Interglacials, Milankovitch Cycles, and Carbon Dioxide

The existing understanding of interglacial periods is that they are initiated by Milankovitch cycles enhanced by rising atmospheric carbon dioxide concentrations.  During interglacials, global temperature is also believed to be primarily controlled by carbon dioxide concentrations, modulated by internal processes such as the Pacific Decadal Oscillation and the North Atlantic Oscillation.  Recent Work challenges the fundamental bases of these conceptions.

Interglacials and CO2-V2

Global Warming

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Quantum Mechanics and Motion: A Modern Perspective

Physics Essays Vol. 23, pp. 242-247 (2010)

This essay is an attempted to address, from a modern perspective, the motion of a particle. Quantum mechanically, motion consists of a series of localizations due to repeated interactions that, taken close to the limit of the continuum, yields a world-line. If a force acts on the particle, its probability distribution is accordingly modified. This must also be true for macroscopic objects, although now the description is far more complicated by the structure of matter and associated surface physics.

Quantum Mechanics and Motion-A Modern Perspective

Essays in Science
Physics

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Global Warming: A Blessing in Disguise

USA Today Magazine (November 2009)

“The real tipping point for civilization is the beginning of another Ice Age–not a world a few degrees warmer.”

USA Today Mag-Nov09

General Interest
Global Warming
Politics

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The Demystification of Emergent Behavior

Emergent behavior that appears at a given level of organization may be characterized as arising from an organizationally lower level in such a way that it transcends a mere increase in the behavioral degree of complexity. It is therefore to be distinguished from chaotic behavior, which is deterministic but unpredictable because of an exponential dependence on initial conditions. In emergent phenomena, higher-levels of organization are not determined by lower-levels of organization; or, more colloquially, emergent behavior is often said to be “greater than the sum of the parts”. This essay is intended to demystify at least some aspects of the mystery of emergence.

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Biology
Essays in Science
General Interest
Physics

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Initiatives to Enhance Nuclear Stability and Non-Proliferation in the 21st Century

Physics & Society Vol. 38, No.3 (July 2009). Coauthored with George S. Stanford.

Three initiatives that the Obama Administration can undertake that would greatly increase nuclear stability and enhance the non-proliferation regime for many years to come.

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General Interest
Nuclear Policy
Politics

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Climate Change: Sources of Warming in the Late 20th Century

The role of the North Atlantic Oscillation, the Pacific Decadal Oscillation, volcanic and other aerosols, as well as the extraordinary solar activity of the late 20th century are discussed in the context of the warming since the mid-1970s. Much of that warming is found to be due to natural causes.

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Global Warming

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Falling into the Afghan Trap

USA Today Magazine (May 2009)

The U.S. is bogged down in tactical responses to Taliban initiatives. Little by little, the Soviet experience is becoming more and more relevant.

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General Interest
Politics

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When the Stars Begin to Fall: The Waning of the Enlightenment

Essays in the Philosophy of Humanism Vol. 17 (1), Spring-Summer 2009
Creationism and Science

As fundamentalist religious thought strengthens its hold on U.S. politics, and increases its role in politics around the world, enlightened values that form the very foundation of modern society are coming under attack. In the United States the wedge issue being used by fundamentalists is a pseudo-debate over creationism and Darwin’s theory of the descent of man.

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Biology
General Interest
Politics

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The Problem of the “Prebiotic and Never Born Proteins”

It has been argued that the limited set of proteins used by life as we know it could not have arisen by the process of Darwinian selection from all possible proteins. This probabilistic argument has a number of implicit assumptions that may not be warranted. A variety of considerations are presented to show that the number of amino-acid sequences that need have been sampled during the evolution of proteins is far smaller than assumed by the argument.
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Biology
Essays in Science
General Interest

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SEAWATER pH AND ANTHROPOGENIC CARBON DIOXIDE

First chapter in Climate Change, Ed: Siddhartha P. Saikia (International Book Distributors 2010).

In 2005, the Royal Society published a report titled Ocean acidification due to increasing atmospheric carbon dioxide.  The report’s principal conclusion—that average ocean pH could decrease by 0.5 units by 2100—is demonstrated here to be consistent with a linear extrapolation of very limited data.  It is also shown that current understanding of ocean mixing, and of the relationship between pH and atmospheric carbon dioxide concentration, cannot justify such an extrapolation.

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Global Warming
Politics

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