The Blanket Effect is intended for others to learn about weather modification and its related subjects in an easy to understand way. Started in 2005, this blog is a work in progress as the technology advances

November 7, 2007

Global Warming: Uncharted Terrain

(excerpt from pages 25-26: PDF)

The Age of Consequences:
The Foreign Policy and National Security
Implications of Global Climate Change
N O V E M B E R 2 0 0 7

By Kurt M. Campbell, Jay Gulledge, J.R. McNeill, John Podesta,
Peter Ogden, leon Fuerth, R. James Woolsey, Alexander T.J. lennon,
Julianne Smith, Richard Weitz, and Derek Mix

It is prudent, both intellectually and practically, to accept that the atmosphere and oceans are indeed warming, as the evidence tells us, and that this trend will accelerate in the decades ahead.

While we do not and cannot know just how much warming will occur how fast, we can safely say that the rapidity of warming currently, and in all likelihood over the next decades, has few precedents in the history of the Earth and none in the history of civilization.

No instrumental records exist for prior episodes of climate change.

The proxy evidence used for the reconstruction of climate history— palynology, foraminifera, oxygen isotopes, and other tools—can give a good but not precise idea of past temperature and precipitation patterns.

The Earth’s climate has never been static. For the past 2.7 million years, it has shown a pattern of alternating long ice ages and shorter interglacials, governed by cycles in the Earth’s orbit around the sun. (click on image at right for detail)

The last ice age was at its height around 20,000 years ago. Its end (c. 11,000-6,000 years ago) was probably crucial for human history as it coincided with the emergence of agriculture in multiple locations.

After that bout of warming—generally much slower than what we have witnessed in the last 100 years but not without sudden lurches now and again—global climate changed only modestly and slowly until the industrial age.

While our Paleolithic ancestors did have to cope with rapid climate change from time to time, when they did so the Earth had fewer people (or hominids) than Chicago has today, and they were accustomed to migrating with their scant possessions as a matter of course. Their response to adverse climate change (as to much else) was to walk elsewhere.

Since the emergence of agriculture, sedentarism, civilization, and the settlement of all habitable parts of the globe, the Paleolithic response has become more and more impractical.

Thus, while there are analogues in Earth’s history for the climate change now under way, there are none in human history.

We have entered uncharted terrain.

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