February 29, 2016

Is the world really warming up? Planet may be no hotter at the end of the century than it is now, claims new report using a statistical approach

The Warmists have of course rejected the findings below so perhaps I should note that the difference between the report below and Greenie claims is the difference between fact and theory.  The report below looks at actual temperatures over a long period and finds no overall trend.  Temperatures are plateaued, not rising.

The Greenie approach, on the other hand, is to construct models of what they think influences temperature and use those theoretical models to make predictions.  But for the Greenie approach to give accuratre climate predictions (which they never do) ALL the influences on climate would have to be specified and measured -- which is a practical impossibility.

Whereas the statistical approach below DOES use all the influences -- because it looks at the end-product of all those influences, not just a select few poorly specified influences. So the statistical approach is in principle a much stronger approach to accurate prediction.

But as Bob Ward says below:  "Statistical models are only valid if you assume that the underlying factors are not going to change in the future"

He is right.  He of course believes that the accelerated burning of hydrocarbons in the second half of the C20 is a new factor influencing temperature -- something a statistical approach cannot account for.  So he is right in theory but is he right in fact? IS the accelerated burning of hydrocarbons in the second half of the C20 a new factor influencing temperature?  That is not only completely unproven but is strongly counterindicated by the poor correlation between CO2 levels and temperature.  So Bob  Ward rejects the study below by assuming what he has to prove.

So if we want to rely on evidence for our predictions, the approach below is the only horse in the race.


Global warming is unlikely to take hold before the end of the century according to a controversial new statistical study.

The report, published by the think-tank the Global Warming Policy Foundation, claims that while winters are likely to be slightly warmer, there will be no change in the summer.

Using statistical forecasting methods, the report, written a statistician at Loughborough University, contradicts predictions made by climate scientists.

The Intergovernmental Panel on Climate Change has previously warned the planet was on course to experience warming of between 1°F (0.6°C) and 7.2°F (4°C) by the year 2100 based on climate models.

But Professor Terence Mills claims statistical forecasting methods, which uses data from the past to predict the future by identifying patterns and trends, suggests temperatures will change little.

However, he does warn in his report that the forecasts contain 'rather large measures of imprecision'.

Climate scientists have also described the study as 'silly' and pointed out it failed to take account of basic atmospheric physics.

Professor Mills used statistical models that are more commonly used to forecast economic and financial changes and applied them to three climate data sets.

These included records of global surface temperatures, the global lower troposphere temperatures and the Central England Temperature series, which dates back to 1660.

Writing in his paper, Professor Mills argues that climate scientists may have made errors in their predictions by focusing on recent uplifts in global temperatures.

He said such an approach can be 'highly misleading'. 'There is simply no substitute for analysing the entire temperature record using a variety of well-specified models,' he wrote.

Professor Mills work was seized upon by climate change sceptics as evidence that the predictions being made by climate models are exaggerating the risk posed by global warming.

His paper argues that statistical forecasting methods using in predicting complex financial markets and global economies could be put to good use in understanding the relationships between temperatures and factors that cause them to change.

'In terms of the series analysed throughout the paper, a clear finding presents itself for the two global temperature series,' he said.

'Irrespective of the model fitted, forecasts do not contain any trend, with long-horizon forecasts being flat, albeit with rather large measures of imprecision even from models in which uncertainty is bounded.

'The regional CET series does contain a modest warming signal, the extent of which has been shown to be dependent on the season: winters have tended to become warmer, spring and autumn less so, and summers have shown hardly any trend increase at all.

'The monthly pattern of temperatures through the year has remained stable throughout the entire 355 years of the CET record.'

A statement released by the Global Warming Policy Forum, which was founded by former British chancellor Lord Lawson, welcomed the report.

It said: 'His conclusion that statistical forecasting methods do not corroborate the upward trends seen in climate model projections is highly important and needs to be taken into consideration.

'The topic has direct bearing on policy issues since it provides an independent check on the climate-model projections that underpin calculations of the long-term social costs of greenhouse gas emissions.'

However, there was a mixed response from others who had read the report.

David Stern, an environmental economist at the Crawford School of Public Policy at the Australian National University, described the study as 'silly'.

He said: 'This is a prime case of "mathiness" I think - lots of math that will look sophisticated to many people used to build a model on silly assumptions with equally silly conclusions.'

Dr Richard Betts, head of climate impacts at the Met Office described the paper as 'daft' and that current temperatures were already outside the range predicted in the study.

He reacted to reports of the paper by posting updated graphs from the paper showing the current changes in temperatures on Twitter.

Bob Ward, policy and communications director at the Grantham Research Institute on Climate Change and the Environment at the London School of Economics, told Desmog UK: It's an interesting academic exercise with very little value to policy makers.

'Statistical models are only valid if you assume that the underlying factors are not going to change in the future.

'If the underlying factors are changing, then your statistical model just simply doesn't work, and that's widely recognised.

'We know greenhouse gas concentrations are going up and that's a fundamental for temperature and that's why statistical models have very little skill in predicting the future, they're not able to take account of the fundamental physics.'

SOURCE





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