Taking political action at every possible threat falls somewhere in the direction of criminal or stupid (er – OK I guess that is typical of legislators).

There is enough to doubt if C02 is forcing higher temps considering that since 1988, global temps have only increased a fraction of a degree, while C02 has skyrocketed.

Still, there is good reason to proceed with a global clean energy revolution, despite C02. Energy security, independence, and moral economic reasons are enough cause for any skeptic to firmly support a transformation from fossil consumption to cleaner.

What constitutes ‘dangerous’ climate change, in the context of the UN Framework Convention on Climate Change, remains open to debate.

Once we decide what degree of (for example) temperature rise the world can tolerate, we then have to estimate what greenhouse gas concentrations in the atmosphere should be limited to, and how quickly they should be allowed to change.

These are very uncertain because we do not know exactly how the climate system responds to greenhouse gases.

The next stage is to calculate what emissions of greenhouse gases would be allowable, in order to keep below the limit of greenhouse gas concentrations. This is even more uncertain, thanks to our imperfect understanding of the carbon cycle (and chemical cycles) and how this feeds back into the climate system.

In view of the above how can they make specific statements and say that the science is certain?

The answer is they can’t, but to keep their jobs and funding they have to keep the ball in the air. The UK Tyndall Centre had the answer:

The Social Simulation of the Public Perception of Weather Events and their Effect upon the Development of Belief in Anthropogenic Climate Change Dennis Bray and Simon Shackley, September 2004. Tyndall Centre for Climate Change Research.

Global warming (or climate change) is, without elaboration, a much debated and contested issue. Not only is it contested among scientists, but also among all those with vested interests.

We suggest that, in the realm of the public, forces act to maintain or denounce a perceived reality which has already been constructed. That is, an issue introduced by science (or media for that matter) needs continual expression of confirmation if it is to be maintained as an issue.

In this paper, we explore under what conditions belief in global warming or climate change, as identified and defined by experience, science and the media, can be maintained in the public’s perception.

As the science itself is contested, needless to say, so are the potential policy changes. So how then do people make sense or construct a reality of something that they can never experience in its totality (climate) and a reality that has not yet manifest (i.e. climate change)?

To endorse policy change people must ‘believe’ that global warming will become a reality some time in the future.

Only the experience of positive temperature anomalies will be registered as indication of change if the issue is framed as global warming.

Both positive and negative temperature anomalies will be registered in experience as indication of change if the issue is framed as climate change.

We propose that in those countries where climate change has become the predominant popular term for the phenomenon, unseasonably cold temperatures, for example, are also interpreted to reflect climate change/global warming.

How about the star scientist, James Hansen who keeps telling us how global temperatures are rising when he doesn’t even know what the global temperature is:

http://data.giss.nasa.gov/gistemp/abs_temp.html

To measure surface air temperature, (SAT), we have to agree on what it is and, as far as I know, no such standard has been suggested or generally adopted.

For the global mean, the most trusted models produce a value of roughly 14 Celsius, i.e. 57.2 F, but it may easily be anywhere between 56 and 58 F and regionally, let alone locally, the situation is even worse.
(Responsible NASA Official: James E. Hansen, 2005-07-12).

Most people believe that “the science is certain” because these scientists keep saying they know more than they do. It is quite right that major policy initiatives on CO2 should be challenged when the claims are based on such flimsy evidence.