In one fell swoop, global cooling has become global warming. Amazing!!

"Although the cause of the Permian mass extinction remains a debate, numerous theories have been formulated to explain the events of the extinction. One of the most current theories for the mass extinction of the Permian is an agent that has been also held responsible for the Ordovician and Devonian crises, glaciation on Gondwana. A similar glaciation event in the Permian would likely produce mass extinction in the same manner as previous, that is, by a global widespread cooling and/or worldwide lowering of sea level."

However, as stated in the article, global warming has superceeded global cooling as the cause of mass extinctions at the end of the Permian: The largest mass extinction event of all, the end-Permian, occurred during one of the warmest ever climatic phases and saw the estimated extinction of 95 per cent of animal and plant species.

Looks like we have a bit of a problem here. I'm also amazed that K-T extinction event has now been attributed to greenhouse gases instead of a meteor impact. That's a bit of a stretch. From what I've seen temperatures were pretty even across the K-T boundary and CO2 concentrations were declining.

I would say that we'll just add this to the list of possible causes of the mass extinctions.

Complete nonsense. CO2 was 10X current levels during the Jurassic, when biodiversity was at a maximum. The dinosaurs were killed by cold - not heat.

Reply: Do you have a link that supports your claim? I am not saying it is right or wrong, just wondering, since that would certainly water down the claims of the study. Brett

I always thought the largest mass extinction had to do with the entire earth being a giant ball of ice and only some scattered plant life in the ocean survived??? That's what I get for watching national geographic, or was it the science channel? I forget, but it was one of those two.

So C02 is the down fall of us all. Darn it, I always thought it would have been a commet, gamma ray burst, or the helium flash of the sun when it turns into a red giant. But no, the exhaust coming out of our tail pipes and our mouths will do it, who knew?

I have to get to class, I have some green screen practice today... (ill be back :)

Really hate to respond to press releases which do not contain many details.

Of course with so much pollution, habitat destruction and illegal poaching, there is already an extinction event underway. Global Warming is just another factor on top.

I'm not an expert, but I do have a B.S. on biology, so I'm not completely ignorant, either. I've always had a problem with guaging the health of an ecosystem solely by biodiversity. I think that it is completely legitimate to look at ecosphere health by another criterion, namely, total biomass. I mean to say that I'm more interested in the total amount of living matter as a function of time. I'm not saying that biodiversity is unimportant, because, in the ppast, a healthy ecosystem with high net productivity was extremely unlikely to have low species diversity.
For example, it seems that human beings as a species have tended to have a negative impact on species diversity, but I'd like to know what impact, if any, ee have had on earths net productivity. WE've destryed habitats and caused the extinctions for countless organisms, but our activities have also probably allowed species such as rats, cattle, chickens, hogs, ceral grains to be more successful than they otherwise would have been. I want to know if human impact is causing the earth to support less life, or just less KINDS of life.

Brett,

Some studies indicate that CO2 levels were nearly 3000ppm in the Jurassic (compared to 380ppm now) and temperatures were about 10C higher.
http://mysite.verizon.net/mhieb/WVFossils/PageMill_Images/image277.gif

Patrick, based on your graph it seems that as the CO2 levels were relatively low during the first part of the Jurassic then were higher the second half.

Other studies put Jurassic CO2 at 4x current levels.
http://www.pnas.org/cgi/reprint/99/7/4167.pdf

All studies show current CO2 levels much lower than any other time in geological history. The "consensus" has dinosaur extinction due to an asteroid impact which created a "nuclear winter" like climate for a few years.

The widespread rumor that one degree is a "tipping point" doesn't have any support in the geological record.

Daniel Botkin, president of the Center for the Study of the Environment and professor emeritus in the Department of Ecology, Evolution, and Marine Biology at the University of California said this recently in an article:

"Case in point: This year's United Nations report on climate change and other documents say that 20%-30% of plant and animal species will be threatened with extinction in this century due to global warming -- a truly terrifying thought. Yet, during the past 2.5 million years, a period that scientists now know experienced climatic changes as rapid and as warm as modern climatological models suggest will happen to us, almost none of the millions of species on Earth went extinct. The exceptions were about 20 species of large mammals (the famous megafauna of the last ice age -- saber-tooth tigers, hairy mammoths and the like), which went extinct about 10,000 to 5,000 years ago at the end of the last ice age, and many dominant trees and shrubs of northwestern Europe. But elsewhere, including North America, few plant species went extinct, and few mammals."

Brett,

I'm not sure what you mean by "relatively low" CO2 levels in the Jurassic. Reply: I did not mean compared to today, but looking at the whole chart, and also comparing it to the late Jurassic. Brett. The lowest point was 300% current levels and the highest point was >600% current levels. Neither inflection was associated with any widespread extinctions.

Consider the current hysteria over a 30% change. Here is another CO2 reference
http://www.ldeo.columbia.edu/~polsen/nbcp/rationale.html

Please everybody click on and read the press release. Think what was said and Then ask yourselves
Where is the science?
Where is the causality?
And how did Global warming cause any of these extinctions?

The five worst mass extinctions:

"Cretaceous-Tertiary — roughly 65 million years ago. Probably caused or aggravated by impact of large asteroid…."

All other reports claim an “Asteroid Winter” with acid rain and no photosynthesis caused the extinctions. How does Global Warming get into the mix?

"End-Triassic — roughly 200 to 214 million years ago. Most likely caused by massive floods of lava erupting from the central Atlantic magmatic province — an event that triggered the opening of the Atlantic Ocean. The volcanism may have led to deadly global warming….."

I thought the eruption at Mt. Pinatubo, Philippines – 1991 caused the earth to cool because of all the particulates sent into the heavens blocking sunlight. Now we see volcanoes cause global warming because???????.
I get it:
One volcano blocks sunlight cools the earth
Many volcanoes: get you grant money to make extravagant claims as long as you blame it on Global Warming.
Call me silly but just maybe massive floods of lava made it kind of hard to live on the planets surface and find food. Alas the culprit must be Global Warming not the sulfur dioxide or the massive change in the geography

"End-Permian — about 251 million years ago. Cause hotly debated."

On this extinction they don’t even offer a clue except it must be Global warming.

"Late Devonian — about 364 million years ago. Cause unknown."

Since we don’t know the cause it must be global warming.

"Ordovician-Silurian — 439 million years ago. Caused by a drop in sea levels as glaciers formed, then by rising sea levels as glaciers melted."

I get it. Glaciation undoubtedly caused by Global warming because of (dare I say it??) farting moose????

So where does Global Warming do anything???? It seems as if cooling not heating was the major culprit.

This is sheer nonsense.

Note: The department which was largely responsible for this article at the University of Leeds happens to be funded to the tune of 180K pounds sterling a year by endowments (source(s) not named). "In September 2006 the University adopted its Carbon Management Plan (CMP). This was developed by staff and students with the Carbon Trust. Its primary focus is to reduce carbon dioxide emissions."

No oil toadies on this campus. NO science either……Just your everyday unbiased committed Greenie.

Absurd!!!Simply Absurd!!!

Brett,

Fair enough - but if we compare current CO2 vs. say the Cambrian (7000ppm), it hardly even registers. (Reply: no argument there.) The small deltas (100ppm) which Hansen is warning us about are in the noise over the period which life has existed on the earth.

Not to say that the climate isn't continuously changing and that CO2 levels don't affect it, but the warnings of mass extinctions and Antarctica melting seem overblown when considered historically.

Patrick Henry,

Welcome back! Your last link is a good source of information.

This graph is particular useful and shows the correlation between flood basalts and extinctions over the last 150 million years. But, unfortunately, this does not go well with the CO2 causes everything mantra being spouted by the Gorewellians. Don't you just hate it when that happens?

PH:
excellent links.
I have seen these and many more like them.
It is clear that today's CO2 levels are unusually low in the overall history of our world.
I am thinking that a level of around 2000 ppm would be on the whole, much better all around.
I will go our this weekend and see if I can get a Hummer so that I can do my part to get us back to some sort of global optimum climate.
Would all of you please do the same?
Thanks