The Climate Change debate in 2010

So what is the New Year going to bring in the way of the Climate Change debate? I went over to RealClimate where they are acclaiming the accuracy of climate predictions, despite showing a graph which falsifies them. The graph is claimed to show how well Dr. Hansen’s predictions from 1988 have held up. (I have removed the trend lines from the graph below which otherwise comes from their site). It actually does the opposite.

The RealClimate plot showing the data reported as being the actual temperatures (in color) as opposed to the values predicted by Dr Hansen, which are shown in shades of grey and black.

In Dr. Hansen’s paper he gives the conditions for the 3 curves as:

Scenario A assumes continued exponential trace gas growth, scenario B assumes a reduced linear linear growth of trace gases, and scenario C assumes a rapid curtailment of trace gas emissions such that the net climate forcing ceases to increase after the year 2000.

As the media keep telling us we have continued to see the carbon dioxide levels rise at the rate predicted to yield curve A; yet the actual temperatures as reported by the folks above, is falling below line C, that which Dr. Hansen stated would require a rapid curtailment of GHG. Didn't happen! The predictions are therefore wrong.

There are two points that will likely come up in the next year as the discussion continues. Firstly – while RealClimate tries to tie the reported temperature changes to prediction B and thus to a continued and ultimately dramatic rise in global temperature, there are those who argue that there may be a period of “stabilization” or a “pause” before the temperature begins to rise again. The problem with that argument is that if you accept the extreme state, as Sharon Begley did in the Kindle edition of Newsweek for Jan 4th (but not yet in the electronic version – hence the longer ref), then there should be no “pause.” In the original paper Dr. Hansen claimed that there were no natural forces they could include that would explain the rise in global temperature and that it could only be explained by the GHG. Yet now we have natural forces that folk are rushing to use to explain the lack of acceleration in global temperatures. You can’t have it both ways, for if natural forces can explain the temperature changes that stop the runaway global warming that Dr Hansen et al were predicting, then they are of sufficient magnitude that they could have been responsible for the rising temperatures that we have seen so far. (Since they are causing the difference between the colored and grey lines which are now reaching levels equal to the actual temperature rise that has been seen).

To distract folks from noticing this, I expect that we will continue to see exaggerated claims for the impact of GHG in the columns of those reporters and editors who (at least nominally) are supposed to look at both sides of an issue. The degree with which they are willing to distort the data is something I have commented on before (relative to Bangladesh and Egypt for example), but which is again illustrated by Ms. Begley. In a recent piece on the impact that dams have on local weather and rainfall, she continues her diatribe against those who question GHG impact and illustrates her point using a paper recently in EOS. That paper shows that the changes in land use and land cover brought about by the presence of a large dam, and the lake it generates, can alter regional climate by, for example, increasing rainfall. Papers are quoted in that article that argue that it can lead to heavier rainfalls and changes in rainfall patterns, enhancing thunderstorms. (Part of it comes from the lake and part from the increased activity, whether farming or a larger urban environment supported by the dam).

Effect of dam on local precipitation (after Eltahir E.A. B. and Bras R.L. (1996) “Precipitation recycling”, Rev. Geophys., 34(3), 367–378.)

This has actually almost nothing to do with global warming – but that does not stop those who wish to blame the woes of the world on GHG from co-opting it. And the concerns that they bring include that heavier rains will threaten the stability of the dams. (Side note – since I have taught classes that include dam stability I must confess to not quite following why they feel that is the case, since properly designed dams should be able to cope quite easily, since it is what they are designed for – and the additional rain might even help with hydro-electric power generation, which is a concern in areas where drier spells (such as in India this year) otherwise are a problem.

Well that was a bit more of a digression than I had intended, but it illustrates the first point I wanted to make, that science be damned those who are selling the disasters to be caused by global warming are not going to be dissuaded by the odd actual fact, but will instead continue to exaggerate and tie in events that may not, in fact be related.

The second forthcoming event may have some impact on this, with the inquiries that are being carried out into the goings on in the CRU in England, and with Dr. Mann at Penn State. The ramifications of these are potentially quite significant, since, as the graph at the top shows, the CRU interpretation of the measured temperatures lies very close to that reported by GISS. Now there are some questions as to the accuracy with which the CRU data was interpreted, and those codes are now being scrutinized as the global data becomes more openly available. One can presume, potentially that this year will produce a more open, and therefore more willingly accepted register of actual global temperature changes. What will be interesting to see is whether this will also keep the values close to those reported by GISS. The investigations by E.M. Smith suggest that questions could be raised about the way in which the global temperature is being assessed by that office, and the withdrawal of this process from immediate public scrutiny may or may not be allowed to stand, but will continue to raise questions as to the honesty of the resulting product.

In short there is going to be lots to debate about in the coming year, and though I suspect that each of the two camps will continue to talk past the other, and to their own set of believers, there may be enough real knowledge that falls out of the slowly opening process, that we may be more convinced of what is truly going on.