Lets be honest about the ice melt season

[Old Rocks]

Extinction and Climate « ClimateSight

In the late Permian, a huge expanse of active volcanoes existed in what is now Siberia. They covered 4 million square kilometres, which is fifteen times the area of modern-day Britain (White, 2002). Over the years, these volcanoes pumped out massive quantities of carbon dioxide, increasing the average temperature of the planet. However, as the warming continued, a positive feedback kicked in: ice and permafrost melted, releasing methane that was previously safely frozen in. Methane is a far stronger greenhouse gas than carbon dioxide – over 100 years, it traps approximately 21 times more heat per molecule (IPCC AR4). Consequently, the warming became much more severe.

When the planet warms a lot in a relatively short period of time, a particularly nasty condition can develop in the oceans, known as anoxia. Since the polar regions warm more than the equator, the temperature difference between latitudes decreases. As global ocean circulation is driven by this temperature difference, ocean currents weaken significantly and the water becomes relatively stagnant. Without ocean turnover, oxygen doesn’t get mixed in – and it doesn’t help that warmer water can hold less oxygen to begin with. As a result of this oxygen depletion, bacteria in the ocean begins to produce hydrogen sulfide (H2S). That’s what makes rotten eggs smell bad, and it’s actually poisonous in large enough quantities. So if an organism wasn’t killed off by abrupt global warming, and was able to survive without much oxygen in the ocean (or didn’t live in the ocean at all), it would probably soon be poisoned by the hydrogen sulfide being formed in the oceans and eventually released into the atmosphere.

The Permian-Triassic extinction wasn’t the only time anoxia developed. It may have been a factor in the Late Triassic extinction, as well as smaller extinctions between the Big Five. Overall, it’s one reason why a warm planet tends to be less favourable to life than a cold one, as a 2008 study in the UK showed. The researchers examined 520 million years of data on fossils and temperature reconstructions, which encompasses almost the entire history of multicellular life on Earth. They found that high global temperatures were correlated with low levels of biodiversity (the number of species on Earth) and high levels of extinction, while cooler periods enjoyed high biodiversity and low extinction

 

[gslack]

Extinction and Climate « ClimateSight

In the late Permian, a huge expanse of active volcanoes existed in what is now Siberia. They covered 4 million square kilometres, which is fifteen times the area of modern-day Britain (White, 2002). Over the years, these volcanoes pumped out massive quantities of carbon dioxide, increasing the average temperature of the planet. However, as the warming continued, a positive feedback kicked in: ice and permafrost melted, releasing methane that was previously safely frozen in. Methane is a far stronger greenhouse gas than carbon dioxide – over 100 years, it traps approximately 21 times more heat per molecule (IPCC AR4). Consequently, the warming became much more severe.

When the planet warms a lot in a relatively short period of time, a particularly nasty condition can develop in the oceans, known as anoxia. Since the polar regions warm more than the equator, the temperature difference between latitudes decreases. As global ocean circulation is driven by this temperature difference, ocean currents weaken significantly and the water becomes relatively stagnant. Without ocean turnover, oxygen doesn’t get mixed in – and it doesn’t help that warmer water can hold less oxygen to begin with. As a result of this oxygen depletion, bacteria in the ocean begins to produce hydrogen sulfide (H2S). That’s what makes rotten eggs smell bad, and it’s actually poisonous in large enough quantities. So if an organism wasn’t killed off by abrupt global warming, and was able to survive without much oxygen in the ocean (or didn’t live in the ocean at all), it would probably soon be poisoned by the hydrogen sulfide being formed in the oceans and eventually released into the atmosphere.

The Permian-Triassic extinction wasn’t the only time anoxia developed. It may have been a factor in the Late Triassic extinction, as well as smaller extinctions between the Big Five. Overall, it’s one reason why a warm planet tends to be less favourable to life than a cold one, as a 2008 study in the UK showed. The researchers examined 520 million years of data on fossils and temperature reconstructions, which encompasses almost the entire history of multicellular life on Earth. They found that high global temperatures were correlated with low levels of biodiversity (the number of species on Earth) and high levels of extinction, while cooler periods enjoyed high biodiversity and low extinction

Oh yes! the dreaded blog angle... Seriously oldsocks... Its a random web blog... Why not just say you went google happy and pulled this out of your butt....

 

[westwall]

Extinction and Climate « ClimateSight

In the late Permian, a huge expanse of active volcanoes existed in what is now Siberia. They covered 4 million square kilometres, which is fifteen times the area of modern-day Britain (White, 2002). Over the years, these volcanoes pumped out massive quantities of carbon dioxide, increasing the average temperature of the planet. However, as the warming continued, a positive feedback kicked in: ice and permafrost melted, releasing methane that was previously safely frozen in. Methane is a far stronger greenhouse gas than carbon dioxide – over 100 years, it traps approximately 21 times more heat per molecule (IPCC AR4). Consequently, the warming became much more severe.

When the planet warms a lot in a relatively short period of time, a particularly nasty condition can develop in the oceans, known as anoxia. Since the polar regions warm more than the equator, the temperature difference between latitudes decreases. As global ocean circulation is driven by this temperature difference, ocean currents weaken significantly and the water becomes relatively stagnant. Without ocean turnover, oxygen doesn’t get mixed in – and it doesn’t help that warmer water can hold less oxygen to begin with. As a result of this oxygen depletion, bacteria in the ocean begins to produce hydrogen sulfide (H2S). That’s what makes rotten eggs smell bad, and it’s actually poisonous in large enough quantities. So if an organism wasn’t killed off by abrupt global warming, and was able to survive without much oxygen in the ocean (or didn’t live in the ocean at all), it would probably soon be poisoned by the hydrogen sulfide being formed in the oceans and eventually released into the atmosphere.

The Permian-Triassic extinction wasn’t the only time anoxia developed. It may have been a factor in the Late Triassic extinction, as well as smaller extinctions between the Big Five. Overall, it’s one reason why a warm planet tends to be less favourable to life than a cold one, as a 2008 study in the UK showed. The researchers examined 520 million years of data on fossils and temperature reconstructions, which encompasses almost the entire history of multicellular life on Earth. They found that high global temperatures were correlated with low levels of biodiversity (the number of species on Earth) and high levels of extinction, while cooler periods enjoyed high biodiversity and low extinction

Seriously? A students blog...really? Let's look at her opening statement..

"Life on Earth does not enjoy change, and climate change is something it likes least of all."

A more ludicrous statement from a student I have never heard. The planet THRIVES on change. Take a look at the fossil record sometime. Notice how it keeps getting more diverse? That's called change.

Here is the best general overview of the various theories that have been presented for the Great Dying. Please note there are many candidates for the cause. Please also note that COLD is the dominant climatic suspect for the cause.

Your dear blogger focuses on CO2 from the Siberian Traps but ignores the sulfer dioxide and particulate matter that would have cooled the atmosphere far more thouroughly then the CO2 could ever hope to raise the temps.

But then what do you expect from an "aspiring climatologist".



"Explanatory theories

Many theories have been presented for the cause of the extinction, including plate tectonics, an impact event, a supernova, extreme volcanism, and the release of frozen methane hydrate from the ocean beds to cause a greenhouse effect, or some combination of factors.

Map of Pangaea
Plate tectonics. At the time of the Permian extinction, all the continents had recently joined to form the super-continent Pangaea and the super-ocean Panthalassa. This configuration radically decreased the extent and range of shallow aquatic environments and exposed formerly isolated organisms of the rich continental shelves to competition from invaders. As the planet's epicontinental systems coalesced, many marine ecosystems, especially ones that evolved in isolation, would not have survived those changes. Pangaea's formation would have altered both oceanic circulation and atmospheric weather patterns, creating seasonal monsoons. Pangaea seems to have formed millions of years before the great extinction, however, and very gradual changes like continental drift alone probably could not cause the sudden, simultaneous destruction of both terrestrial and oceanic life.

Impact event. When large bolides (asteroids or comets) impact Earth, the aftermath weakens or kills much of the life that thrived previously. Release of debris and carbon dioxide into the atmosphere reduces the productivity of life and causes both global warming and ozone depletion. Evidence of increased levels of atmospheric carbon dioxide exists in the fossil record. Material from the Earth's mantle released during volcanic eruption has also been shown to contain iridium, an element associated with meteorites. At present, there is only limited and disputed evidence of iridium and shocked quartz occurring with the Permian event, though such evidence has been very abundantly associated with an impact origin for the Cretaceous-Tertiary extinction event. If an extraterrestrial impact triggered the Permian extinction event, scientists ask, where is the impact crater? Part of the answer may lie in the fact that there is no Permian-age oceanic crust remaining; all of it has been subducted, so plate tectonics during the last 252 million years have erased any possible P-T seafloor crater. Others have claimed evidence of a possible impact site off the coast of present-day Australia.

Supernova. A supernova occurring within ten parsecs (33 light years) of Earth would produce enough gamma radiation to destroy the ozone layer for several years. The resulting direct ultraviolet radiation from the sun would weaken or kill nearly all existing species. Only those deep in the oceans would be unaffected. Statistical frequency of supernovas suggests that one at the P-T boundary would not be unlikely. A gamma ray burst (the most energetic explosions in the universe, believed to be caused by a very massive supernova or two objects as dense as neutron stars colliding) that occurred within approximately 6,000 light years would produce the same effect.

Volcanism. The P-T boundary was marked with many volcanic eruptions. In the Siberian Traps, now a sub-Arctic wilderness, over 200,000 square kilometers were covered in torrents of lava. The Siberian flood basalt eruption, the biggest volcanic effect on Earth, lasted for millions of years. The acid rain, brief initial global cooling with each of the bursts of volcanism, followed by longer-term global warming from released volcanic gases, and other weather effects associated with enormous eruptions could have globally threatened life. The theory is debated whether volcanic activity, over such a long time, could alter the climate enough to kill off 95 percent of life on Earth. There is evidence for this theory though. Fluctuations in air and water temperature are evident in the fossil record, and the uranium/thorium ratios of late Permian sediments indicate that the oceans were severely anoxic around the time of the extinction. Numerous indicators of volcanic activity at the P-T boundary are present, though they are similar to bolide impact indicators, including iridium deposits. The volcanism theory has the advantage over the bolide theory, though, in that it is certain that an eruption of the Siberian Traps—the largest known eruption in the history of Earth—occurred at this time, while no direct evidence of bolide impact has been located.

Atmospheric hydrogen sulfide buildup. In 2005, geoscientist Dr. Lee R. Kump published a theory explaining a cascade of events leading to the Great Extinction. Several massive volcanic eruptions in Siberian Traps, described above, started a warming of the atmosphere. The warming itself did not seem to be large enough to cause such a massive extinction event. However, it could have interfered with the ocean flow. Cold water at the poles dissolves atmospheric oxygen, cools even more, and sinks to the bottom, slowly moving to the equator, carrying the dissolved oxygen. The warmer the water is, the less oxygen it can dissolve and the slower it circulates. The resulting lack of supply of dissolved oxygen would lead to depletion of aerobic marine life. The oceans would then become a realm of bacteria metabolizing sulfates, and producing hydrogen sulfide, which would then get released into the water and the atmosphere, killing oceanic plants and terrestrial life. Once such process gets underway, the atmosphere turns into a mix of methane and hydrogen sulfide. Terrestrial plants thrive on carbon dioxide, while hydrogen sulfide kills them. Increase of concentration of carbon dioxide would not cause extinction of plants, but according to the fossils, plants were massively affected as well. Hydrogen sulfide also damages the ozone layer, and fossil spores from the end-Permian era show deformities that could have been caused by ultraviolet radiation.

Methane hydrate gasification. In 2002, a documentary, The Day the Earth Nearly Died, summarized some recent findings and speculation concerning the Permian extinction event. Paul Wignall examined Permian strata in Greenland, where the rock layers devoid of marine life are tens of meters thick. With such an expanded scale, he could judge the timing of deposition more accurately and ascertained that the entire extinction lasted merely 80,000 years and showed three distinctive phases in the plant and animal fossils they contained. The extinction appeared to kill land and marine life selectively at different times. Two periods of extinctions of terrestrial life were separated by a brief, sharp, almost total extinction of marine life. Such a process seemed too long, however, to be accounted for by a meteorite strike. His best clue was the carbon isotope balance in the rock, which showed an increase in carbon-12 over time. The standard explanation for such a spike—rotting vegetation—seemed insufficient. Geologist Gerry Dickens suggested that the increased carbon-12 could have been rapidly released by the upwelling of frozen methane hydrate from the seabed. Experiments to assess how large a rise in deep sea temperature would be required to sublimate solid methane hydrate suggested that a rise of 5°C would be sufficient. Released from the pressures of the ocean depths, methane hydrate expands to create huge volumes of methane gas, one of the most powerful of the greenhouse gases. The resulting additional 5°C rise in average temperatures would have been sufficient to kill off most of the life on earth.

A combination. The Permian extinction is unequaled; it is obviously not easy to destroy almost all life on Earth. The difficulty in imagining a single cause of such an event has led to an explanation humorously termed the "Murder on the Orient Express" theory: they all did it. A combination involving some or all of the following is postulated: Continental drift created a non-fatal but precariously balanced global environment, a supernova weakened the ozone layer, and then a large meteor impact triggered the eruption of the Siberian Traps. The resultant global warming eventually was enough to melt the methane hydrate deposits on continental shelves of the world-ocean."



Mass extinction - New World Encyclopedia

 

[Old Rocks]

Volcanoes Ignite Coal Fires that Caused the Permian Extinction

Coal Fires Ignited by Volcanoes May Have Caused the Permian Extinction
An extinction of 95% of marine species and 70% of land species
Republished from a January, 2011 press release by Leanne Yohemas of the University of Calgary.

Massive Volcanic Eruption Ignites Coal Seams

About 250 million years ago, about 95 percent of life was wiped out in the sea and 70 percent on land. Researchers at the University of Calgary believe they have discovered evidence to support massive volcanic eruptions burnt significant volumes of coal, producing ash clouds that had broad impact on global oceans.

"This could literally be the smoking gun that explains the latest Permian extinction," says Dr. Steve Grasby, adjunct professor in the U of C's geoscience department and research scientist at Natural Resources Canada.

Grasby and colleagues discovered layers of coal ash in rocks from the extinction boundary in Canada's High Arctic that give the first direct proof to support this and have published their findings in Nature Geoscience.
........................................................................................................

Emissions Similar to Coal-Fired Power Plants


"We saw layers with abundant organic matter and Hamed immediately determined that they were layers of coal-ash, exactly like that produced by modern coal burning power plants," says Beauchamp.

Sanei adds: "Our discovery provides the first direct confirmation for coal ash during this extinction as it may not have been recognized before."

 

[Old Rocks]

Coal-fired trigger of mass extinction : Nature News

The magma went through a juicy bit of crust that it can release a lot of nasty things from," says Paul Wignall, a palaeontologist at the University of Leeds, UK, who studies mass extinction events.


Once the mixture hit the oxygen-laden air, huge clouds of gas and fly ash mushroomed into the stratosphere. The black clouds caught the westerly winds and ash rained down on the Buchanan Lake in the Sverdrup Basin of the Arctic, where Grasby and his team found their samples. This happened three times over a period of 500,000 to 750,000. The final fly-ash layer found by the team was laid down just before the extinction event.

This may have been the tipping point, says Wignall. Studies have suggested the volcanoes released 3 trillion tonnes of carbon, enough to trigger massive climate change. The eruptions also caused acid rain and emitted sufficient halogens to create an ozone hole, he says. Toxic fly ash, on top of all this, may have been the final blow.

"I can't suggest that this is the answer to the mass extinction story, but it is a new component to it," he says. "It is like throwing the kitchen sink at the world."

 

[westwall]

Volcanoes Ignite Coal Fires that Caused the Permian Extinction

Coal Fires Ignited by Volcanoes May Have Caused the Permian Extinction
An extinction of 95% of marine species and 70% of land species
Republished from a January, 2011 press release by Leanne Yohemas of the University of Calgary.

Massive Volcanic Eruption Ignites Coal Seams

About 250 million years ago, about 95 percent of life was wiped out in the sea and 70 percent on land. Researchers at the University of Calgary believe they have discovered evidence to support massive volcanic eruptions burnt significant volumes of coal, producing ash clouds that had broad impact on global oceans.

"This could literally be the smoking gun that explains the latest Permian extinction," says Dr. Steve Grasby, adjunct professor in the U of C's geoscience department and research scientist at Natural Resources Canada.

Grasby and colleagues discovered layers of coal ash in rocks from the extinction boundary in Canada's High Arctic that give the first direct proof to support this and have published their findings in Nature Geoscience.
........................................................................................................

Emissions Similar to Coal-Fired Power Plants


"We saw layers with abundant organic matter and Hamed immediately determined that they were layers of coal-ash, exactly like that produced by modern coal burning power plants," says Beauchamp.

Sanei adds: "Our discovery provides the first direct confirmation for coal ash during this extinction as it may not have been recognized before."

SO2 would have far greater impact then the CO2 especially as it is found CO2 has little to no impact on temps. It's sad how far science has fallen in the ever greater quest for a buck.

 

[Old Rocks]

The Permian-Triassic Extinction - Volcanism and the Great Dying

The Volcanic Scenario

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.

 

[Old Rocks]

Volcanoes Ignite Coal Fires that Caused the Permian Extinction

Coal Fires Ignited by Volcanoes May Have Caused the Permian Extinction
An extinction of 95% of marine species and 70% of land species
Republished from a January, 2011 press release by Leanne Yohemas of the University of Calgary.

Massive Volcanic Eruption Ignites Coal Seams

About 250 million years ago, about 95 percent of life was wiped out in the sea and 70 percent on land. Researchers at the University of Calgary believe they have discovered evidence to support massive volcanic eruptions burnt significant volumes of coal, producing ash clouds that had broad impact on global oceans.

"This could literally be the smoking gun that explains the latest Permian extinction," says Dr. Steve Grasby, adjunct professor in the U of C's geoscience department and research scientist at Natural Resources Canada.

Grasby and colleagues discovered layers of coal ash in rocks from the extinction boundary in Canada's High Arctic that give the first direct proof to support this and have published their findings in Nature Geoscience.
........................................................................................................

Emissions Similar to Coal-Fired Power Plants


"We saw layers with abundant organic matter and Hamed immediately determined that they were layers of coal-ash, exactly like that produced by modern coal burning power plants," says Beauchamp.

Sanei adds: "Our discovery provides the first direct confirmation for coal ash during this extinction as it may not have been recognized before."

SO2 would have far greater impact then the CO2 especially as it is found CO2 has little to no impact on temps. It's sad how far science has fallen in the ever greater quest for a buck.

Silly ass. SO2 has a cooling effect. CO2 has a warming effect. And SO2 soon rains out of the atmosphere, whereas CO2 stays there for hundreds of years. Not only that, this is what the record shows. There is evidence of both glaciation, extreme warming, a very violent weather in a short period of time, geologically. That fits the scenerio with coal fires, and Siberia was not the only place this was happening.

Permian
See also: Anoxic event
There is evidence that the oceans became anoxic (severely deficient in oxygen) towards the end of the Permian. There was a noticeable and rapid onset of anoxic deposition in marine sediments around East Greenland near the end of the Permian.[109] The uranium/thorium ratios of several late Permian sediments indicate that the oceans were severely anoxic around the time of the extinction.[110]

This would have been devastating for marine life, producing widespread die-offs except for anaerobic bacteria inhabiting the sea-bottom mud. There is also evidence that anoxic events can cause catastrophic hydrogen sulfide emissions from the sea floor (see below).

The sequence of events leading to anoxic oceans might have involved a period of global warming that reduced the temperature gradient between the equator and the poles, which slowed or even stopped the thermohaline circulation. The slow-down or stoppage of the thermohaline circulation could have reduced the mixing of oxygen in the ocean.[110]

However, one research article suggests that the types of oceanic thermohaline circulation that may have existed at the end of the Permian are not likely to have supported deep-sea anoxia.[111]

[edit] Hydrogen sulfide emissions

A severe anoxic event at the end of the Permian could have made sulfate-reducing bacteria the dominant force in oceanic ecosystems, causing vast emissions of hydrogen sulfide that poisoned plant and animal life on both land and sea, as well as severely weakening the ozone layer, exposing much of the life that remained to fatal levels of UV radiation.[112] Indeed, anaerobic photosynthesis by Chlorobiaceae (green sulfur bacteria), and its accompanying hydrogen sulfide emissions, occurred from the end-Permian into the early Triassic. The fact that this anaerobic photosynthesis persisted into the early Triassic is consistent with fossil evidence that the recovery from the Permian–Triassic extinction was remarkably slow.[113]

This theory has the advantage of explaining the mass extinction of plants, which ought otherwise to have thrived in an atmosphere with a high level of carbon dioxide. Fossil spores from the end-Permian further support the theory: many show deformities that could have been caused by ultraviolet radiation, which would have been more intense after hydrogen sulfide emissions weakened the ozone layer.

 

[gslack]

Thats it oldsocks spam it until no one remembers you cited a students blog as evidence.... HAHAHHHAHAHAAAA!

 

[westwall]

Volcanoes Ignite Coal Fires that Caused the Permian Extinction

Coal Fires Ignited by Volcanoes May Have Caused the Permian Extinction
An extinction of 95% of marine species and 70% of land species
Republished from a January, 2011 press release by Leanne Yohemas of the University of Calgary.

Massive Volcanic Eruption Ignites Coal Seams

About 250 million years ago, about 95 percent of life was wiped out in the sea and 70 percent on land. Researchers at the University of Calgary believe they have discovered evidence to support massive volcanic eruptions burnt significant volumes of coal, producing ash clouds that had broad impact on global oceans.

"This could literally be the smoking gun that explains the latest Permian extinction," says Dr. Steve Grasby, adjunct professor in the U of C's geoscience department and research scientist at Natural Resources Canada.

Grasby and colleagues discovered layers of coal ash in rocks from the extinction boundary in Canada's High Arctic that give the first direct proof to support this and have published their findings in Nature Geoscience.
........................................................................................................

Emissions Similar to Coal-Fired Power Plants


"We saw layers with abundant organic matter and Hamed immediately determined that they were layers of coal-ash, exactly like that produced by modern coal burning power plants," says Beauchamp.

Sanei adds: "Our discovery provides the first direct confirmation for coal ash during this extinction as it may not have been recognized before."

SO2 would have far greater impact then the CO2 especially as it is found CO2 has little to no impact on temps. It's sad how far science has fallen in the ever greater quest for a buck.

Silly ass. SO2 has a cooling effect. CO2 has a warming effect. And SO2 soon rains out of the atmosphere, whereas CO2 stays there for hundreds of years. Not only that, this is what the record shows. There is evidence of both glaciation, extreme warming, a very violent weather in a short period of time, geologically. That fits the scenerio with coal fires, and Siberia was not the only place this was happening.

Permian
See also: Anoxic event
There is evidence that the oceans became anoxic (severely deficient in oxygen) towards the end of the Permian. There was a noticeable and rapid onset of anoxic deposition in marine sediments around East Greenland near the end of the Permian.[109] The uranium/thorium ratios of several late Permian sediments indicate that the oceans were severely anoxic around the time of the extinction.[110]

This would have been devastating for marine life, producing widespread die-offs except for anaerobic bacteria inhabiting the sea-bottom mud. There is also evidence that anoxic events can cause catastrophic hydrogen sulfide emissions from the sea floor (see below).

The sequence of events leading to anoxic oceans might have involved a period of global warming that reduced the temperature gradient between the equator and the poles, which slowed or even stopped the thermohaline circulation. The slow-down or stoppage of the thermohaline circulation could have reduced the mixing of oxygen in the ocean.[110]

However, one research article suggests that the types of oceanic thermohaline circulation that may have existed at the end of the Permian are not likely to have supported deep-sea anoxia.[111]

[edit] Hydrogen sulfide emissions

A severe anoxic event at the end of the Permian could have made sulfate-reducing bacteria the dominant force in oceanic ecosystems, causing vast emissions of hydrogen sulfide that poisoned plant and animal life on both land and sea, as well as severely weakening the ozone layer, exposing much of the life that remained to fatal levels of UV radiation.[112] Indeed, anaerobic photosynthesis by Chlorobiaceae (green sulfur bacteria), and its accompanying hydrogen sulfide emissions, occurred from the end-Permian into the early Triassic. The fact that this anaerobic photosynthesis persisted into the early Triassic is consistent with fossil evidence that the recovery from the Permian–Triassic extinction was remarkably slow.[113]

This theory has the advantage of explaining the mass extinction of plants, which ought otherwise to have thrived in an atmosphere with a high level of carbon dioxide. Fossil spores from the end-Permian further support the theory: many show deformities that could have been caused by ultraviolet radiation, which would have been more intense after hydrogen sulfide emissions weakened the ozone layer.

Uhhhh DUH Cooling has been proven to kill things. Warmth has never been proven to kill things. Quite the opposite in point of fact. The dinosaurs lived when the planet was extremely warm and they had plenty of forage to keep them fed. Look wherever you care to and you will see that when it was cold things died like mad. The only things that have died in warm times are in your fevered imaginations.

Nice try. Try reading some history. The "theories" you worship are crap with no empirical data to support them.

 

[bripat9643]

Got supporting evidence for this assertion?

I've seen nothing indicative that turn of the first millenia 800-1200 AD was any warmer than current temperatures.

The Vikings grazed cattle and sheep there in 800-1200 AD.

Doesn't mean it was balmy. That's totally ludicrous.

ROFL! It means it was a lot warmer than it is now. Do you imagine anyone could make a living as a farmer in Greenland now?

 

[bripat9643]

Doesn't mean it was balmy. That's totally ludicrous.

All "balmy" means is pleasantly warm.

It was balmy enough to graze cattle.

Balmy means NOTHING. Tell us what the temps were compared to today.

They were warmer than today based on the vegatation and fauna the environment supported.

Unlike AGW quack scientists, I don't presume to have an exact number for the temperature based on the size of a tree ring on a tree growing on a mountain top 6000 miles away.

 

[bripat9643]

LOLOL....you are such a fraud, walleyed. Show us this "cherry-picking", you moronic dipshit. Show us your 'evidence' that Greenland used to be so much warmer and 'green' than it is now, and I mean 'evidence' other than the fact that the place got named 'Greenland" (I know things like that confuse retards like you).

The Medieval Warm Period in Greenland

The Medieval Warm Period in Greenland Reference
Vinther, B.M., Jones, P.D., Briffa, K.R., Clausen, H.B., Andersen, K.K., Dahl-Jensen, D. and Johnsen, S.J. 2010. Climatic signals in multiple highly resolved stable isotope records from Greenland. Quaternary Science Reviews 29: 522-538.

Background
The authors introduce the report of their new study by writing that "during the past 10 years studies of seasonal ice core δ18O records from the Greenland ice sheet have indicated, that in order to gain a firm understanding of the relationships between Greenland δ18O and climatic conditions in the North Atlantic region, it is important to have not only annually resolved, but seasonally resolved ice core δ18O data."

What was done
Working with 20 ice core records from 14 different sites, all of which stretched at least 200 years back in time, as well as near-surface air temperature data from 13 locations along the southern and western coasts of Greenland that covered approximately the same time interval (1784-2005), plus a similar temperature data set from northwest Iceland (said by the authors to be employed "in order to have some data indicative of climate east of the Greenland ice sheet"), Vinther et al. proceeded to demonstrate that winter δ18O was "the best proxy for Greenland temperatures." Then, based on that determination and working with three longer ice core δ18O records (DYE-3, Crete and GRIP), they developed a temperature history that extended more than 1400 years back in time.

What was learned
In the words of the seven scientists, "temperatures during the warmest intervals of the Medieval Warm Period," which they defined as occurring "some 900 to 1300 years ago, "were as warm as or slightly warmer than present day Greenland temperatures [italics added]."

What it means
As for what this result implies, the researchers conditionally -- and rather amusingly -- state that further warming of present day Greenland climate "will result in temperature conditions that are warmer than anything seen in the past 1400 years." But, of course, their work more directly and unconditionally implies that late 20th-century and early 21st-century weather has not yet been warm enough to confer "unprecedented" status upon Greenland air temperatures. What is more, Vinther et al. readily admit that the independent "GRIP borehole temperature inversion suggests that central Greenland temperatures are still somewhat below the high temperatures that existed during the Medieval Warm Period."

 

[Old Rocks]

The Vikings grazed cattle and sheep there in 800-1200 AD.

Doesn't mean it was balmy. That's totally ludicrous.

ROFL! It means it was a lot warmer than it is now. Do you imagine anyone could make a living as a farmer in Greenland now?

Ever consider research before making a fool of yourself, Pattycake?


Arctic Harvest: Global Warming a Boon for Greenland's Farmers - SPIEGEL ONLINE - News - International

Ferdinand Egede would be a perfectly normal farmer if it weren't for that loud cracking noise. Wearing a plaid lumberjack shirt and overalls, he hurries through the precise rows of his potato field, beads of sweat running down his forehead.

Egede, 49, occasionally picks up a handful of earth and rubs it between his solid fingers, but he isn't at all satisfied with the results. "It's much too dry," he says. "If I don't get the irrigation going, I'll lose my harvest."



The cracking noise has turned into a roar. What's happening in the sea below Egede's fields doesn't square well with what one would normally associate with rural life. The sound is that of an iceberg breaking apart, with pieces of it tumbling into the foaming sea.

Egede, a Greenland potato farmer, has little time to admire the view. He spends most of his days working in the fields and looking at the dramatically steep table mountains at the end of the fjord and the blue and white icebergs in the bay. But today he's more concerned about a broken water pipe. "The plants need a lot of water," he says, explaining that the soil here is very sandy, a result of glacier activity.

But he could still have a decent harvest. He pulled 20 tons of potatoes from the earth last summer, and his harvests have been growing larger each year. "It's already staying warm until November now," says Egede. And if this is what faraway scientists call the greenhouse effect, it's certainly a welcome phenomenon, as far as Egede as concerned.

 

[gslack]

Doesn't mean it was balmy. That's totally ludicrous.

ROFL! It means it was a lot warmer than it is now. Do you imagine anyone could make a living as a farmer in Greenland now?

Ever consider research before making a fool of yourself, Pattycake?


Arctic Harvest: Global Warming a Boon for Greenland's Farmers - SPIEGEL ONLINE - News - International

Ferdinand Egede would be a perfectly normal farmer if it weren't for that loud cracking noise. Wearing a plaid lumberjack shirt and overalls, he hurries through the precise rows of his potato field, beads of sweat running down his forehead.

Egede, 49, occasionally picks up a handful of earth and rubs it between his solid fingers, but he isn't at all satisfied with the results. "It's much too dry," he says. "If I don't get the irrigation going, I'll lose my harvest."



The cracking noise has turned into a roar. What's happening in the sea below Egede's fields doesn't square well with what one would normally associate with rural life. The sound is that of an iceberg breaking apart, with pieces of it tumbling into the foaming sea.

Egede, a Greenland potato farmer, has little time to admire the view. He spends most of his days working in the fields and looking at the dramatically steep table mountains at the end of the fjord and the blue and white icebergs in the bay. But today he's more concerned about a broken water pipe. "The plants need a lot of water," he says, explaining that the soil here is very sandy, a result of glacier activity.

But he could still have a decent harvest. He pulled 20 tons of potatoes from the earth last summer, and his harvests have been growing larger each year. "It's already staying warm until November now," says Egede. And if this is what faraway scientists call the greenhouse effect, it's certainly a welcome phenomenon, as far as Egede as concerned.

YES you should actually do some research first oldsocks...

ACTUALLY Reading the story right away we find 2 things of note.

1. that is in the southern most part of Greenland only. And more specifically a certain valley there.

2. By looking a t world map we can see the southern most part of Greenland is at the same latitude as Norway and a few other places that share that latitudinal designation. Norway has a strong agriculture there.

You are taking one area and likening it to all of Greenland. BTW the southern most areas of greenland are below the arctic circle.

 

[Old Rocks]

Dumb ass, that is the only part that the Viking colonized. Unlike the Innuit, they never learned to live in the cold lands.

 

[gslack]

Dumb ass, that is the only part that the Viking colonized. Unlike the Innuit, they never learned to live in the cold lands.

You were the dumb ass who posted it without reading it fully again..