Sunday, February 05, 2006

Scientists Now Think Global Warming Caused Greatest Extinction During At End of Permian


By Elaine Meinel Supkis

This is a schematic map of Pangea at the end of the Permian Era, 250 million years ago. The land masses were, except for at the poles, very hot, the averages at over 100 F. Scientists now think the ocean's north/south circulation shut down and the seas became too tepid and stagnant so 90% of all sea life perished while on the land, 70% of the fauna died and oxygen levels were so depressed, the air was breathable only slightly above sea level.

From Science Magazine:
Hypoxia, Global Warming, and Terrestrial Late Permian Extinctions
Raymond B. Huey* and Peter D. Ward
A catastrophic extinction occurred at the end of the Permian Period. However, baseline extinction rates appear to have been elevated even before the final catastrophe, suggesting sustained environmental degradation. For terrestrial vertebrates during the Late Permian, the combination of a drop in atmospheric oxygen plus climate warming would have induced hypoxic stress and consequently compressed altitudinal ranges to near sea level. Our simulations suggest that the magnitude of altitudinal compression would have forced extinctions by reducing habitat diversity, fragmenting and isolating populations, and inducing a species-area effect. It also might have delayed ecosystem recovery after the mass extinction.

Here is a view from above showing how oxygen was cut off by mountains so populations were isolated from each other.

This shows how low the oxygen level was relative to mountains, seen from the side.

There are many reasons for us to try to understand all the extinctions because we are bioforms here and we know we can go extinct. Of course, with lunatics whipping up wars all the time, many we will beat Mother Nature to the punch. Right?

But if sanity prevails, it does behoove us to figure out the planetary past and what dangers to keep a wary eye on. To me, this is simple when it comes to things like asteroids and comets. They are, without any doubt, grave dangers to us. Another is volcanic eruptions of mega volcanoes. Then there are more subtle but insidiously dangerous threats like destroying our air and water! And the data about global warming grows more and more dire, not less and less dangerous.

This latest information is terrifying! Not only did the planet hyper-heat, this killed off a host of sealife that produces masses of oxygen and the loss of these tiny creatures nearly killed off the luxuriant flora and fauna on land. Life existed in only a few scattered "bio-islands" and there was reduced communication between these outposts, all creatures were locked into isolation chambers until the earth cooled off again and then evolution resumed with great force and we all descended from the survivors of this ancient Noah's ark.

National Center of Atmospheric Research:
Scientists at the National Center for Atmospheric Research (NCAR) have created a computer simulation showing Earth's climate in unprecedented detail at the time of the greatest mass extinction in the planet's history. The work gives support to a theory that an abrupt and dramatic rise in atmospheric levels of carbon dioxide triggered the massive die-off 251 million years ago. The research appears in the September issue of Geology.

"The results demonstrate how rapidly rising temperatures in the atmosphere can affect ocean circulation, cutting off oxygen to lower depths and extinguishing most life," says NCAR scientist Jeffrey Kiehl, the lead author.
Thanks to increasingly powerful computers, scientists can now run detailed climatological programs that take in many more variables than ever before in order to flash forward probabliities to some sort of conclusion. So, running variables on a 50 million year scale, feeding in a small rise in CO2 each year and this was the shocking result.
18 to 54 degrees Fahrenheit (10 to 30 degrees Celsius) higher than today, and extensive volcanic activity had released large amounts of carbon dioxide and sulfur dioxide into the atmosphere over a 700,000-year period.

To solve the puzzle of how those conditions may have affected climate and life around the globe, the researchers turned to the Community Climate System Model (CCSM). One of the world's premier climate research tools, the model can integrate changes in atmospheric temperatures with ocean temperatures and currents. Research teams had previously studied the Permian extinction with more limited computer models that focused on a single component of Earth's climate system, such as the ocean.
Well, we now know the upper limit! Severe desertfication happened back then. The reason why we have so much oil to pump is because of all that lush biomass rotted and was quickly covered by sand and gravel and then compressed by mud from rising seas. We are literally repeating the mess of the Permian extinction by burning the rotted carcasses of the living creatures who dwelled on this earth so long ago.
The CCSM's simulations showed that ocean circulation was even more stagnant than previously thought. In addition, the research demonstrated the extent to which computer models can successfully simulate past climate events. The CCSM appeared to correctly capture key details of the late Permian, including increased ocean salinity and sea surface temperatures in the high latitudes that paleontologists believe were 14 degrees Fahrenheit (8 degrees Celsius) higher than present.
Understanding the dynamics of the ocean currents is important and scientists already fear the mighty Gulf Stream is weakening due to nonsalty water draining off of Greenland.

From this blog:
The most recent study of the Atlantic currents show weakening of the rate of flow. Some scientists have speculated that a slower current could trigger a sudden ice age if all other meteorlogical and solar actions coincide to produce a plunge in the northern jet stream. The debate about this oscillation possibility rages on. Understanding this process is vital for our survival.
Back when I wrote this, I didn't know the new information. This is far more alarming.

The great Siberian eruptions occured at the end of the Permian and this was like Mother Nature running a huge SUV non stop. She does what She does but we can't be that fatalistic, we have to do the right thing, not the wrong thing, since it pays off handsomely, namely, we get to live on as organisms.

As usual, we take tiny steps forwards, here is an example, the British are getting kind of worried since they are on the front lines of so many bad things here (forget Florida or any Gulf state, they are doomed). From the BBC:
Governments are wrestling with problems of rising energy demands, rising costs and the spectre of climate change. In this week's Green Room, Dr Matt Prescott argues there is an easy first step to dealing with all three issues - banning the traditional light bulb.
Ever since I began to use solar energy, I used only fluorecent bulbs. I never use the cheap bulbs. I agree they should be outlawed but bet this will never happen any more than people will respond by doing the right thing rather than the destructive, cheap thing. This is why people are going to be caught in a trap of their own devising.

Simple things like building houses facing the optimal direction for solar heating or keeping cool depending on the climate, is a no-no nearly universally in this country. I must be living on one of all of 1% of houses deliberately sited and designed to maximize natural forces to my benefit. This is woeful and suicidal, our building for no future. Even if we build vast bubbles to protect us, the planet will die around us and end up with less oxygen than Mars.
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