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Global Warming The Outlook for 2013

Obama’s appointment of Kerry to succeed Hilary Clinton as Secretary of State raises concern that the US may become more favourably inclined to further attempts to secure international agreement on action to reduce emissions (Kerry is on record as being an over-the-top alarmist). This would be tempting in the US context where much of the media still wrongly accepts the claim of a scientific consensus (in Australia the leading exponent is “our” ABC). Also, US polling still shows that global warming is quite widely accepted as a “serious threat” (depending on the poll in the US, it is 45-60 per cent with around 40 per cent thinking it’s due to human activity).

Hopefully, however, the failure of the Doha conference, the continued absence of any upward trend in temperatures, and the continued publication of substantive questioning analyses of the so-called consensus will build on the growing recognition of the sceptical view both in the US and here. It should not be overlooked that the existence of a sceptical view is now publicly recognised whereas it wasn’t a couple of years ago. There is also increasing recognition of the difficulty of securing a meaningful international agreement to action to reduce emissions, most of which now originate in developing countries with lower incomes. The exaggerated claims made by the European Union and the present Australian government are probably helping the sceptic view.

Even so, for sceptics there is a lot of hard yakka ahead in Australia. Although the Opposition says it will, if elected, abandon the pricing of emissions, it still supports action to reduce them through resort to alternative energy sources when it could adopt a policy of wait and see until there is greater certainty about the science ( I have written before suggesting this option). Serious problems also exist in regard to the very extensive regulations at both federal and state levels purporting to be essential to “protect” the environment and where their interpretation seems to be based by courts on acceptance of the (alleged) scientific consensus with little or no regard to alternative views. (This challenging situation is examined in a paper presented at the last Samuel Griffith Society conference by barrister Josephine Kelly on The Constitutionality of the Environmental Conservation Act.) A similar situation exists in the US where legal challenges to the Environment Protection Agency’s decision that greenhouse gases endanger human health and welfare have been rejected by courts essentially because “the science” as interpreted by “the authorities” (ie the EPA!) is not legally challengeable.

Leak of IPCC Draft

The recent leaking of the IPCC draft on the physical science has produced many comments on comparisons with past reports and on changes in conclusions since the last IPCC epistle in 2007. Of particular interest is the comparison of temperature predictions made in the latest weekly report by the US Science and Environmental Policy Project (an important source of critiques of IPCC type assessments). This report notes the following failure of predictions (or projections) of temperature for 2012 by the models used in successive IPCC publications, viz first (in 1990) +0.5 degree, second +0.3 deg, third +0.39 deg, fourth +0.37 deg, actual +0.12-0.16 deg. It also notes that predicted concentrations of methane were “far above the measured concentrations”.

The SEPP report adds that, while the general press continues to largely ignore these failures, “a greater proportion of the general public is being made aware that there is no consensus”. It also draws attention to the “great uncertainty” in the modelling used by the IPCC to suggest that aerosols have a strong cooling effect (and hence have temporarily limited the increase in temperatures from CO2). Qualified sceptics amongst Australian climate scientists also question whether the modelling in regard to both temperature predictions and aerosols has any substantive credibility.

Various aspects of what IPCC reports rely are also discussed below in an article by Matt Ridley, a British scientist with considerable expertise in climate science. That this was published in The Australian on 20 December (after being published on 18 December in the Wall St Journal) is another sign of recognition of the sceptical view.

Climate Change Authority

The CCA, which was established in July 2012 as purportedly an independent body, advises the government on a range of issues regarding policies to reduce emissions, including carbon pricing and renewable energy targets. The head of the authority, Bernie Fraser, is a former head of Treasury and the Reserve Bank and was quoted in the AFR on 20 December as saying he has great respect for “the science”, cannot understand the disdain some take to it, but at the same time doesn’t understand it.

It is a pity Fraser has not commissioned advice on the claims made by those scientists who believe in the dangerous warming thesis, two of whom are members of his board of eight. (the authority has the power to do that without consulting the Minister for Climate Change). His economics training would quickly have shown that analyses by many non-alarmist climate scientists suggest it is very unlikely that increasing emissions will cause temperatures to increase to anywhere near the extent predicted by the alarmists.

In his interview with the AFR Fraser seemingly accepted that carbon pricing is a better way of reducing emissions than resorting to mandatory renewable energy targets. But in its detailed report on MRETs, published on 19 December, the Authority simply took the view that “the scheme is progressing towards its objectives of encouraging additional generation of electricity from renewable sources and reducing greenhouse gas emissions in the electricity sector.” This objective would involve obtaining upwards of 20 per cent of energy from renewable sources, such as wind and solar, considerably more costly than coal or gas.

Recent Research Questioning the Science

Recent analysis by physicist, Dr Tom Quirk, shows that atmospheric CO2 concentrations and sea surface temperatures actually fell slightly in the mid 1940s in the tropics and southern hemisphere even though usage of fossil fuels was growing. This analysis shows that the temperature fall occurred in all three of the Atlantic, Indian and Pacific Oceans. Needless to say it is a most unusual event for a fall to occur. The fall is also seen at that time in land based temperatures in SE Australia which faces the Pacific Ocean.

In an earlier (peer reviewed) analysis, Quirk showed that in the mid 1970s and the mid 1990s changes in ocean surface temperatures occurred due to the Pacific and then the Atlantic Decadal Oscillations. These corresponded with changes in measured atmospheric CO2. Major increases in land based global temperatures also followed these changes.

These oscillations are natural occurrences marked by events such as the Great Pacific Climate Shift where in 1976-78 the ocean surface temperatures in the North Pacific Ocean started to increase. This change was finally identified as part of the Pacific Decadal Oscillation with cool and warm phases and with each phase having a period of some twenty to thirty years. These changes are reflected in global temperatures.

In the mid 1940s a Pacific Decadal Oscillation also occurred but it would be limited to the northern Pacific Ocean and hence does not explain the temperature fall in the southern hemisphere and in all oceans.

These two examples are contrary to the thesis that temperature increases are caused by human activity and add to existing doubts about the present state of understanding of how ultimately global temperatures are determined. The possibility of a connection between sea surface temperatures and atmospheric CO2 concentrations cannot be ruled out: for example, to what extent is CO2 absorbed by the oceans. This clearly warrants further extensive research before action to reduce emissions is justifiable.

IPCC must accept temperature rises are small and benign

Matt Ridley, The Wall Street Journal, December 20, 2012

FORGET the Doha climate jamboree that ended this month. The theological discussions in Qatar of the arcana of climate treaties are irrelevant. By far the most important debate about climate change is taking place among scientists, on the issue of climate sensitivity: how much warming will a doubling of atmospheric carbon dioxide actually produce? The Intergovernmental Panel on Climate Change has to pronounce its answer to this question in its Fifth Assessment Report next year.

The general public is not privy to the IPCC debate. But I have been speaking to somebody who understands the issues: Nic Lewis. A semi-retired successful financier from Bath, England, with a strong mathematics and physics background, Lewis has made significant contributions to the subject of climate change.

He first collaborated with others to expose major statistical errors in a 2009 study of Antarctic temperatures. Last year he found that the IPCC had, by an unjustified statistical manipulation, altered the results of a key 2006 paper by Piers Forster of Reading University and Jonathan Gregory of the Met Office (Britain's weather service), to vastly increase the small risk that the paper showed of climate sensitivity being high. Lewis found the IPCC had misreported the results of another study, leading to the IPCC issuing an erratum last year.

Lewis tells me that the latest observational estimates of the effect of aerosols (such as sulfurous particles from coal smoke) find they have much less cooling effect than thought when the last IPCC report was written. The rate at which the ocean is absorbing greenhouse-gas-induced warming is also now known to be fairly modest. In other words, the two excuses used to explain away the slow, mild warming we have actually experienced - culminating in a standstill in which global temperatures are no higher than they were 16 years ago - no longer work.

In short: we can now estimate, based on observations, how sensitive the temperature is to carbon dioxide. We do not need to rely heavily on unproven models. Comparing the trend in global temperature over the past 100-150 years with the change in "radiative forcing" (heating or cooling power) from carbon dioxide, aerosols and other sources, minus ocean heat uptake, can now give a good estimate of climate sensitivity.

The conclusion - taking the best observational estimates of the change in decadal-average global temperature between 1871-80 and 2002-11, and of the corresponding changes in forcing and ocean heat uptake - is this: a doubling of CO2 will lead to a warming of 1.6-1.7C.

This is much lower than the IPCC's current best estimate, 3C.

Lewis is an expert reviewer of the recently leaked draft of the IPCC's WG1 Scientific Report. The IPCC forbids him to quote from it, but he is privy to all the observational best estimates and uncertainty ranges the draft report gives. What he has told me is dynamite.

Given what we know now, there is almost no way the feared large temperature rise is going to happen. Lewis comments: "Taking the IPCC scenario that assumes a doubling of CO2, plus the equivalent of another 30 per cent rise from other greenhouse gases by 2100, we are likely to experience a further rise of no more than 1C."

A cumulative change of less than 2C by the end of this century will do no net harm. It will actually do net good - that much the IPCC scientists have already agreed upon in the last IPCC report. Rainfall will increase slightly; growing seasons will lengthen; Greenland's ice cap will melt only very slowly, and so on.

Some of the best recent observationally based research also points to climate sensitivity being about 1.6C for a doubling of CO2. An impressive study published this year by Magne Aldrin of the Norwegian Computing Centre and colleagues gives a most-likely estimate of 1.6C. Michael Ring and Michael Schlesinger of the University of Illinois, using the most trustworthy temperature record, also estimate 1.6C.

The big question is this: will the lead authors of the relevant chapter of the forthcoming IPCC scientific report acknowledge that the best observational evidence no longer supports the IPCC's existing 2-4.5C "likely" range for climate sensitivity? Sadly, this seems unlikely - given the organisation's record of replacing evidence-based policymaking with policy-based evidence-making, as well as the reluctance of academic scientists to accept that what they have been maintaining for many years is wrong.

How can there be such disagreement about climate sensitivity if the greenhouse properties of CO2 are well established? Most people assume that the theory of dangerous global warming is built entirely on carbon dioxide. It is not.

There is little dispute among scientists about how much warming CO2 alone can produce, all other things being equal: about 1.1-1.2C for a doubling from pre-industrial levels. The way warming from CO2 becomes really dangerous is through amplification by positive feedbacks - principally from water vapour and the clouds this vapour produces.

It goes like this: a little warming (from whatever cause) heats the sea, which makes the air more humid - and water vapour itself is a greenhouse gas. The resulting model-simulated changes in clouds generally raise warming further, so the warming is doubled, trebled or more.

That assumption lies at the heart of every model used by the IPCC, but not even the most zealous climate scientist would claim that this trebling is an established fact. For a start, water vapour may not be increasing. A recent paper from Colorado State University concluded that "we can neither prove nor disprove a robust trend in the global water vapour data." And then, as one Nobel Prize-winning physicist with a senior role in combating climate change admitted to me the other day: "We don't even know the sign" of water vapour's effect - in other words, whether it speeds up or slows down a warming of the atmosphere.

Climate models are known to poorly simulate clouds, and given clouds' very strong effect on the climate system - some types cooling the Earth either by shading it or by transporting heat up and cold down in thunderstorms, and others warming the Earth by blocking outgoing radiation - it remains highly plausible that there is no net positive feedback from water vapour.

If this is indeed the case, then we would have seen about 0.6C of warming so far, and our observational data would be pointing at about 1.2C of warming for the end of the century. And this is, to repeat, roughly where we are.

The scientists at the IPCC next year have to choose whether they will admit - contrary to what complex, unverifiable computer models indicate - that the observational evidence now points towards lukewarm temperature change with no net harm. On behalf of all those poor people whose lives are being ruined by high food and energy prices caused by the diversion of corn to biofuel and the subsidising of renewable energy driven by carboncrats and their crony-capitalist friends, one can only hope the scientists will do so.

Matt Ridley (Matthew White, 5th Viscount Ridley), FRSL, FMedSci, DL (born 7 February 1958), is a British scientist, journalist and author. He writes the Mind and Matter column in The Wall Street Journal and has written on climate issues for various publications for 25 years. His family leases land for coalmining in northern England, on a project that will cease in five years.

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