How do you feel about snowball earth and the reasoning behind it?

[ScienceRocks]

Westwall,

Would you post a video of you speaking about geology. I love watching science and everything about our planet.

 

[westwall]

The fact remains that ALL empirical evidence shows that CO2 lags temperature by hundreds of years.

If conditions in the present are different, the present will not act like the past.

For some reason, that very basic logic is something denialists have never been capable of grasping. That's the main reason why they're laughed at in the world of science. Scientists are good at logic, so they instantly recognize how awful the logic of the denialists is.

Incorrect. The present Always follows the past. Always has, and always will. That's what physics does for you. Physical laws are immutable. They MUST react the same. Put another way, the same CO2 is on this planet as was here when it was created. NOTHING has been added.

 

[westwall]

While there is debate as to whether these events involved a total snowball Earth, there is no debate about that fact that these were periods of extreme glaciation. Glaciers down to sea level at the equator. And the proxies from those periods indicate major reductions in GHGs at the same time. Just as when we see periods of very fast heating of the Earth, the proxies indicate that there were major increases in GHGs at the same time.

Richard Alley: "The Biggest Control Knob: Carbon Dioxide in Earth's Climate History" - YouTube

And those same proxies also show that the CO2 levels fluctuated by vast amounts over thousands of years all during the periods of glaciation. Conversely those same proxies also show warm periods with low CO2 concentrations. In fact you posted one of these studies a few years ago and when I pointed out to you that it didn't support your cause you "disappeared" it along with anything else that doesn't support your pre-conceived ideas.

The fact remains that ALL empirical evidence shows that CO2 lags temperature by hundreds of years. The overwhelming evidence also shows that no mass extinction event can be attributed to warming. The one warming event that we have very good evidence of, namely the PETM, shows that the entire world (with the exception of some benthic forams, who's demise is attributed to anoxic conditions in their very localized areas) bloomed. There is ZERO empirical evidence to show that warmth has EVER been bad for the planet. Absolutely none.

Phd geologist? The proxies indicate strong rise in GHGs before both the PT event and the Tertiary event.

The Permian-Triassic Extinction - Volcanism and the Great Dying

Consider the stressed biosphere late in the Permian: low oxygen levels restricted land life to low elevations. Ocean circulation was sluggish, raising the risk of anoxia. And the continents sat in a single mass (Pangea) with a reduced diversity of habitats. Then great eruptions begin in what is Siberia today, starting the largest of Earth's large igneous provinces (LIPs).

These eruptions release huge amounts of carbon dioxide (CO2) and sulfur gases (SOx). In the short term the SOx cools the Earth while in the longer term the CO2 warms it. The SOx also creates acid rain while CO2 entering the seawater makes it harder for calcified species to build shells. Other volcanic gases destroy the ozone layer. And finally, magma rising through coal beds releases methane, another greenhouse gas.

With all of this happening to a vulnerable world, most life on Earth could not survive. Luckily it has never been quite this bad since then. But global warming poses some of the same threats today

I prefer this discussion on the extinction event. It has no internal bias. Climate change is addressed and cold comes out as a possible cause by a margin of four to one against warming as a cause. Further the largest sea level drop ever recorded occurred at the end of the Permian further reinforcing the theory that it was glaciation that was a proximal cause of extinction.


http://palaeo.gly.bris.ac.uk/palaeofiles/permian/intro.html

 

[westwall]

Westwall,

Would you post a video of you speaking about geology. I love watching science and everything about our planet.

I don't recall if I was ever recorded during my academic career to be honest. I do know there is footage of me testifying in court as an expert witness but those tend to be locked up by the litigants. I'll see if I can find anything out there.

 

[percysunshine]

How do you feel about snowball earth and the reasoning behind it?

...

There's like 3 video's about it...So I agree with the one about the methane being taken out of the atmosphere from the first "life" that put oxygen into the atmosphere 650 million years ago. This only ended when the volcano's released extreme amounts of co2 into the atmosphere.

Shit Happens

...slowly in human life spans.

.

 

[JimBowie1958]

That "fudge factor" was used for sanity testing the code, not generating data.
That is, your sources lied their asses off about the "fudge factor". But you don't care, being that you're a loyal cultist.

Prove it.

Pay me first. I only educate people willing to be educated.

Okay, I'll be generous. If, after I show you, you promise to apologize, condemn your source for outright lying and to never use them again, I'll do the work for you. Deal? That's reasonable. After all, you shouldn't be allowed to just slink away afterwards, pretend it never happened, and go right back to using that liar source.

You made the accusation that these men were lying; either prove it or show some dignity and stop slandering them.

And of course, if you convince me that this 'fudge factor' was not being used to hide the warming in the 1930s - 1940's, I would change my mind, state any apologies I think warranted and stop referring to it. It is called having the integrity to be honest with myself.

You should try it sometime.

 

[mamooth]

Incorrect. The present Always follows the past. Always has, and always will.

Let's give some examples of that very peculiar logic.

"In the past, temps followed CO2. Since the present must be like the past, humans adding CO2 can not change global temperature."

"In the past, species went extinct without human intervention. Since the present must be like the past, human actions can have nothing to do with species going extinct."

It's really awful logic. Hence all scientists roll their eyes when it's invoked, shocked that anyone could think that way.

That's what physics does for you. Physical laws are immutable. They MUST react the same. Put another way, the same CO2 is on this planet as was here when it was created. NOTHING has been added.

Atmospheric conditions are not like the past. Things are different. Therefore, those immutable physical laws say the result must be different.

 

[mamooth]

You made the accusation that these men were lying;

It's WUWT, so of course they're lying. There are whole websites devoted just to laughing at WUWT lies. Here's a fun one.

HotWhopper

either prove it or show some dignity and stop slandering them.

You tossed out the accusation that the scientists were lying. Hence, by your own standards, you are responsible for proving it. You haven't. You've shown a snippet of code taken from vast mountains of code. You haven't shown any evidence to link that bit of code to any published results.

You won't be able to do that, since it was there for sanity checking the algorithm, and was not used for any published results. I could show exactly how that was done, painfully explaining the programming ... but it would literally take hours, and I don't have to do it. You made the positive assertion, so the burden is on you to either prove it or retract it. You need to show us the precise data trail from that code to published results.

And of course, if you convince me that this 'fudge factor' was not being used to hide the warming in the 1930s - 1940's, I would change my mind, state any apologies I think warranted and stop referring to it. It is called having the integrity to be honest with myself.

I doubt it's possible to convince you, since you've already made up your mind. but consider this. That snippet of code was from 1998. Yet all the data since, none of which used the same code, basically agrees with it. Is it your contention that essentially all the climate science code in the world has been continuously faked for 25 years running? If you're that deep into the wacky conspiracy theory, I won't be able to pull you out.

 

[JimBowie1958]

You made the accusation that these men were lying;

It's WUWT, so of course they're lying. There are whole websites devoted just to laughing at WUWT lies. Here's a fun one.

HotWhopper

either prove it or show some dignity and stop slandering them.

You tossed out the accusation that the scientists were lying. Hence, by your own standards, you are responsible for proving it. You haven't. You've shown a snippet of code taken from vast mountains of code. You haven't shown any evidence to link that bit of code to any published results.

I am not trying to show where it was used, but only that it was there at all. No one writes functions like that and not use them, dimwit.

You won't be able to do that, since it was there for sanity checking the algorithm, and was not used for any published results. I could show exactly how that was done, painfully explaining the programming ... but it would literally take hours, and I don't have to do it.

Bullshit. Adjusting the historical record has nothing to do with sanity checks, moron, by definition. A sanity check in programming means you get data that is raw and untouched to make sure your results are within range of reason. That is not accomplished by faking numbers.

You made the positive assertion, so the burden is on you to either prove it or retract it. You need to show us the precise data trail from that code to published results.

I did show the evidence, but you reject it via ad hominem.

I don't really care what you think as I feel confident that most objective readers will see how full of shyte you really are and decide for themselves.

And of course, if you convince me that this 'fudge factor' was not being used to hide the warming in the 1930s - 1940's, I would change my mind, state any apologies I think warranted and stop referring to it. It is called having the integrity to be honest with myself.

I doubt it's possible to convince you, since you've already made up your mind. but consider this. That snippet of code was from 1998. Yet all the data since, none of which used the same code, basically agrees with it. Is it your contention that essentially all the climate science code in the world has been continuously faked for 25 years running? If you're that deep into the wacky conspiracy theory, I won't be able to pull you out.

No, not all just the one locale, but similar problems with data being lost corrupted, faked, etc, have popped up among AGW fraudsters all over the world, from glaciers that aren't really melting to polar bears that are not drowning to Australian temperature records that no longer include the raw data at all.

 

[Old Rocks]

And those same proxies also show that the CO2 levels fluctuated by vast amounts over thousands of years all during the periods of glaciation. Conversely those same proxies also show warm periods with low CO2 concentrations. In fact you posted one of these studies a few years ago and when I pointed out to you that it didn't support your cause you "disappeared" it along with anything else that doesn't support your pre-conceived ideas.

The fact remains that ALL empirical evidence shows that CO2 lags temperature by hundreds of years. The overwhelming evidence also shows that no mass extinction event can be attributed to warming. The one warming event that we have very good evidence of, namely the PETM, shows that the entire world (with the exception of some benthic forams, who's demise is attributed to anoxic conditions in their very localized areas) bloomed. There is ZERO empirical evidence to show that warmth has EVER been bad for the planet. Absolutely none.

Phd geologist? The proxies indicate strong rise in GHGs before both the PT event and the Tertiary event.

The Permian-Triassic Extinction - Volcanism and the Great Dying

Consider the stressed biosphere late in the Permian: low oxygen levels restricted land life to low elevations. Ocean circulation was sluggish, raising the risk of anoxia. And the continents sat in a single mass (Pangea) with a reduced diversity of habitats. Then great eruptions begin in what is Siberia today, starting the largest of Earth's large igneous provinces (LIPs).

These eruptions release huge amounts of carbon dioxide (CO2) and sulfur gases (SOx). In the short term the SOx cools the Earth while in the longer term the CO2 warms it. The SOx also creates acid rain while CO2 entering the seawater makes it harder for calcified species to build shells. Other volcanic gases destroy the ozone layer. And finally, magma rising through coal beds releases methane, another greenhouse gas.

With all of this happening to a vulnerable world, most life on Earth could not survive. Luckily it has never been quite this bad since then. But global warming poses some of the same threats today

I prefer this discussion on the extinction event. It has no internal bias. Climate change is addressed and cold comes out as a possible cause by a margin of four to one against warming as a cause. Further the largest sea level drop ever recorded occurred at the end of the Permian further reinforcing the theory that it was glaciation that was a proximal cause of extinction.


Palaeobiology and Biodiversity Research Group, Department of Earth Sciences, University of Bristol

Palaeobiology and Biodiversity Research Group, Department of Earth Sciences, University of Bristol


Isotopes and climate
Isotopes across the PTB and climate change

A major objective on the 2004 expedition was to take samples for isotopic analysis. The key isotopes are those of oxygen and carbon. At the PTB, there is a dramatic shift in oxygen isotope values of marine carbonates, a decrease in the value of the δ18O ratio of about six parts per thousand (ppt), corresponding to a global temperature rise of about 6oC. Climate modellers have shown how global warming can reduce ocean circulation and the amount of dissolved oxygen, creating anoxia in the oceans; this is seen in marine sediments from around the world. The marine evidence for anoxia nearly world-wide is dramatic and convincing, and this episode of superanoxia, which surely killed much of the life on the sea bottom (Wignall & Twitchett, 1996), must form part of any model for events at the PTB.
Carbon isotopes have been hugely important in determining models for the PT mass extinction. Geochemists measure the ratio of the stable isotopes 13C and 12C in limestones and fossil shells, and even in carbonate palaeosols. In nature, most carbon occurs as 12C, with minor, but measurable, amounts of 13C. The ratio of these two isotopes in the atmosphere is the same as in the surface waters of the oceans. During photosynthesis, plants preferentially take up 12C to produce organic matter. If this organic matter is buried, rather than returned to the atmosphere-ocean system, then the atmosphere-ocean 13C: 12C ratio will shift in favour of the heavier isotope. Conventionally, this ratio is expressed as δ13C, which is the difference between the 13C: 12C ratios in the sample being tested and in a known standard.

In the ocean system, during times of high surface productivity, large amounts of organic matter are fixed at the surface and the surface waters of the ocean become (relatively) enriched in 13C. Shallow-water carbonate deposits are precipitated from this seawater, and record the seawater 13C: 12C ratio without any preferential uptake of one or other isotope. Therefore, during times of high surface productivity, shallow water carbonates record a positive shift in δ13C (i.e. towards the heavier isotope).

The PTB is characterized by a negative shift in δ13C, which is recorded in the carbonate deposits of all geological sections studied so far (e.g. Magaritz et al. 1988; Sephton et al., 2002), including terrestrial ones (Retallack 1995; MacLeod et al. 2000). On the face of it, this should imply a massive decrease in biological production and rate of burial of organic matter.

 

[Old Rocks]

And those same proxies also show that the CO2 levels fluctuated by vast amounts over thousands of years all during the periods of glaciation. Conversely those same proxies also show warm periods with low CO2 concentrations. In fact you posted one of these studies a few years ago and when I pointed out to you that it didn't support your cause you "disappeared" it along with anything else that doesn't support your pre-conceived ideas.

The fact remains that ALL empirical evidence shows that CO2 lags temperature by hundreds of years. The overwhelming evidence also shows that no mass extinction event can be attributed to warming. The one warming event that we have very good evidence of, namely the PETM, shows that the entire world (with the exception of some benthic forams, who's demise is attributed to anoxic conditions in their very localized areas) bloomed. There is ZERO empirical evidence to show that warmth has EVER been bad for the planet. Absolutely none.

Phd geologist? The proxies indicate strong rise in GHGs before both the PT event and the Tertiary event.

The Permian-Triassic Extinction - Volcanism and the Great Dying

Consider the stressed biosphere late in the Permian: low oxygen levels restricted land life to low elevations. Ocean circulation was sluggish, raising the risk of anoxia. And the continents sat in a single mass (Pangea) with a reduced diversity of habitats. Then great eruptions begin in what is Siberia today, starting the largest of Earth's large igneous provinces (LIPs).

These eruptions release huge amounts of carbon dioxide (CO2) and sulfur gases (SOx). In the short term the SOx cools the Earth while in the longer term the CO2 warms it. The SOx also creates acid rain while CO2 entering the seawater makes it harder for calcified species to build shells. Other volcanic gases destroy the ozone layer. And finally, magma rising through coal beds releases methane, another greenhouse gas.

With all of this happening to a vulnerable world, most life on Earth could not survive. Luckily it has never been quite this bad since then. But global warming poses some of the same threats today

I prefer this discussion on the extinction event. It has no internal bias. Climate change is addressed and cold comes out as a possible cause by a margin of four to one against warming as a cause. Further the largest sea level drop ever recorded occurred at the end of the Permian further reinforcing the theory that it was glaciation that was a proximal cause of extinction.


Palaeobiology and Biodiversity Research Group, Department of Earth Sciences, University of Bristol

Palaeobiology and Biodiversity Research Group, Department of Earth Sciences, University of Bristol


Isotopes and climate
Isotopes across the PTB and climate change

A major objective on the 2004 expedition was to take samples for isotopic analysis. The key isotopes are those of oxygen and carbon. At the PTB, there is a dramatic shift in oxygen isotope values of marine carbonates, a decrease in the value of the δ18O ratio of about six parts per thousand (ppt), corresponding to a global temperature rise of about 6oC. Climate modellers have shown how global warming can reduce ocean circulation and the amount of dissolved oxygen, creating anoxia in the oceans; this is seen in marine sediments from around the world. The marine evidence for anoxia nearly world-wide is dramatic and convincing, and this episode of superanoxia, which surely killed much of the life on the sea bottom (Wignall & Twitchett, 1996), must form part of any model for events at the PTB.
Carbon isotopes have been hugely important in determining models for the PT mass extinction. Geochemists measure the ratio of the stable isotopes 13C and 12C in limestones and fossil shells, and even in carbonate palaeosols. In nature, most carbon occurs as 12C, with minor, but measurable, amounts of 13C. The ratio of these two isotopes in the atmosphere is the same as in the surface waters of the oceans. During photosynthesis, plants preferentially take up 12C to produce organic matter. If this organic matter is buried, rather than returned to the atmosphere-ocean system, then the atmosphere-ocean 13C: 12C ratio will shift in favour of the heavier isotope. Conventionally, this ratio is expressed as δ13C, which is the difference between the 13C: 12C ratios in the sample being tested and in a known standard.

In the ocean system, during times of high surface productivity, large amounts of organic matter are fixed at the surface and the surface waters of the ocean become (relatively) enriched in 13C. Shallow-water carbonate deposits are precipitated from this seawater, and record the seawater 13C: 12C ratio without any preferential uptake of one or other isotope. Therefore, during times of high surface productivity, shallow water carbonates record a positive shift in δ13C (i.e. towards the heavier isotope).

The PTB is characterized by a negative shift in δ13C, which is recorded in the carbonate deposits of all geological sections studied so far (e.g. Magaritz et al. 1988; Sephton et al., 2002), including terrestrial ones (Retallack 1995; MacLeod et al. 2000). On the face of it, this should imply a massive decrease in biological production and rate of burial of organic matter.

 

[Old Rocks]

Palaeobiology and Biodiversity Research Group, Department of Earth Sciences, University of Bristol

Independently, Roger Smith - a sedimentologist working in South Africa - and his collaborator Peter Ward from the University of Washington in Seattle, had reached a similar conclusion. The famous Permo-Triassic succession of the Karoo Basin showed a similar sedimentary switch from a low-energy flow regime with meandering streams in the Late Permian to a high-energy flow regime with braided streams and alluvial fans in the Early Triassic (Ward et al. 2000).

Since then, a similar shift in fluvial style has been noted across the PTB in Australia (Michaelsen 2002), India (Sarkar et al. 2003) and Spain (Arche & López-Gómez, 2005). Such a shift does not occur everywhere: in numerous PT sections in Antarctica, for example, there is some evidence of coarsening of the sandstones above the boundary in some sections, but braided streams set in during the latest Permian, and the main change is from sandstones dominated by volcanic clasts in the Permian to sandstones with quartz clasts in the earliest Triassic (Collinson et al. 2006).

Studies of soils and their chemical signatures (Retallack 2005; Sephton et al. 2005) confirm that there was a soil erosion crisis, where soil and organic matter from the land was washed into the sea. If this was a world-wide phenomenon, local-scale tectonism cannot be the cause - but what then?

Perhaps there were global-scale upheavals, with mountains being uplifted in several parts of the world. So far, independent evidence for such global activity has not been found. Perhaps there was a massive increase in rainfall world-wide? Again, there is no clear evidence for such a phenomenon, nor a suggestion of how it might have come about. If anything, the evidence suggests reduced rainfall.

Andy Newell (Newell et al 1999) argued that the abrupt increase in channel size associated with a major influx of gravel around the PTB could be related to climate change. There was a well-documented switch worldwide from a semi-arid/sub-humid climate in the latest Permian toward one of greater aridity in the earliest Triassic, and this can increase sediment yield by reducing vegetation cover. If vegetation is stripped from the surface of the land, rates of erosion can increase perhaps tenfold.

This fits with other evidence that the normal green plants had been temporarily killed off and replaced by an unusual horizon at the boundary, dominated by strands produced either by fungi or algae. Below this horizon, the sediment samples contain spores of ferns, seedferns, horsetails and other plants that grew at low, medium and tree-like levels. Such plants soon return in higher units in the Early Triassic. But the fungal/ algal boundary bed perhaps indicates a dramatic loss of normal vegetation. We know the devastating erosion that can follow the removal of plants today, such as in Bangladesh, where the rate of runoff and erosion has increased hugely after logging higher in the foothills of the Himalayas.

 

[Old Rocks]

Palaeobiology and Biodiversity Research Group, Department of Earth Sciences, University of Bristol

This was a rich and complex ecosystem, with as many animals as in any modern terrestrial community. There were herbivores specializing in plants of different kinds, fish-eating amphibians, insect-eating synapsids, carnivores feeding on small prey, and the gorgonopsians, so-called top predators, feeding on the largest of the herbivores. These animals were all wiped out by the end-Permian crisis.
The amphibians and reptiles that survived the crisis into the earliest Triassic in Russia are a poor assemblage, the so-called Lower Vetluga (Vokhmian) Community. The only reasonably sized herbivore was Lystrosaurus; other tetrapods include one species of procolophonid, and some rare therocephalians and diapsids that fed on insects and smaller reptiles, as well as fish-eating, broad-headed amphibians.

The massive volcanic eruptions in Siberia, which may have happened in pulses over half a million years, pumped out carbon dioxide and other gases that caused massive acid rain and global warming. The acid rain killed the plants, and as the plants died and their roots shrivelled, the soil was exposed, and normal rainfall caused massive erosion of soil and plants into the rivers and seas. Perhaps the only primary producers left on land were fungi or algae.

 

[Old Rocks]

Westwall, I have found no mention of glaciation in the site that you posted. A rather nice site, by the way, Thank You.

What I have seen there is mention of a 6 C rise in temperatures globally, a massive climate change indictated by the change from meandering silted river channels, to braided channels with boulder far from the mountain sources of those boulders. Perhaps you would care to post where in that site there is a mention of glaciers during the extinction period?

 

[Old Rocks]

Permian : The Marine Realm and The End-Permian Extinction

Several factors have been implicated in this massive extinction. The formation of Pangea reduced the continental shelves, decreasing the area available for shallow-water organisms. Rapid warming and glaciation both occurred during the Permian as well. These events do not seem to have happened at the same time as the extinction event, however. Indeed, a first extinction pulse actually occurred during the Middle Permian and may have been caused by a dramatic drop in sea level. A more likely cause for the end-Permian extinction was a series of volcanic eruptions in Siberia, which produced massive outpourings of lava called flood basalts. This volcanism covered an area about two-thirds the size of the United States and erupted very rapidly just at the time of the extinction. It may have caused significant atmospheric disturbances, global warming, and anoxic (low-oxygen) ocean waters. The other possible cause is the impact of a large extraterrestrial object, as occurred with the extinction at the end of the Cretaceous. Direct evidence for such an impact is sparse, but the available data are consistent with such a cause.

While there was glaciation in the Permian, it seems to have been millions of years prior to the PT event.

 

[Old Rocks]

Volcanism, mass extinction, and carbon isotope fluctuations in the Middle Permian of China | Jason R Ali - Academia.edu

The close temporal link between the onset of eruptions and extinction suggests a cause-and-effect scenario. Cooling and acid rain (caused by SO2 effusion and sulfate aerosol formation)and consequent environmental deterioration are candidates for this link ( 18, 19). The dominance of pyroclastic volcanism (rather than more quiescent-style flood basalt eruptions) in the initial eruptive stages of the Emeishan province and the large scale of the flows (30 to 200 m thick)suggest that such effects are likely to have been severe. The subsequent negative shift of C isotope values is too large to be attributed to relatively heavy volcanic CO2 (d 13 C =– 5&#8240, but it may record the release of much lighter thermogenic C from the site of volcanism (20).This was in the aftermath of the biotic crisis, but the high diversity of the post-extinction biota suggests that the light C flux is not linked to any prolongation of the environmental stress that caused the extinction.Our study of the volcano-sedimentary recordof southwest China reveals that the Middle Permian marine crisis precisely coincided with the onset of Emeishan volcanism. This provides evidence for a potential link between mass ex-tinction and the eruption of this igneous province, although the absolute time scale for the event is not yet known. The subsequent negative d 13C excursion implies that the C cycle was destabilized for some time after the extinctions, perhaps by C release from thermogenic sources.

 

[Old Rocks]

So there is a mid-Permian extinction event linked to the emplacement of GHGs in the atmosphere, and a subsequent rapid warming, from volcanism. Seems that there is ample evidence that warming does cause extinction events, the same as rapid cooling also causes extinction events. And now the rapid warming we are experiancing is the result of the emplacement of GHGs in the atmosphere as a result of human activities. And the physics of the matter does not care whether volcanos or biological species put the GHGs there, the result will be the same.

 

[Kosh]

So there is a mid-Permian extinction event linked to the emplacement of GHGs in the atmosphere, and a subsequent rapid warming, from volcanism. Seems that there is ample evidence that warming does cause extinction events, the same as rapid cooling also causes extinction events. And now the rapid warming we are experiancing is the result of the emplacement of GHGs in the atmosphere as a result of human activities. And the physics of the matter does not care whether volcanos or biological species put the GHGs there, the result will be the same.

So basically you posted all those links and still didn't understand what you posted and thus show that the AGW church propaganda rules over science.

 

[editec]

The fact remains that ALL empirical evidence shows that CO2 lags temperature by hundreds of years.

If conditions in the present are different, the present will not act like the past.

For some reason, that very basic logic is something denialists have never been capable of grasping. That's the main reason why they're laughed at in the world of science. Scientists are good at logic, so they instantly recognize how awful the logic of the denialists is.

Incorrect. The present Always follows the past. Always has, and always will. That's what physics does for you. Physical laws are immutable. They MUST react the same. Put another way, the same CO2 is on this planet as was here when it was created. NOTHING has been added.

You are a tragically misinformed person, WESTWALL

 

[JimBowie1958]

Phd geologist? The proxies indicate strong rise in GHGs before both the PT event and the Tertiary event.

The Permian-Triassic Extinction - Volcanism and the Great Dying

Consider the stressed biosphere late in the Permian: low oxygen levels restricted land life to low elevations. Ocean circulation was sluggish, raising the risk of anoxia. And the continents sat in a single mass (Pangea) with a reduced diversity of habitats. Then great eruptions begin in what is Siberia today, starting the largest of Earth's large igneous provinces (LIPs).

These eruptions release huge amounts of carbon dioxide (CO2) and sulfur gases (SOx). In the short term the SOx cools the Earth while in the longer term the CO2 warms it. The SOx also creates acid rain while CO2 entering the seawater makes it harder for calcified species to build shells. Other volcanic gases destroy the ozone layer. And finally, magma rising through coal beds releases methane, another greenhouse gas.

With all of this happening to a vulnerable world, most life on Earth could not survive. Luckily it has never been quite this bad since then. But global warming poses some of the same threats today

I prefer this discussion on the extinction event. It has no internal bias. Climate change is addressed and cold comes out as a possible cause by a margin of four to one against warming as a cause. Further the largest sea level drop ever recorded occurred at the end of the Permian further reinforcing the theory that it was glaciation that was a proximal cause of extinction.


Palaeobiology and Biodiversity Research Group, Department of Earth Sciences, University of Bristol

Palaeobiology and Biodiversity Research Group, Department of Earth Sciences, University of Bristol


Isotopes and climate
Isotopes across the PTB and climate change

A major objective on the 2004 expedition was to take samples for isotopic analysis. The key isotopes are those of oxygen and carbon. At the PTB, there is a dramatic shift in oxygen isotope values of marine carbonates, a decrease in the value of the δ18O ratio of about six parts per thousand (ppt), corresponding to a global temperature rise of about 6oC. Climate modellers have shown how global warming can reduce ocean circulation and the amount of dissolved oxygen, creating anoxia in the oceans; this is seen in marine sediments from around the world. The marine evidence for anoxia nearly world-wide is dramatic and convincing, and this episode of superanoxia, which surely killed much of the life on the sea bottom (Wignall & Twitchett, 1996), must form part of any model for events at the PTB.
Carbon isotopes have been hugely important in determining models for the PT mass extinction. Geochemists measure the ratio of the stable isotopes 13C and 12C in limestones and fossil shells, and even in carbonate palaeosols. In nature, most carbon occurs as 12C, with minor, but measurable, amounts of 13C. The ratio of these two isotopes in the atmosphere is the same as in the surface waters of the oceans. During photosynthesis, plants preferentially take up 12C to produce organic matter. If this organic matter is buried, rather than returned to the atmosphere-ocean system, then the atmosphere-ocean 13C: 12C ratio will shift in favour of the heavier isotope. Conventionally, this ratio is expressed as δ13C, which is the difference between the 13C: 12C ratios in the sample being tested and in a known standard.

In the ocean system, during times of high surface productivity, large amounts of organic matter are fixed at the surface and the surface waters of the ocean become (relatively) enriched in 13C. Shallow-water carbonate deposits are precipitated from this seawater, and record the seawater 13C: 12C ratio without any preferential uptake of one or other isotope. Therefore, during times of high surface productivity, shallow water carbonates record a positive shift in δ13C (i.e. towards the heavier isotope).

The PTB is characterized by a negative shift in δ13C, which is recorded in the carbonate deposits of all geological sections studied so far (e.g. Magaritz et al. 1988; Sephton et al., 2002), including terrestrial ones (Retallack 1995; MacLeod et al. 2000). On the face of it, this should imply a massive decrease in biological production and rate of burial of organic matter.

Not that I agree with you, but it is nice to see you being rational on those rare days you feel up to it.

Hope you have more such days.