Billy_Bob
Diamond Member
Which is why government monies and grants to "show desired results" should never happen.. Grants need to be done in the blind and have no preconceived outcome desired.
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AGW is a driver in mass extinction events
- Thread starter Crick
- Start date
airplanemechanic
Diamond Member
- Nov 8, 2014
- 17,995
- 13,099
- 2,415
How many species went extinct before man was ever on earth?
Extinction - Wikipedia
Over 99.9% of all species that ever walked the Earth are extinct.
Extinction - Wikipedia
Over 99.9% of all species that ever walked the Earth are extinct.
Last edited:
- Thread starter
- #43
Are you under the impression that all the mass extinction events took place during deglaciation? I'm afraid that is not the case.
Extinction event - Wikipedia
The Cretaceous–Paleogene (K–Pg) extinction event,[a] also known as the Cretaceous–Tertiary (K–T) extinction, was a sudden mass extinction of some three-quarters of the plant and animal species on Earth,[2][3][4]approximately 66 million years ago.[3] With the exception of some ectothermic species such as the leatherback sea turtle and crocodiles, no tetrapods weighing more than 25 kilograms (55 lb) survived.[5] It marked the end of the Cretaceous period and with it, the entire Mesozoic Era, opening the Cenozoic Era that continues today.
The Triassic–Jurassic extinction event marks the boundary between the Triassic and Jurassic periods, 201.3 million years ago,[1] and is one of the major extinction events of the Phanerozoic eon, profoundly affecting life on land and in the oceans. In the seas, a whole class (conodonts)[2] and 23-34% of marine genera disappeared.[3][4] On land, all archosaurs other than crocodylomorphs (Sphenosuchia and Crocodyliformes) and Avemetatarsalia (pterosaurs and dinosaurs), some remaining therapsids, and many of the large amphibians became extinct.
The Permian–Triassic (P–Tr or P–T) extinction event, colloquially known as the Great Dying,[2] the End-Permian Extinction or the Great Permian Extinction,[3][4] occurred about 252 Ma (million years) ago,[5]forming the boundary between the Permian and Triassic geologic periods, as well as between the Paleozoic and Mesozoic eras. It is the Earth's most severe known extinction event, with up to 96% of all marinespecies[6][7] and 70% of terrestrial vertebrate species becoming extinct.[8] It was the largest known mass extinction of insects. Some 57% of all biological families and 83% of all genera became extinct. Because so much biodiversity was lost, the recovery of land-dwelling life took significantly longer than after any other extinction event,[6] possibly up to 10 million years.[9] Studies in Bear Lake County, near Paris, Idaho, showed a relatively quick rebound in a localized marine ecosystem, taking around 2 million years to recover,[10] suggesting that the impact of the extinction may have been felt less severely in some areas than others.
The Late Devonian extinction was one of five major extinction events in the history of life on Earth. A major extinction, the Kellwasser event, occurred at the boundary that marks the beginning of the last phase of the Devonian period, the Famennian faunal stage (the Frasnian–Famennian boundary), about 376–360 million years ago.[1][2] Overall, 19% of all families and 50% of all genera became extinct.[3] A second, distinct mass extinction, the Hangenberg event, closed the Devonian period.[4]
The Ordovician–Silurian extinction events, when combined, are the second-largest of the five major extinction events in Earth's history in terms of percentage of genera that became extinct. This event greatly affected marine communities, which caused the disappearance of one third of all brachiopod and bryozoan families, as well as numerous groups of conodonts, trilobites, and graptolites.[1] The Ordovician–Silurian extinction occurred during the Hirnantian stage of the Ordovician Period and the subsequent Rhuddanian stage of the Silurian Period.[2] The last event is dated in the interval of 455–430 Ma ago, i.e., lasting from the Middle Ordovician to Early Silurian, thus including the extinction period.[3] This event was the first of the big five Phanerozoic events and was the first to significantly affect animal-based communities.[4]
From the same article in a discussion of potential causes:
Global cooling
Sustained and significant global cooling could kill many polar and temperate species and force others to migrate towards the equator; reduce the area available for tropical species; often make the Earth's climate more arid on average, mainly by locking up more of the planet's water in ice and snow. The glaciation cycles of the current ice age are believed to have had only a very mild impact on biodiversity, so the mere existence of a significant cooling is not sufficient on its own to explain a mass extinction.
It has been suggested that global cooling caused or contributed to the End-Ordovician, Permian–Triassic, Late Devonian extinctions, and possibly others. Sustained global cooling is distinguished from the temporary climatic effects of flood basalt events or impacts.
Global warming
This would have the opposite effects: expand the area available for tropical species; kill temperate species or force them to migrate towards the poles; possibly cause severe extinctions of polar species; often make the Earth's climate wetter on average, mainly by melting ice and snow and thus increasing the volume of the water cycle. It might also cause anoxic events in the oceans (see below).
Global warming as a cause of mass extinction is supported by several recent studies.[65]
The most dramatic example of sustained warming is the Paleocene–Eocene Thermal Maximum, which was associated with one of the smaller mass extinctions. It has also been suggested to have caused the Triassic–Jurassic extinction event, during which 20% of all marine families became extinct. Furthermore, the Permian–Triassic extinction event has been suggested to have been caused by warming.[66][67][68]
...
..
.
Anoxic events
Anoxic events are situations in which the middle and even the upper layers of the ocean become deficient or totally lacking in oxygen. Their causes are complex and controversial, but all known instances are associated with severe and sustained global warming, mostly caused by sustained massive volcanism.[70]
It has been suggested that anoxic events caused or contributed to the Ordovician–Silurian, late Devonian, Permian–Triassic and Triassic–Jurassic extinctions, as well as a number of lesser extinctions (such as the Ireviken, Mulde, Lau, Toarcian and Cenomanian–Turonianevents). On the other hand, there are widespread black shale beds from the mid-Cretaceous which indicate anoxic events but are not associated with mass extinctions.
The bio-availability of essential trace elements (in particular selenium) to potentially lethal lows has been shown to coincide with, and likely have contributed to, at least three mass extinction events in the oceans, i.e. at the end of the Ordovician, during the Middle and Late Devonian, and at the end of the Triassic. During periods of low oxygen concentrations very soluble selenate (Se6+) is converted into much less soluble selenide (Se2-), elemental Se and organo-selenium complexes. Bio-availability of selenium during these extinction events dropped to about 1% of the current oceanic concentration, a level that has been proven lethal to many extant organisms.[71]
I see nothing supporting your contention that these extinctions resulted from deglaciation.
Extinction event - Wikipedia
The Cretaceous–Paleogene (K–Pg) extinction event,[a] also known as the Cretaceous–Tertiary (K–T) extinction, was a sudden mass extinction of some three-quarters of the plant and animal species on Earth,[2][3][4]approximately 66 million years ago.[3] With the exception of some ectothermic species such as the leatherback sea turtle and crocodiles, no tetrapods weighing more than 25 kilograms (55 lb) survived.[5] It marked the end of the Cretaceous period and with it, the entire Mesozoic Era, opening the Cenozoic Era that continues today.
The Triassic–Jurassic extinction event marks the boundary between the Triassic and Jurassic periods, 201.3 million years ago,[1] and is one of the major extinction events of the Phanerozoic eon, profoundly affecting life on land and in the oceans. In the seas, a whole class (conodonts)[2] and 23-34% of marine genera disappeared.[3][4] On land, all archosaurs other than crocodylomorphs (Sphenosuchia and Crocodyliformes) and Avemetatarsalia (pterosaurs and dinosaurs), some remaining therapsids, and many of the large amphibians became extinct.
The Permian–Triassic (P–Tr or P–T) extinction event, colloquially known as the Great Dying,[2] the End-Permian Extinction or the Great Permian Extinction,[3][4] occurred about 252 Ma (million years) ago,[5]forming the boundary between the Permian and Triassic geologic periods, as well as between the Paleozoic and Mesozoic eras. It is the Earth's most severe known extinction event, with up to 96% of all marinespecies[6][7] and 70% of terrestrial vertebrate species becoming extinct.[8] It was the largest known mass extinction of insects. Some 57% of all biological families and 83% of all genera became extinct. Because so much biodiversity was lost, the recovery of land-dwelling life took significantly longer than after any other extinction event,[6] possibly up to 10 million years.[9] Studies in Bear Lake County, near Paris, Idaho, showed a relatively quick rebound in a localized marine ecosystem, taking around 2 million years to recover,[10] suggesting that the impact of the extinction may have been felt less severely in some areas than others.
The Late Devonian extinction was one of five major extinction events in the history of life on Earth. A major extinction, the Kellwasser event, occurred at the boundary that marks the beginning of the last phase of the Devonian period, the Famennian faunal stage (the Frasnian–Famennian boundary), about 376–360 million years ago.[1][2] Overall, 19% of all families and 50% of all genera became extinct.[3] A second, distinct mass extinction, the Hangenberg event, closed the Devonian period.[4]
The Ordovician–Silurian extinction events, when combined, are the second-largest of the five major extinction events in Earth's history in terms of percentage of genera that became extinct. This event greatly affected marine communities, which caused the disappearance of one third of all brachiopod and bryozoan families, as well as numerous groups of conodonts, trilobites, and graptolites.[1] The Ordovician–Silurian extinction occurred during the Hirnantian stage of the Ordovician Period and the subsequent Rhuddanian stage of the Silurian Period.[2] The last event is dated in the interval of 455–430 Ma ago, i.e., lasting from the Middle Ordovician to Early Silurian, thus including the extinction period.[3] This event was the first of the big five Phanerozoic events and was the first to significantly affect animal-based communities.[4]
From the same article in a discussion of potential causes:
Global cooling
Sustained and significant global cooling could kill many polar and temperate species and force others to migrate towards the equator; reduce the area available for tropical species; often make the Earth's climate more arid on average, mainly by locking up more of the planet's water in ice and snow. The glaciation cycles of the current ice age are believed to have had only a very mild impact on biodiversity, so the mere existence of a significant cooling is not sufficient on its own to explain a mass extinction.
It has been suggested that global cooling caused or contributed to the End-Ordovician, Permian–Triassic, Late Devonian extinctions, and possibly others. Sustained global cooling is distinguished from the temporary climatic effects of flood basalt events or impacts.
Global warming
This would have the opposite effects: expand the area available for tropical species; kill temperate species or force them to migrate towards the poles; possibly cause severe extinctions of polar species; often make the Earth's climate wetter on average, mainly by melting ice and snow and thus increasing the volume of the water cycle. It might also cause anoxic events in the oceans (see below).
Global warming as a cause of mass extinction is supported by several recent studies.[65]
The most dramatic example of sustained warming is the Paleocene–Eocene Thermal Maximum, which was associated with one of the smaller mass extinctions. It has also been suggested to have caused the Triassic–Jurassic extinction event, during which 20% of all marine families became extinct. Furthermore, the Permian–Triassic extinction event has been suggested to have been caused by warming.[66][67][68]
...
..
.
Anoxic events
Anoxic events are situations in which the middle and even the upper layers of the ocean become deficient or totally lacking in oxygen. Their causes are complex and controversial, but all known instances are associated with severe and sustained global warming, mostly caused by sustained massive volcanism.[70]
It has been suggested that anoxic events caused or contributed to the Ordovician–Silurian, late Devonian, Permian–Triassic and Triassic–Jurassic extinctions, as well as a number of lesser extinctions (such as the Ireviken, Mulde, Lau, Toarcian and Cenomanian–Turonianevents). On the other hand, there are widespread black shale beds from the mid-Cretaceous which indicate anoxic events but are not associated with mass extinctions.
The bio-availability of essential trace elements (in particular selenium) to potentially lethal lows has been shown to coincide with, and likely have contributed to, at least three mass extinction events in the oceans, i.e. at the end of the Ordovician, during the Middle and Late Devonian, and at the end of the Triassic. During periods of low oxygen concentrations very soluble selenate (Se6+) is converted into much less soluble selenide (Se2-), elemental Se and organo-selenium complexes. Bio-availability of selenium during these extinction events dropped to about 1% of the current oceanic concentration, a level that has been proven lethal to many extant organisms.[71]
I see nothing supporting your contention that these extinctions resulted from deglaciation.
Last edited:
Are you under the impression that all the mass extinction events took place during deglaciation? I'm afraid that is not the case.
https://en.wikipedia.org/wiki/Extinction_event
The Cretaceous–Paleogene (K–Pg) extinction event,[a] also known as the Cretaceous–Tertiary (K–T) extinction, was a sudden mass extinction of some three-quarters of the plant and animal species on Earth,[2][3][4]approximately 66 million years ago.[3] With the exception of some ectothermic species such as the leatherback sea turtle and crocodiles, no tetrapods weighing more than 25 kilograms (55 lb) survived.[5] It marked the end of the Cretaceous period and with it, the entire Mesozoic Era, opening the Cenozoic Era that continues today.
The Triassic–Jurassic extinction event marks the boundary between the Triassic and Jurassic periods, 201.3 million years ago,[1] and is one of the major extinction events of the Phanerozoic eon, profoundly affecting life on land and in the oceans. In the seas, a whole class (conodonts)[2] and 23-34% of marine genera disappeared.[3][4] On land, all archosaurs other than crocodylomorphs (Sphenosuchia and Crocodyliformes) and Avemetatarsalia (pterosaurs and dinosaurs), some remaining therapsids, and many of the large amphibians became extinct.
The Permian–Triassic (P–Tr or P–T) extinction event, colloquially known as the Great Dying,[2] the End-Permian Extinction or the Great Permian Extinction,[3][4] occurred about 252 Ma (million years) ago,[5]forming the boundary between the Permian and Triassic geologic periods, as well as between the Paleozoic and Mesozoic eras. It is the Earth's most severe known extinction event, with up to 96% of all marinespecies[6][7] and 70% of terrestrial vertebrate species becoming extinct.[8] It was the largest known mass extinction of insects. Some 57% of all biological families and 83% of all genera became extinct. Because so much biodiversity was lost, the recovery of land-dwelling life took significantly longer than after any other extinction event,[6] possibly up to 10 million years.[9] Studies in Bear Lake County, near Paris, Idaho, showed a relatively quick rebound in a localized marine ecosystem, taking around 2 million years to recover,[10] suggesting that the impact of the extinction may have been felt less severely in some areas than others.
The Late Devonian extinction was one of five major extinction events in the history of life on Earth. A major extinction, the Kellwasser event, occurred at the boundary that marks the beginning of the last phase of the Devonian period, the Famennian faunal stage (the Frasnian–Famennian boundary), about 376–360 million years ago.[1][2] Overall, 19% of all families and 50% of all genera became extinct.[3] A second, distinct mass extinction, the Hangenberg event, closed the Devonian period.[4]
The Ordovician–Silurian extinction events, when combined, are the second-largest of the five major extinction events in Earth's history in terms of percentage of genera that became extinct. This event greatly affected marine communities, which caused the disappearance of one third of all brachiopod and bryozoan families, as well as numerous groups of conodonts, trilobites, and graptolites.[1] The Ordovician–Silurian extinction occurred during the Hirnantian stage of the Ordovician Period and the subsequent Rhuddanian stage of the Silurian Period.[2] The last event is dated in the interval of 455–430 Ma ago, i.e., lasting from the Middle Ordovician to Early Silurian, thus including the extinction period.[3] This event was the first of the big five Phanerozoic events and was the first to significantly affect animal-based communities.[4]
From the same article in a discussion of potential causes:
Global cooling
Sustained and significant global cooling could kill many polar and temperate species and force others to migrate towards the equator; reduce the area available for tropical species; often make the Earth's climate more arid on average, mainly by locking up more of the planet's water in ice and snow. The glaciation cycles of the current ice age are believed to have had only a very mild impact on biodiversity, so the mere existence of a significant cooling is not sufficient on its own to explain a mass extinction.
It has been suggested that global cooling caused or contributed to the End-Ordovician, Permian–Triassic, Late Devonian extinctions, and possibly others. Sustained global cooling is distinguished from the temporary climatic effects of flood basalt events or impacts.
Global warming
This would have the opposite effects: expand the area available for tropical species; kill temperate species or force them to migrate towards the poles; possibly cause severe extinctions of polar species; often make the Earth's climate wetter on average, mainly by melting ice and snow and thus increasing the volume of the water cycle. It might also cause anoxic events in the oceans (see below).
Global warming as a cause of mass extinction is supported by several recent studies.[65]
The most dramatic example of sustained warming is the Paleocene–Eocene Thermal Maximum, which was associated with one of the smaller mass extinctions. It has also been suggested to have caused the Triassic–Jurassic extinction event, during which 20% of all marine families became extinct. Furthermore, the Permian–Triassic extinction event has been suggested to have been caused by warming.[66][67][68]
...
..
.
Anoxic events
Anoxic events are situations in which the middle and even the upper layers of the ocean become deficient or totally lacking in oxygen. Their causes are complex and controversial, but all known instances are associated with severe and sustained global warming, mostly caused by sustained massive volcanism.[70]
It has been suggested that anoxic events caused or contributed to the Ordovician–Silurian, late Devonian, Permian–Triassic and Triassic–Jurassic extinctions, as well as a number of lesser extinctions (such as the Ireviken, Mulde, Lau, Toarcian and Cenomanian–Turonianevents). On the other hand, there are widespread black shale beds from the mid-Cretaceous which indicate anoxic events but are not associated with mass extinctions.
The bio-availability of essential trace elements (in particular selenium) to potentially lethal lows has been shown to coincide with, and likely have contributed to, at least three mass extinction events in the oceans, i.e. at the end of the Ordovician, during the Middle and Late Devonian, and at the end of the Triassic. During periods of low oxygen concentrations very soluble selenate (Se6+) is converted into much less soluble selenide (Se2-), elemental Se and organo-selenium complexes. Bio-availability of selenium during these extinction events dropped to about 1% of the current oceanic concentration, a level that has been proven lethal to many extant organisms.[71]
I see nothing supporting your contention that these extinctions resulted from deglaciation.
Look man.. You're wasting your time trying to hook me here. You just went 3 pages of links to papers from DAMN NEAR every Period of Earth's development LOOKING for links between mass extinction and GW..
My comment ABOVE was for ONE of the links and papers -- the PERMIAN period... I don't PRETEND to cover a BILLION years of earth's history trying to scare the shit out of people by comparing those periods to the modern age climate and environment...
You're tossing too much crap out for ANYONE to be interested in calming you the fuck down..
Try slinging shit LESS and doing MORE critical thinking about the DIFFERENCES in those periods.. You remember PANGEA??? Think IT had the same global climate system we're trying to model TODAY???
- Thread starter
- #45
How many species went extinct before man was ever on earth?
Extinction - Wikipedia
Over 99% of all species that ever walked the Earth are extinct.
So... you don't mind if we go extinct? When we don't have to? I mean.... you don't think it's worth the effort? Is that what you're saying?
airplanemechanic
Diamond Member
- Nov 8, 2014
- 17,995
- 13,099
- 2,415
How many species went extinct before man was ever on earth?
Extinction - Wikipedia
Over 99% of all species that ever walked the Earth are extinct.
So... you don't mind if we go extinct? When we don't have to?
I would say that eventually man will be extinct. We're just another species. We've only been around about 10,000 years or so and according to the website I linked to, the lifespan of a species is 1-10 million years. We've got a ways to go but there is no reason we won't be extinct one day. If we get hit by another meteor I would expect we would go by way of the dinosaurs.
- Thread starter
- #47
Homo sapiens has been around for 200,000 years.
The extinction we're talking about is not from some unstoppable natural event. It is from our own actions of which we have had sufficient warming to have stopped the process. We do not HAVE to go extinct and the sort of fatalism required to not care seems unjustifiable.
The extinction we're talking about is not from some unstoppable natural event. It is from our own actions of which we have had sufficient warming to have stopped the process. We do not HAVE to go extinct and the sort of fatalism required to not care seems unjustifiable.
Billy_Bob
Diamond Member
You really are ignorant of history.Are you under the impression that all the mass extinction events took place during deglaciation? I'm afraid that is not the case.
Extinction event - Wikipedia
The Cretaceous–Paleogene (K–Pg) extinction event,[a] also known as the Cretaceous–Tertiary (K–T) extinction, was a sudden mass extinction of some three-quarters of the plant and animal species on Earth,[2][3][4]approximately 66 million years ago.[3] With the exception of some ectothermic species such as the leatherback sea turtle and crocodiles, no tetrapods weighing more than 25 kilograms (55 lb) survived.[5] It marked the end of the Cretaceous period and with it, the entire Mesozoic Era, opening the Cenozoic Era that continues today.
The Triassic–Jurassic extinction event marks the boundary between the Triassic and Jurassic periods, 201.3 million years ago,[1] and is one of the major extinction events of the Phanerozoic eon, profoundly affecting life on land and in the oceans. In the seas, a whole class (conodonts)[2] and 23-34% of marine genera disappeared.[3][4] On land, all archosaurs other than crocodylomorphs (Sphenosuchia and Crocodyliformes) and Avemetatarsalia (pterosaurs and dinosaurs), some remaining therapsids, and many of the large amphibians became extinct.
The Permian–Triassic (P–Tr or P–T) extinction event, colloquially known as the Great Dying,[2] the End-Permian Extinction or the Great Permian Extinction,[3][4] occurred about 252 Ma (million years) ago,[5]forming the boundary between the Permian and Triassic geologic periods, as well as between the Paleozoic and Mesozoic eras. It is the Earth's most severe known extinction event, with up to 96% of all marinespecies[6][7] and 70% of terrestrial vertebrate species becoming extinct.[8] It was the largest known mass extinction of insects. Some 57% of all biological families and 83% of all genera became extinct. Because so much biodiversity was lost, the recovery of land-dwelling life took significantly longer than after any other extinction event,[6] possibly up to 10 million years.[9] Studies in Bear Lake County, near Paris, Idaho, showed a relatively quick rebound in a localized marine ecosystem, taking around 2 million years to recover,[10] suggesting that the impact of the extinction may have been felt less severely in some areas than others.
The Late Devonian extinction was one of five major extinction events in the history of life on Earth. A major extinction, the Kellwasser event, occurred at the boundary that marks the beginning of the last phase of the Devonian period, the Famennian faunal stage (the Frasnian–Famennian boundary), about 376–360 million years ago.[1][2] Overall, 19% of all families and 50% of all genera became extinct.[3] A second, distinct mass extinction, the Hangenberg event, closed the Devonian period.[4]
The Ordovician–Silurian extinction events, when combined, are the second-largest of the five major extinction events in Earth's history in terms of percentage of genera that became extinct. This event greatly affected marine communities, which caused the disappearance of one third of all brachiopod and bryozoan families, as well as numerous groups of conodonts, trilobites, and graptolites.[1] The Ordovician–Silurian extinction occurred during the Hirnantian stage of the Ordovician Period and the subsequent Rhuddanian stage of the Silurian Period.[2] The last event is dated in the interval of 455–430 Ma ago, i.e., lasting from the Middle Ordovician to Early Silurian, thus including the extinction period.[3] This event was the first of the big five Phanerozoic events and was the first to significantly affect animal-based communities.[4]
From the same article in a discussion of potential causes:
Global cooling
Sustained and significant global cooling could kill many polar and temperate species and force others to migrate towards the equator; reduce the area available for tropical species; often make the Earth's climate more arid on average, mainly by locking up more of the planet's water in ice and snow. The glaciation cycles of the current ice age are believed to have had only a very mild impact on biodiversity, so the mere existence of a significant cooling is not sufficient on its own to explain a mass extinction.
It has been suggested that global cooling caused or contributed to the End-Ordovician, Permian–Triassic, Late Devonian extinctions, and possibly others. Sustained global cooling is distinguished from the temporary climatic effects of flood basalt events or impacts.
Global warming
This would have the opposite effects: expand the area available for tropical species; kill temperate species or force them to migrate towards the poles; possibly cause severe extinctions of polar species; often make the Earth's climate wetter on average, mainly by melting ice and snow and thus increasing the volume of the water cycle. It might also cause anoxic events in the oceans (see below).
Global warming as a cause of mass extinction is supported by several recent studies.[65]
The most dramatic example of sustained warming is the Paleocene–Eocene Thermal Maximum, which was associated with one of the smaller mass extinctions. It has also been suggested to have caused the Triassic–Jurassic extinction event, during which 20% of all marine families became extinct. Furthermore, the Permian–Triassic extinction event has been suggested to have been caused by warming.[66][67][68]
...
..
.
Anoxic events
Anoxic events are situations in which the middle and even the upper layers of the ocean become deficient or totally lacking in oxygen. Their causes are complex and controversial, but all known instances are associated with severe and sustained global warming, mostly caused by sustained massive volcanism.[70]
It has been suggested that anoxic events caused or contributed to the Ordovician–Silurian, late Devonian, Permian–Triassic and Triassic–Jurassic extinctions, as well as a number of lesser extinctions (such as the Ireviken, Mulde, Lau, Toarcian and Cenomanian–Turonianevents). On the other hand, there are widespread black shale beds from the mid-Cretaceous which indicate anoxic events but are not associated with mass extinctions.
The bio-availability of essential trace elements (in particular selenium) to potentially lethal lows has been shown to coincide with, and likely have contributed to, at least three mass extinction events in the oceans, i.e. at the end of the Ordovician, during the Middle and Late Devonian, and at the end of the Triassic. During periods of low oxygen concentrations very soluble selenate (Se6+) is converted into much less soluble selenide (Se2-), elemental Se and organo-selenium complexes. Bio-availability of selenium during these extinction events dropped to about 1% of the current oceanic concentration, a level that has been proven lethal to many extant organisms.[71]
I see nothing supporting your contention that these extinctions resulted from deglaciation.
Tell Me Crick, which one of those events do you think were caused by CO2 levels? How does it correlate to today's levels? Do you have even a corollary link at all?
When your done hyperventilating and can think rationally maybe you will think cognitively. Then again maybe not...
Billy_Bob
Diamond Member
This is his hope. If he tosses out enough useless garbage, then he hopes people will believe, even though he hasn't a shred of empirical evidence to support his hyperbole...You're tossing too much crap out for ANYONE to be interested in calming you the fuck down..
If you cant baffle them with brilliance, baffle them with bull shit..
Manonthestreet
Diamond Member
- May 20, 2014
- 34,699
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yeah are they supposed to be gone by now.....still begging people to burn massive amounts of carbon to fly down and give em money,,,,hypocrites allIt looks to me as if they damn near pegged it back in 1988.
On front line of climate change as Maldives fights rising seas
Manonthestreet
Diamond Member
- May 20, 2014
- 34,699
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sure ya do......main industry....I could be wrong, but I don't think you need to fly down there to give them money.
- May 20, 2009
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Numerous studies have concluded that we are moving into the Earth's sixth mass extinction event. The cause are almost all anthropogenic: pollution, loss of habitat, global warming, disruption of predator/prey relationships, migratory changes, introduction of new diseases, etc.
This study finds that increased levels of anthropogenic global warming lead to increased number of species extinction events. Acting to mitigate AGW will limit the number of species lost.
Extinction risk from climate change
Abstract
Climate change over the past ∼30 years has produced numerous shifts in the distributions and abundances of species1,2 and has been implicated in one species-level extinction3. Using projections of species' distributions for future climate scenarios, we assess extinction risks for sample regions that cover some 20% of the Earth's terrestrial surface. Exploring three approaches in which the estimated probability of extinction shows a power-law relationship with geographical range size, we predict, on the basis of mid-range climate-warming scenarios for 2050, that 15–37% of species in our sample of regions and taxa will be ‘committed to extinction’. When the average of the three methods and two dispersal scenarios is taken, minimal climate-warming scenarios produce lower projections of species committed to extinction (∼18%) than mid-range (∼24%) and maximum-change (∼35%) scenarios. These estimates show the importance of rapid implementation of technologies to decrease greenhouse gas emissions and strategies for carbon sequestration.
Asteroids cause global warming?
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We should have listened! Look at the Maldives today
Billy_Bob
Diamond Member
Did I miss Guam flipping over?We should have listened! Look at the Maldives today
Last edited:
SSDD
Gold Member
- Nov 6, 2012
- 16,672
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Study concludes End Permian Extinction was caused by global warming.
Article: Biggest mass extinction caused by global warming leaving ocean animals gasping for breath
More reading at Temperature-dependent hypoxia explains biogeography and severity of end-Permian marine mass extinction
Abstract
Rapid climate change at the end of the Permian Period (~252 million years ago) is the hypothesized trigger for the largest mass extinction in Earth’s history. We present model simulations of the Permian/Triassic climate transition that reproduce the ocean warming and oxygen (O2) loss indicated by the geologic record. The effect of these changes on animal survival is evaluated using the Metabolic Index (Φ), a measure of scope for aerobic activity governed by organismal traits sampled in diverse modern species. Modeled loss of aerobic habitat predicts lower extinction intensity in the tropics, a pattern confirmed with a spatially explicit analysis of the marine fossil record. The combined physiological stresses of ocean warming and O2 loss can account for more than half the magnitude of the “Great Dying.”
The permian extinction was due to cooling..
https://onlinelibrary.wiley.com/doi/abs/10.1111/let.12252
Clip: “A sea-level drop of nearly 100 m can be achieved solely by transferring vast seawater onto land in the form of ice. It is noteworthy that sea level was much higher in the Late Ordovician (ca. 60 m above the present-day level) than in the Middle Permian (ca. 80 m below the present-day level), even after the sea-level drop in the same magnitude.”
https://www.researchgate.net/public...apse_in_NE_Japan_and_Primorye_Far_East_Russia
Clip:
the sea level during the Capitanian contradictorily recorded the lowest stand of the Phanerozoic (Haq and Schutter, 2008), suggesting a global cooling instead. Ice coverage and/or the predominance of arid climates under cooling during the Permian likely accelerated the decrease in the seawater Sr ratio.”
Sea level drop, palaeoenvironmental change and related biotic responses across Guadalupian–Lopingian boundary in southwest, North and Central Iran | Geological Magazine | Cambridge Core
Clip: “The sea level drop and regression as a cause for end-Guadalupian extinction have also been reported in the Middle to Late Permian deposits in the Kuh-e Gahkum section in Zagros (Kolodka et al. 2012). This sea level fall and regression is in concert with the Permian global eustatic curve (Haq & Schutter, 2008), which signifies the lowest sea level during the Palaeozoic at the end of the Capitanian. The cause of this sea level fall is unclear. Isozaki, Kawahata & Ota (2007), Isozaki, Aljinovic & Kawahata (2011) and Kofukuda, Isozaki & Igo (2014) have speculated that global cooling was a causal factor in the late Capitanian regression. The Capitanian high positive plateau interval of carbonate carbon isotope ratio (δ13Ccarb), known as the Kamura event, has been suggested as confirmation of this cooling event.”
SSDD
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- Nov 6, 2012
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View attachment 253168
You people are so damn predictable.... Not even empirical evidence calling you out liars stops the boy who cries wolf...
Show us some empirical evidence that proves I am a liar Billy.
You have been caught in so many lies that it isn't even fun catching you anymore...
Billy_Bob
Diamond Member
Any post showing your use of failed modeling will do.. You have been shown over and over of the lie, yet you still spout it as truth... Its now tedious to keep calling you out..View attachment 253168
You people are so damn predictable.... Not even empirical evidence calling you out liars stops the boy who cries wolf...
Show us some empirical evidence that proves I am a liar Billy.
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