Skip to comments.Spiegel speculates on why global warming stalled
Posted on 01/28/2013 1:52:04 PM PST by Ernest_at_the_Beach
click here to read article
Thought you might to read this link - http://en.m.wikipedia.org/wiki/Milankovitch_cycles
Milankovitch cycles and a variety of other phenomena such as the Earth’s other orbital mechanics, rotational precession, magnetic pole reversals, lengthening diurnal rotation (longer days), reducing lunar tidal forcings, and so forth represent much smaller and shorter influences when compared to the vastly larger changes in atmospheric mass and composition by inorganic and organic influences. There are for some examples the expression of the Milankovitch cycles in the varves of the Devonian, when the development of the first forests upon the Earth radically increased the concentration of oxygen in the atmosphere while more than halving the already trace amounts of carbon dioxide, which resulted in another major ice age and a mass extinction event. When you are doing geological field work, you can see in the varves how the water levels changed in synchronization with the Milankovitch cycles, but the far larger events ended these sequences with overwhelming changes to the geomorphology, sea levels, and related biosphere. It is always provocative to see the media go on about the Milankovitch cycles in connection to the stages of the curreent ice age while totally neglecting the many other vastly more forceful changes in the Earth’s inherent composition and solar luminosity.
Thank you for your knowledge on the subject! I was up pretty late reading all kinds of different stuff as this was the first I had heard of the Milankovitch cycles. Being an engineer and understanding that nothing is absolute and has some certain tolerance band, i.e. our orbit around the sun, the Earth’s axis tilt, it got me thinking about how these tolerances, coupled with the sunspot cycle, may have affected climate changes in the past. Your additional information is really valuable.
Its also cool that they are studying the same stuff on Mars. Kinda blows a hole in the MAN-MADE theory when man has never set foot on Mars.
Mars and Venus are examples which hold great interest. Hansen, NASA GISS, is notorious for his use of Venus as an example of Earth’s fate if the purported Climate Change is not immediately halted by stopping usage of fossil fuels. His political stance and bogus science are very bizarre indeed when you look at how the atmospheres of Venus, Earth, and Mars deveeloped.
Venus has a truly massive atmosphere dominated by carbon dioxide. This is especially interesting for a number of reasons, including the similarities between the atmosphere of Venus compared to the Early second atmosphere of the Earth. Both atmospheres featured the crushingly massive carbon dioxide atmosphere, but Earth’s biosphere consumed all but trace levels at parts per million of the carbon dioxide and depostied it into the lithosphere and released parts of the oxygen into the atmosphere. On Venus, we can see empirical evidence that the massive carbon dioxide was not consumed by a biosphere and thereby reduced to levels of 1 percent of its early mass and carbon dioxide composition.
When we look at Mars, we again find a planet with a predominately carbon dioxide atmosphere. Unlike Venus, however, Mars lacked the gravity necessary to retain its earlier and more massive atmosphere. The Solar winds have accelerated much of the Martian atmosphere to escape velocity and stripped it off into inter-planetary space. If Mars had ever developed carbon based lifeforms like Earth or provided a home to lifeforms with an origin on the Earth, it would seem most likely any aerobic lifeforms should have consumed and removed all but trace levels of carbon dioxide from the thinning Martian atmosphere. Instead we see today a thinned Martian atmosphere that is still dominated by the carbon dioxide life would have removed.
Speculation would seem to require a proper explanation for how a planet hosting carbon based lifeforms related to the basic chemistries and physics of liquid water and atmospheric dioxide would or could fail to remove nearly all carbon dioxide from a planetary atmosphere?
To find Earth-like life on exoplanets, it would seem likely that the planet must not have a substantial primordial carbon dioxide atmosphere, because the lifeforms would have consumed and removed it from the atmosphere. The biochemistry of the lifeforms seems to require it.
Hansen is also wrong about Venus, when you consider that the massive concentrations of carbon dioxide still result in comparable air temperatures at the higher levels of the Venusian atmosphere where the atmospheric pressure is comparable to Earth’s surface atmospheric pressure.
If the other planets harbor life, it would seem the life would tend to be anaerobic, poisoned by exposures to oxygen.
These videos on YouTube may be of some interest.
Why Mars Died, and Earth Lived
Cosmic Journeys : Mars: World That Never Was .
Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.