Mammoths, mastodons, saber-toothed cats, glyptodonts, and other great beasts roamed the land of North America, Europe, and Asia, until something happened about 12,000 years ago. Just what that something was, is subject to great debate. We will focus on the case in North America.   

Hypotheses attempting to explain the extinctions include: The mammoth hunters “is wot done it”, disease, normal climate change at the end of the glacial epoch, and abrupt climate change caused by a big flood or a comet strike.   

Here is what we do know. Humans (of the Clovis Culture) entered North America at least 13,500 years ago when abundant megafauna inhabited the land. The planet was warming up from the last glacial epoch and had reached temperatures similar to today. Between about 12,900 and 11,500 years ago there was an abrupt cooling episode called the Younger Dryas (after a small Arctic flower), during which global temperatures plunged, in a matter of decades, from temperate climes to near glacial conditions. It stayed cold for about 1,400 years then rapidly warmed again. During that time, most of the megafauna became extinct. Evidence of the human Clovis culture also disappeared.   

That point in time about 12,000 years ago, the end of the Pleistocene epoch, is marked in many places with a “black mat” of rich organic material. Below the mat are abundant fossils of megafauna and artifacts of the Clovis culture. No such fossils and few, if any, Clovis artifacts are reported above the black mat.   

A study of the black mat at 50 Clovis sites in North America found a “discrete layer with … magnetic grains with iridium, magnetic microspherules, charcoal, soot, carbon spherules, glass-like carbon containing nanodiamonds, and fullerenes with ET helium, all of which are evidence for an ET impact and associated biomass burning at 12.9 ka.”   

Let’s examine the hypotheses: (more…)

The Energy Gap is a tour de force review of our energy resources, their potentials, pitfalls, environmental consequences, economics, and politics. The sub-title is “How to solve the world energy crisis, preserve the environment & save civilization.” Well not quite, but it is a start.

After three introductory chapters, the book devotes chapters, in turn, to coal, petroleum, natural gas, wind, solar, and green energy sources such as hydroelectric, geothermal, biomass, and tidal wave power. There are three chapters on nuclear energy including an explanation of the various types of nuclear reactors and the problems of waste disposal. Additional chapters are devoted to transportation, the energy grid, conservation & efficiency, and the politics of energy.

For each form of energy the authors delve into the history of formation, discovery, development, use, and reserves. The book contains over 200 illustrations, and five appendices. It is written in layman’s terms.

The authors promote nuclear energy and suggest that it should gradually replace coal as the major fuel for electrical generation. Although the U.S. has the highest installed wind generating capacity of any nation, about 25,000 MW, the authors say that wind and solar are not likely to become a significant resource because of the very high cost relative to fossil fuels, and because both wind and solar are intermittent and cannot be counted on to provide a steady peak generation capacity. They do promote these alternative types of energy production in niche markets which might have special advantage.

The authors are somewhat naive about mineral economics and worry that we will run out of fossil fuels before we fully develop alternatives. But “the harsh reality is that, other than hydroelectric power, most renewable technologies are not able to compete economically with fossil fuels.”

They present an energy plan which includes:

Use of renewable energy only where it makes sense.

Shift automobile and light truck production to hybrids and electric. This would increase need for electricity by about 15%. (The only reason for this shift is the author’s unsupported belief that we should reduce carbon dioxide emissions. I think this is impractical and people will not buy electric cars until battery technology makes it possible to go 500 miles between charges.)

Accelerate construction of new nuclear generating stations and add reactors to existing plants.

Make buildings more energy efficient.

Expand exploration for oil and natural gas which “will be needed until new nuclear plants can come on-line and our vehicle fleet is switched to electricity.”

The authors specifically say we should avoid biofuels because they cause more environmental damage than fossil fuels. They warn against “clean coal” because the infrastructure costs are too high and the possible hazardous effects of storage are too uncertain. (See my article “Clean Coal”: Boon or Boondoggle for background.

They also warn against methane clathrates because they think frozen deposits of natural gas are too risky to exploit.

While I disagree with some of their proposals, I recommend the book just for its extensive review of energy resources. The book is very up to date on energy technology and even discusses the Gulf oil spill.

The book is available at Amazon.com. The authors also maintain a very interesting website: The Resilient Earth.

For another take on the energy problem see A Free Market Energy Vision from MasterResource.

This is a guest post by Dr. Harrison Schmitt, former United States Senator from New Mexico as well as a geologist and former Apollo Astronaut. This is a good review of the natural climate change that the planet has experienced. Dr. Schmitt says:

Americans should think long and hard about their children’s future before giving up liberties and incomes to politicians in Washington and at the United Nations in the name of “doing something” about climate change. Given how little we actually know about climate, as well as great uncertainties in what we do know, the President, regulators, and Congress have chosen an extraordinarily dangerous path of unconstitutional usurpation of the rights of the people and the constitutionally reserved powers of the States.

Climate change assumptions rather than facts, and computer modeling rather than real-world observations, underpin the Government’s efforts to restrict American liberties and confiscate trillions of dollars of American income. The scientific rationale behind this proposed massive intrusion into American life requires more than a “consensus” of like-minded climate analysts and bureaucrats. It needs to be right.

Ten thousand years of natural, post-Ice Age climate variability should give pause to those who maintain that current slow global warming and carbon dioxide increases result largely from human use of fossil fuels. Public confidence in that position also suffers from the exposure of fraudulent academic and bureaucratic behavior aimed at overriding normal processes of skeptical scientific review and debate.  (more…)