martin here: Facts: from Howat's website: "Many retreats began with an increase in thinning rates near the front in the summer of 2003, a year of record high coastal-air and sea-surface temperatures." ]

Aside from Antarctica, Greenland has more ice than anywhere else on earth. The ice cap covers four-fifths of the island’s surface, is 1,491 miles (2,400 kilometers) long and 683 miles (1,100 kilometers) wide, and can reach 1.8 miles (3 kilometers) deep at its thickest point.

As global temperatures rise, coastal glaciers flow more quickly to the sea, with massive chunks breaking off at the margins and forming icebergs. And while some of the largest Greenland glaciers such as the Jakobshavn and Petermann glaciers on the northern coast are being closely monitored, most others are not.

Howat and his colleagues concentrated on the southeastern region of Greenland, an area covering about one-fifth of the island’s 656,373 square miles (1.7 million square kilometers). They found that while two of the largest glaciers in that area Kangerdlugssuaq and Helheim contribute more to the total ice loss than any other single glaciers, the 30 or so smaller glaciers there contributed 72 percent of the total ice lost.

“We were able to see for the first time that there is widespread thinning at the margin of the Greenland ice sheet throughout this region.

“We’re talking about the region that is within 62 miles (100 kilometers) from the ice edge. That whole area is thinning rapidly,’ he said.

[GCM here: Howat says that all of the glaciers are changing within just a few years and that the accelerated loss just spreads up deeper into the ice sheet.]

To reach their conclusions, the researchers turned to two ground-observing satellites. One of them, ICESAT (Ice, Cloud, and land Elevation Satellite), does a good job of gauging the ice over vast expanses which were mostly flat.

On the other hand, ASTER (Advanced Spaceborne Thermal Emission and Reflection Radiometer) does a better job at seeing changes at the steeper, less-flat margins of the ice sheet, Howat said.

“We simply merged those data sets to give us for the first time a picture of ice elevation change the rate at which the ice is either going up or down at a very high (656-foot or 200-meter) resolution.

“They are a perfect match for each other,’ Howat said.

“What we found is the entire strip of ice over the southeast margin, all of these glaciers, accelerated and they are just pulling the entire ice sheet with it,’ he said.

Howat said that their results show that such new findings don’t necessarily require new types of satellites. “These aren’t very advanced techniques or satellites. Our work shows that by combining satellite data in the right way, we can get a much better picture of what’s going on,’ Howat said.

My sole addition to this information is to say that the commenters contraire evident on this thread have been indulging themselves in what is regarded elsewhere as manufactured debate. For more on this I’d recommend Leah Ceccarelli at Washington University.

My postscript might be that Bob D in particular is faced not with a Howat so much as a Howzat! And the finger is straight plumb.

There’s no point in looking back further, the models had the advantage of hindsight before that.

Well no. You are misrepresenting how models work. The ‘advantage’ of hindsight is how they are calibrated. I mean I do this sort of thing for a living; modern process control models collect vast amounts of historic data and utilise it to create a tool that predicts the future of behaviour of the process.

Crucially what the model predicts is not how the dependent output variables are going to behave (reality is too chaotic for that), rather they yield useful information about the relationships between the input and output variables, allowing the engineer to sensibly react to changes in the process.

In essence the ‘tropical hotspot’ is not the so called ‘fingerprint’, rather it is stratospheric cooling that is. And apparently that is what has been occuring.

I’m afraid not. You see, the whole “it’s the stratospheric cooling that matters” thing has only appeared after it became clear there is no hotspot. That’s not science, that’s politics. Have a look again at Fig 9.1 and tell me that a huge, almost 1C anomaly above the tropics shouldn’t be glaringly apparent.

The other problem you have with that approach is you are now contradicting Ben Santer, the man responsible for those models in the IPCC AR4 Fig 9.1.

He says the following:

‘ Our paper compares modeled and observed atmospheric temperature changes in the tropical troposphere. We were interested in this region because of an apparent inconsistency between computer model results and observations.
Since the late 1960s, scientists have performed experiments in which computer models of the climate system are run with human-caused increases in atmospheric concentrations of greenhouse gases (GHGs). These experiments consistently showed that increases in atmospheric concentrations of GHGs should lead to pronounced warming, both at the Earth’s surface and in the troposphere. The models also predicted that in the tropics, the warming of the troposphere should be larger than the warming of the surface. However, most available estimates of tropospheric temperature changes obtained from satellites and weather balloons (radiosondes) implied that the tropical troposphere had actually cooled slightly over the last 20 to 30 years (in sharp contrast to the computer model predictions, which show tropospheric warming).”
-Fact Sheet for “Consistency of Modelled and Observed Temperature Trends in the Tropical Troposphere’, by B.D. Santer et al. International Journal of Climatology Oct 2008

Your second gem is known as ‘cherry picking’ the data, and is a totally dishonest tactic which disqualifies you from any serious discussion. The 8 years of data from 2001 is far too short a period of time to say anything meaningful about an underlying long-term trend.

Hardly. Read carefully. I’m interested in how well the IPCC models have performed since the model runs up to 2001, and I was replying to lprent’s question of what it would take to change my mind. There’s no point in looking back further, the models had the advantage of hindsight before that. Remember that for AR4 they also had the advantage of hindsight over TAR, yet they still predicted a +0.2C/decade warming, in spite of the cooling that had occurred since TAR.