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Wednesday, August 6, 2008

A question about heat...

I just sent the following to will post response as soon as it arrives.

Conversion of chemical to radiative heat...

What determines the rate at which chemical heat (convection) becomes electromagnetic heat (radiation)?  I am trying to get a handle on the Earth's energy budget.  Obviously, heat is being transfered in-system through convection... but what is the process that converts this chemical heat (brownian motion that needs a material medium) to photonic heat (that can leave the planet and travel through space)?  What factors limit this phase transition?  In terms of total energy transfer, how can one determine the delta between the rate of transfer (comparing convection and radiation) when a system has both.  What are the limits of efficiency when comparing both chemical and radiative energy transfer?  I know that convection is restricted by the sound limit, so I assume that radiative heat is likewise restricted by the speed of light.  However, because light doesn't seem to interact with other light, how dense does light have to be before we see dramatic self limiting effects?  I am guessing that E=mC^2 will answer my question as dense light becomes matter which provides the upper limit to the speed of light?  All of my questions are motivated by a desire to understand the base physics that underlies and predicts the Earth's energy budget and how these natural systems are effected by green house gasses and human energy conversion (releasing heat), especially with regard to the ratio of rate of change vs. dissipative capacity of the natural systems.

Thank you,

Randall Reetz

Laurence Lessing's "Independence 2.0"

An important reflection on how big oil money has influenced public perception of climate change science:

Or consider perhaps the most profound misfiring of modern American government—global warming. Davis Guggenheim's film of Al Gore's An Inconvenient Truth lecture was a tipping point in public recognition of the threat global warming presented to America and the world. But that tipping point came long after a consensus had developed among policy experts about the threat of global warming. As Gore describes the consensus:

The debate's over. There are five points in the consensus. No. 1: Global warming is real. No. 2: We human beings are mainly responsible. No. 3: Consequences are very bad. No. 4: We need to fix it quickly. And No. 5: It's not too late.

Researchers have tried to measure just how solid this consensus is. They conducted a study of 1,000 articles published in peer-reviewed journals between 1988 and 2003. Of the 1,000, 0 percent (or exactly 0) questioned the consensus around global warming. Yet a comparable study of articles published in popular news media found over 53 percent questioned that consensus.

The difference is accounted for by the extraordinary effort by oil companies and the like to fund and spread the results of junk science, questioning global warming in a manner that threw certain views into doubt. The result was political cover for the Republican Party's campaign of Global Warming Denial.

As strategist Frank Luntz put it in a memo to Republican leaders, 

"Should the public come to believe that the scientific issues are settled, their views about global warming will change accordingly. Therefore, you need to continue to make the lack of scientific certainty a primary issue in the debate."

The list could go on—for a very long time. None of these questions are rocket science. Not all are esoteric matters about the regulation of culture. Indeed, some are among the most important public policy questions government considers. Yet all these, despite the ease, government got wrong. And wrong in a predictable way—the product of a dependency tied to money. Among the reasons for reform, this certainly reaches quite high.

This is an excerpt from an essay on the dangers of monetary influence on our government representatives by Stanford University copyright law professor Lawrence Lessig (Independence 2.0, MetroActive, 8/6/08).

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