Plate Tectonics: Global Thermostat
Peter Ward has been active in Paleontology, Biology, and more recently, Astrobiology for more than 40 years. Since his Ph.D. in 1976, Ward has published more than 140 scientific papers dealing with paleontological, zoological, and astronomical topics.
He is an acknowledged world expert on mass extinctions and the role of extraterrestrial impacts on Earth. Ward was the Principal Investigator of the University of Washington node of the NASA Astrobiology Institute from 2001-2006, and in that capacity led a team of over 40 scientists and students. His career was profiled by the Pulitzer Prize winning reporter William Dietrich in The Seattle Times article "Prophet, Populist, Poet of Science."
Peter has written a memoir of his research on the Nautilus for Nautilus magazine's "Ingenious" feature entitled "Nautilus and me. My wonderful, dangerous life with the amazing Nautilus."
His books include the best-selling "Rare Earth: Why Complex Life Is Uncommon in the Universe" (co-author Donald Brownlee, 2000), "Under a Green Sky: Global Warming, the Mass Extinctions of the Past, and What They Can Tell Us About Our Future" (2007), and "The Medea Hypothesis: Is Life on Earth Ultimately Self-Destructive?" (2009).
Question: Why do you believe life may be exceptionally rare in the universe?
Peter Ward: Well, when we thought up the Rare Earth Hypothesis, it was simply taking a look at what happened on this planet that allowed us to have multi-cellularity. Part of it was that we had conditions allowing habitability for billions of years. It took a long time to get to something as simple as a two-celled creature; a long time.
How do you get a long time? You do it because system of temperature, systems of oxygen, systems of all the gasses and the carbon movement remains stable. If you get too hot, too cold and only a little bit to hot and a little bit too cold on a planetary sense, you can kiss it all good-bye. So, what is it about the earth that allowed those things to continue for such long periods of time? The most important is plate tectonics. This is the movement of the surface of the earth over the top of a mobile softer rock substrate beneath it. So, the continents skate around like bumper cars. The part of that process is a continental and ocean recycling. And that recycling system is inherently – is the absolutely necessity to keep a long term temperature constancy. We have this feedback system, a thermostat system. What makes the earth warmer is carbon dioxide, what makes the earth cooler, interesting enough is the removal of that carbon dioxide. Volcanoes put it in the air, but weathering removes it. If you take a granite, or any rock that had a volcanic material in it and let it chemically weather, one of the byproducts takes Co2 out of the atmosphere. The warmer it gets, the faster that process works. So, the warmer it gets the faster the breakdown removes Co2. If you get down to an area, or a level at which you can no longer chemically weather the volcanoes refill you up. Now that bang, bang feedback system has been in service for over 3 ½ billion years or more. That has kept us at a stable temperature.
The continental game of bumper cars known as plate tectonics is part of a global recycling system crucial to maintaining long-term temperature constancy—and giving rise to life.
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The best leaders don't project perfection. Peter Fuda explains why.
- There are two kinds of masks leaders wear. Executive coach Peter Fuda likens one to The Phantom of the Opera—projecting perfectionism to hide feelings of inadequacy—and the other to The Mask, where leaders assume a persona of toughness or brashness because they imagine it projects the power needed for the position.
- Both of those masks are motivated by self-protection, rather than learning, growth and contribution. "By the way," says Fuda, "your people know you're imperfect anyway, so when you embrace your imperfections they know you're honest as well."
- The most effective leaders are those who try to perfect their craft rather than try to perfect their image. They inspire a culture of learning and growth, not a culture where people are afraid to ask for help.
To learn more, visit peterfuda.com.