Posts Tagged ‘computer models’

How climate science models are validated

August 20, 2014

Mathematical and computer models are wonderful tools. Once they can be validated they are powerful methods of interpolation. They are useful methods of improving the understanding embodied in the models by extrapolation. The divergence between extrapolated model results and real data can then be used for improving the models to better account for real data. If model results do not fit real data it is time to change the model.

Extrapolated model results are never evidence. They are just indicators of what may come to pass provided that the model – in spite of all its simplifications – does truly apply.

And when climate model results are fudged to move towards climate data which, in turn, has to be fudged to move towards the model results, one wonders whether there is any scientific method left in “climate science”.

This is reported by WUWT from a recent paper from ETH Zurich.

If the model data is corrected downwards, as suggested by the ETH researchers, and

the measurement data is corrected upwards, as suggested by the British and Canadian researchers,

then the model and actual observations are very similar.

Shameless is one adjective that comes to mind.

Fraudulent is another.



New computer simulations to find new excuses for recent lack of global warming

September 19, 2011

The lack of any global warming over the last decade while carbon dioxide emissions have been increasing is extremely worrying to the global warming orthodoxy. Recently “peer-reviewed” papers have attempted to find excuses for this lack of warming. Sulphur emissions from coal plants in China it has been suggested have been cooling the earth! The effects of soot in the atmosphere have also been blamed for reality and measurements not corresponding to the (sometimes fanciful) results of climate models. Needless to say it would not be politically correct to accept that solar influences – through clouds for example – may be so powerful as to make any anthropogenic effects quite insignificant with regard to climate.

One school of global warming believers believe that the missing heat is being hidden like some Loch Ness monster in the deep oceans and will come back to haunt us in due course. Of course measurements can not find this “hidden” deep ocean heat. It is far too well hidden for that. But the “unhidden” measurable ocean heat content (upto a depth of 700m) also confirm the flattening out of global warming.

As Bob Tisdale had pointed out in WUWT: Global Ocean Heat Content Is Still Flat

Figure 1 is a time-series graph of the NODC Global Ocean Heat Content Anomalies from the start of the dataset (1st Quarter of 1955) to present (2nd Quarter of 2011).

Figure 1: Global Heat content

And as many are aware, Climate Model Projections of Ocean Heat Content anomalies did not anticipate this flattening. Figure 2 compares the ARGO-era (2003 to present) NODC Global Ocean Heat Content anomalies to the GISS Model-E Projection of 0.7*10^22 Joules per year. The linear trend of the observations is approximately 7% of the trend projected by the model mean of the GISS Model-E.

Figure 2 - Ocean heat content:measurements compared to models

But the heat cannot hide from the speculative computer models of our intrepid global warmers. And since they cannot find this heat they have instead programmed a super-computer to tell us that it exists and will appear again in a decade or two. A new paper entitled Deep oceans can mask global warming for decade-long periods is to be published online on September 18 in Nature Climate Change. The title itself illustrates the defense. The  National Center for Atmospheric Research/University Corporation for Atmospheric Research has issued a press release which states:

Yet emissions of greenhouse gases continued to climb during the 2000s, and satellite measurements showed that the discrepancy between incoming sunshine and outgoing radiation from Earth actually increased. This implied that heat was building up somewhere on Earth, according to a 2010 study published in Science by NCAR researchers Kevin Trenberth and John Fasullo. 

The two scientists, who are coauthors on the new study, suggested that the oceans might be storing some of the heat that would otherwise go toward other processes, such as warming the atmosphere or land, or melting more ice and snow. Observations from a global network of buoys showed some warming in the upper ocean, but not enough to account for the global build-up of heat.

And when there are no measurements to back up some speculation a new computer model is deployed:

The study, based on computer simulations of global climate, points to ocean layers deeper than 1,000 feet (300 meters) as the main location of the “missing heat” during periods such as the past decade when global air temperatures showed little trend. The findings also suggest that several more intervals like this can be expected over the next century, even as the trend toward overall warming continues.

“We will see global warming go through hiatus periods in the future,” says NCAR’s Gerald Meehl, lead author of the study. “However, these periods would likely last only about a decade or so, and warming would then resume. This study illustrates one reason why global temperatures do not simply rise in a straight line.”

The simulations, which were based on projections of future greenhouse gas emissions from human activities, indicated that temperatures would rise by several degrees during this century. But each simulation also showed periods in which temperatures would stabilize for about a decade before climbing again. For example, one simulation showed the global average rising by about 2.5 degrees Fahrenheit (1.4 degrees Celsius) between 2000 and 2100, but with two decade-long hiatus periods during the century.

During these hiatus periods, simulations showed that extra energy entered the oceans, with deeper layers absorbing a disproportionate amount of heat due to changes in oceanic circulation. The vast area of ocean below about 1,000 feet (300 meters) warmed by 18% to 19% more during hiatus periods than at other times. In contrast, the shallower global ocean above 1,000 feet warmed by 60% less than during non-hiatus periods in the simulation.

“This study suggests the missing energy has indeed been buried in the ocean,” Trenberth says. “The heat has not disappeared, and so it cannot be ignored. It must have consequences.”

This is plain speculation. And it looks to me that these simulations are only done for the sake of rescuing previous computer models which are beginning to be shining examples of GIGO. Even super-computers can only produce rubbish when the models are developed by zealots. And as Bob Tisdale comments:

An explanation for why Global Ocean Heat Content Is Still Flat. … I’d like to see some supporting observations, otherwise this is just speculation for something that Trenberth is doggedly trying to explain away. My question is; show me why some years the deep ocean doesn’t mask global warming. It’s not like that big heat sink was suddenly removed.

Computer models are only models – and subject to common sense

May 25, 2011

Once again the blind belief in computer models has closed down parts of European air space. Observations and measurements are given less weight than computer models which are at best crude approximations of a chaotic system. The unthinking belief in approximations to reality merely because they are generated by computer models denies the sapience in homo sapiens!!


Most flights have resumed across the UK after a day that saw thousands of passengers affected by an ash cloud from the erupting Icelandic volcano. Air traffic control company Nats said harmful concentrations of ash dispersed from UK airspace overnight. But some flights within the UK and a number to Germany will be cancelled.

As one blogger puts it:

Airline managers are complaining that last year, officials did not do enough to check the actual conditions in the air, instead relying too heavily on computer models showing where the ash was supposed to be. Yet, despite the experience, the International Air Transport Association (IATA) is saying that it is “astonishing and unacceptable” that a British aircraft that is supposed to check actual conditions has been unable to fly.

The disruption arises in part from “volatile winds” which are said to be carrying clouds of volcanic ash down from Iceland over the northern British Isles. But those same winds which caused the rough weather yesterday must also have dispersed the ash.

Without real data, however, forecasters are unable to provide accurate information on ash density and particle size, relying instead on weather patterns and computer modelling to give a rough approximation of conditions. And, with no clear guidance as to closure rules, the only significant difference between this year and last is that the weather conditions are more changeable, allowing more favourable estimates of ash dispersion to be made.

Climate Realists: We know that the Met Office doesn’t bother much with evidence, witness Prof John Mitchell’s unguarded remarks at the Downing College Conference:

People underestimate the power of models. Observational evidence is not very useful,… Our approach is not entirely empirical.

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