CarnegieGlobEcology just uploaded a video

[Andrew Lockley]

CarnegieGlobEcology just uploaded a video:

The Great Climate Experiment: How far can we push the planet? Ken Caldeira [Scientific American]
Ken Caldeira discussing his article in the August 2012 issue of Scientific American.

The article is titled "The Great Climate Experiment. How far can we push the planet?" It extends from page 78 to page 83.

http://dge.stanford.edu/labs/caldeiralab/
http://www.scientificamerican.com/sciammag/ more
user by visiting My Subscriptions.

© 2012 YouTube, LLC
901 Cherry Ave, San Bruno, CA 94066

[Andrew Lockley]

Link got stripped, sorry

http://www.youtube.com/watch?v=64Ole0VCbAE&feature=em-uploademail

[Mike MacCracken]

I was surprised there was no mention of sea level rise and the dislocations that will result on coastlines around the world. And because this has such a long time constant, this will be issue that goes on and one. That is going to be a quite expensive impact to adapt to.

On water, one could assume desalination will become less expensive and food growing will be hydroponic, etc.

I think the ecosystem and species loss issue is likely much more serious than mentioned—going to Cretaceous 6 C or so higher temperature would likely really cause dislocations and disruptions of interactions and linkages within ecosystems.

Ocean acidification is likely also to cause at least some disruptions of marine ecosystems, etc.--not just coral reefs, or at least there is risk of much more.

And if it keeps going, we’ll all be wanting homes on Greenland and Antarctica.

Mike

[David Lewis]

Caldeira states he was asked by SciAm editors "what would happen if...  we burned ALL the fossil fuels available and dumped that CO2 into the atmosphere", and he claims he took some pains with his answer so it would stand up to the scrutiny of his scientific colleagues.  At minute 2:00 he then states:  "it might be that for the middle classes of the industrial world that climate change is really a secondary issue and they'll still have their TV sets and their McBurgers and McNuggets to eat and life would go on...."

Matthias Honegger translated an interview Hanna Wick conducted with Ken Caldeira that was published in German and posted it for this group here.  His translation of what Caldeira said in that interview went a bit further than in this SciAm video:  Honegger translated Caldeira in this way:  "My opinion is that climate change will be an ecological disaster. For most middle-class people in developed countries it will not be felt very strongly".  

I wonder how these statements are received by Caldeira's scientific colleagues.  

The time frame for the event, i.e. burning of all the fossil fuels, and the consequence, what would happen, appear to be different.  Maybe he is thinking about the middle classes in 2050, or even by 2100, when many consequences will still be "in the pipeline", and in any case it will not have been possible to burn all the fossil fuels yet.  If Caldeira actually believes it is possible to burn ALL the fossil fuels and have the average middle class person in developed countries not feel the consequences very strongly, how is it that apparently, so many of his colleagues disagree with him?  

I'd like to know where I've gone wrong in my effort to understand what scientists believe.  

Consider the publicly expressed views of John Schellnhuber of PIK, who stood before the audience at the 4 degrees conference held in Australia and after telling them their Great Barrier Reef was doomed even if civilization managed what seems now to be the almost impossible goal of limiting global warming to 2 degrees C, asked them if very many of them play Russian Roulette at home.  He then explained that even if civilization limited global warming to 2 degrees the odds were worse than 1 in 6 that tipping points would be passed anyway which would threaten the existence of civilization.    

Perhaps Caldeira assumes geoengineering research has reached a point where he can assume it will be employed, and the planet can be successfully cooled no matter if all the fossil fuels are burned, and that civilization can survive relatively unscathed as the biosphere is disrupted wholesale in the high CO2 artificially cooled world?  

Is Kevin Anderson of the Tyndall Centre, who says there is "a widespread view" among top flight scientists he is in contact with that a mere 4 degrees C warming will prove to be "incompatible with an organized global community" and have a "high probability of not being stable", aware of Caldeira's views?  

[Ken Caldeira]

First:  There was an error in a title slide of the YouTube video, the updated video is here:  http://www.youtube.com/watch?v=ce2OWROToAI

Regarding Mike MacCracken's mention of sea-level, in the Scientific American article (http://www.scientificamerican.com/article.cfm?id=how-far-can-climate-change-go, subscription required), I wrote:

In high-CO2 times in the ancient past,

Earth warmed enough for crocodilelike

animals to live north of the Arctic Circle.

Roughly 100 million years ago annual average

polar temperatures reached 14 degrees

C, with summertime temperatures

exceeding 25 degrees C. Over thousands

of years temperatures of this magnitude

would be sufficient to melt the great ice

sheets of Greenland and Antarctica. With

the ice sheets melted completely, sea level

will be about 120 meters higher, flooding

vast areas. That water’s weight on low-

lying continental regions will push those

areas down farther into the mantle, causing

the waters to lap even higher.

The poles are expected to warm about

2.5 times faster than Earth as a whole. Already

the Arctic has warmed faster than

anywhere else, by about two degrees C

compared with 0.8 degree C globally. At

the end of the last ice age, when the climate

warmed by about five degrees C over

thousands of years, the ice sheets melted

at a rate that caused sea level to rise about

one meter per century. We hope and expect

that ice sheets will not melt more rapidly

this time, but we cannot be certain.

A long-term outlook of 120 m of sea-level rise with a mean rate of 1 m per century and a risk of more sudden increase seems to me neither too alarmist nor too sanguine. Some of what I wrote on sea-level got cut out in editing.

Regarding 'catastrophe', in the YouTube video (http://www.youtube.com/watch?v=ce2OWROToAI) I say (somewhat, inarticulately):

So then the question comes to us, well, is this going to be a catastrophe or is this just something we’re going to deal with?  And I think we can say with a pretty high degree of certainty that it’s going to be catastrophic for at least some ecosystems.  I think the clearest is probably coral reefs are severely challenged by both ocean acidification and global warming.  Arctic ecosystems are probably in big trouble, and it might also be places like rainforests and so on might also be in big trouble.

 

Now, what about humans?  I think there’s a few things.  One is that, obviously, if you’re a poor subsistence community depending on coral reefs, you’re probably in trouble.  Maybe also if you’re a similar subsistence society depending on growing food in a place where you’re going to have big droughts that you’re also going to be in trouble.  But it might be that for the middle classes of the industrialized world that climate change is really a secondary issue, and that they’ll still have their TV sets and their McBurgers and McNuggets to eat and that life will go on.

 

That said, we don’t really know that that’s true.  If we look at the 2008 subprime mortgage crisis, there you had perturbations in some financial markets that led to a 5% loss in GDP throughout the world.  And so our economic system can take some regional perturbation to amplify it into a global crisis.  Also, these days, you have countries where you have nuclear arm nations, and if they feel they have an existential threat, there’s potential for war and so on.

 

So one issue is, since most catastrophic effects of climate change are likely to show up regionally, in some sort of regional drought or storms or floods or something else like that, are these social and political systems going to amplify these regional crises and form a global crisis out of it?  And I think we don’t really know the answers to these questions.  We know that our continued emissions of CO2 is increasing our levels of environmental risk, but it’s really hard to quantify exactly how much risk we’re facing.

Again, I think this is neither overly alarmist nor overly sanguine.

In the Scientific American piece, I wrote:

What will thrive in this hothouse? Some

organisms, such as rats and cockroaches,

are invasive generalists, which can take advantage

of disrupted environments. Other

organisms, such as corals and many tropical

forest species, have evolved to thrive in

a narrow range of conditions. Invasive species

will likely transform such ecosystems

as a result of global warming. Climate

change may usher in a world of weeds.

Human civilization is also at risk. Consider

the Mayans. Even before Europeans

arrived, the Mayan civilization had begun

to collapse thanks to relatively minor climate

changes. The Mayans had not developed

enough resilience to weather small

reductions in rainfall, and the Mayans

are not alone as examples of civilizations

that failed to adapt to climate changes.

Crises provoked by climate change are

likely to be regional. If the rich get richer

and the poor get poorer, could this set in

motion mass migrations that challenge

political and economic stability? Some of

the same countries that are most likely

to suffer from the changes wrought by

global warming also boast nuclear weapons.

Could climate change exacerbate existing

tensions and provoke nuclear or

other apocalyptic conflict? The social response

to climate change could produce

bigger problems for humanity than the

climate change itself.

I am pretty sure that I did not say exactly the words that were attributed to me by first translating what I said into German and then back into English. That said, I do believe that it is entirely possible that for middle class people in the industrialized world, climate change may end up being an annoyance and not a central concern.  As I say above, it could also prove catastrophic.  I just don't think we know or have a way of knowing.

We can act to reduce risk, and that mostly means transforming our systems of energy production and consumption.

Also, one person's catastrophe is another person's cost, so some of what we are talking about is the application of language and not a difference in understanding of the facts. Health consequences of black-carbon-particulates are a societal cost of diesel trucking, but if you are the one with lung cancer, it is a catastrophe. 

Best,

Ken

PS. If someone wants a proof-copy of the Scientific American piece for personal use, you can email me requesting a copy.

_______________
Ken Caldeira

Carnegie Institution for Science 

Dept of Global Ecology

260 Panama Street, Stanford, CA 94305 USA

+1 650 704 7212 kcal...@carnegiescience.edu

http://dge.stanford.edu/labs/caldeiralab  @kencaldeira

Our YouTube videos

Attribution of atmospheric CO2 and temperature increases to regions: Ken Caldeira

Climate change and the transition from coal to low-carbon electricity: Ken Caldeira  

More videos

--
You received this message because you are subscribed to the Google Groups "geoengineering" group.

To view this discussion on the web visit https://groups.google.com/d/msg/geoengineering/-/WNHPgLBYuz8J.

To post to this group, send email to geoengi...@googlegroups.com.
To unsubscribe from this group, send email to geoengineerin...@googlegroups.com.
For more options, visit this group at http://groups.google.com/group/geoengineering?hl=en.

[Andrew Lockley]

Ken

I remain concerned that the risk of ocean anoxia is missing from your video. 

Anoxia appears to me to be the most likely 'unsurvivable ' climate change risk.  Consequently, it is to my mind perhaps the best example of the  central argument for geoengineering -  existential threat (particularly if the PT extinction is anything to go by) .

Perhaps you could set out why you chose not to include it?

Thanks

A

[Ken Caldeira]

If  we are concerned mostly about anoxia caused by global warming,based on the review of Keeling et al (2010) attached, we can expect a 4% (+/- 3 %) decline in the ocean oxygen inventory over the next century. This is certainly important and should be studied more carefully, but I do not think it represents an existential threat for humans although it may be an existential threat for some marine species and is likely to exacerbate environmental problems in some regions.

For example, anoxia is certainly an issue in places like the Gulf of Mexico near the mouth of the Mississippi River, where nutrients are causing plankton blooms that result in anoxic conditions.

Climate has been hot in the Cretaceous and the oceans seem to have supported a lot of life.   Ecosystems will need to adjust and organisms with high metabolic rates that live in warm water will be disadvantaged, but I do not see anoxia as limiting net primary productivity in ecosystems of the upper ocean. It may affect species composition but not overall oceanic productivity. Ocean anoxic areas in the deep ocean will expand, but it is unclear to me how that represents an existential threat to humans.

----

Part of what I am trying to communicate is that we should feel a responsibility to pass our environmental endowment on to future generations even if our damage to the environment do not represent an existential threat to humans.  

We are liquidating our environmental capital so that we can increase current consumption, and this is unwise. 

_______________
Ken Caldeira

Carnegie Institution for Science 

Dept of Global Ecology

260 Panama Street, Stanford, CA 94305 USA

+1 650 704 7212 kcal...@carnegiescience.edu

http://dge.stanford.edu/labs/caldeiralab  @kencaldeira

Our YouTube videos

Attribution of atmospheric CO2 and temperature increases to regions: Ken Caldeira

Climate change and the transition from coal to low-carbon electricity: Ken Caldeira  

More videos

[Mike MacCracken]

Any thoughts on what the ocean circulation might be with a 70 meter or so SL rise? Might we have a lot larger shallow continental shelves? Will it still be cold that makes water sink, or will warm, salty water be what sinks?

Mike

PS—And what I thought strangest was saying that people might still be using phones, etc.--I’d venture it would be closer to us having implants so we can think a message that gets picked up by external hotspots and passes along the communication.

On 8/15/12 7:34 PM, "Ken Caldeira" <kcal...@carnegiescience.edu> wrote:

If  we are concerned mostly about anoxia caused by global warming,based on the review of Keeling et al (2010) attached, we can expect a 4% (+/- 3 %) decline in the ocean oxygen inventory over the next century. This is certainly important and should be studied more carefully, but I do not think it represents an existential threat for humans although it may be an existential threat for some marine species and is likely to exacerbate environmental problems in some regions.

For example, anoxia is certainly an issue in places like the Gulf of Mexico near the mouth of the Mississippi River, where nutrients are causing plankton blooms that result in anoxic conditions.

Climate has been hot in the Cretaceous and the oceans seem to have supported a lot of life.   Ecosystems will need to adjust and organisms with high metabolic rates that live in warm water will be disadvantaged, but I do not see anoxia as limiting net primary productivity in ecosystems of the upper ocean. It may affect species composition but not overall oceanic productivity. Ocean anoxic areas in the deep ocean will expand, but it is unclear to me how that represents an existential threat to humans.

----

Part of what I am trying to communicate is that we should feel a responsibility to pass our environmental endowment on to future generations even if our damage to the environment do not represent an existential threat to humans.  

We are liquidating our environmental capital so that we can increase current consumption, and this is unwise. 


_______________
Ken Caldeira

Carnegie Institution for Science 
Dept of Global Ecology
260 Panama Street, Stanford, CA 94305 USA
+1 650 704 7212 kcal...@carnegiescience.edu
http://dge.stanford.edu/labs/caldeiralab  @kencaldeira

Our YouTube videos
Attribution of atmospheric CO2 and temperature increases to regions: Ken Caldeira <http://www.youtube.com/watch?v=zRh_Zfr6A08>
Climate change and the transition from coal to low-carbon electricity: Ken Caldeira <http://www.youtube.com/watch?v=a9LaYCbYCxo>   
More videos <http://dge.stanford.edu/labs/caldeiralab/Caldeira_Videos.html>

+1 650 704 7212 <tel:%2B1%20650%20704%207212>  kcal...@carnegiescience.edu
http://dge.stanford.edu/labs/caldeiralab  @kencaldeira

Our YouTube videos
Attribution of atmospheric CO2 and temperature increases to regions: Ken Caldeira <http://www.youtube.com/watch?v=zRh_Zfr6A08>
Climate change and the transition from coal to low-carbon electricity: Ken Caldeira <http://www.youtube.com/watch?v=a9LaYCbYCxo>   
More videos <http://dge.stanford.edu/labs/caldeiralab/Caldeira_Videos.html>

On Wed, Aug 15, 2012 at 9:06 AM, David Lewis <jrando...@gmail.com> wrote:

Caldeira states he was asked by SciAm editors "what would happen if...  we burned ALL the fossil fuels available and dumped that CO2 into the atmosphere", and he claims he took some pains with his answer so it would stand up to the scrutiny of his scientific colleagues.  At minute 2:00 he then states:  "it might be that for the middle classes of the industrial world that climate change is really a secondary issue and they'll still have their TV sets and their McBurgers and McNuggets to eat and life would go on...."

Matthias Honegger translated an interview Hanna Wick conducted with Ken Caldeira that was published in German and posted it for this group here <https://groups.google.com/group/geoengineering/tree/browse_frm/thread/51bdd45979ce24a3/a97348bd8422e04e?hide_quotes=no> .  His translation of what Caldeira said in that interview went a bit further than in this SciAm video:  Honegger translated Caldeira in this way:  "My opinion is that climate change will be an ecological disaster. For most middle-class people in developed countries it will not be felt very strongly".  

I wonder how these statements are received by Caldeira's scientific colleagues.  

The time frame for the event, i.e. burning of all the fossil fuels, and the consequence, what would happen, appear to be different.  Maybe he is thinking about the middle classes in 2050, or even by 2100, when many consequences will still be "in the pipeline", and in any case it will not have been possible to burn all the fossil fuels yet.  If Caldeira actually believes it is possible to burn ALL the fossil fuels and have the average middle class person in developed countries not feel the consequences very strongly, how is it that apparently, so many of his colleagues disagree with him?  

I'd like to know where I've gone wrong in my effort to understand what scientists believe.  

Consider the publicly expressed views of John Schellnhuber of PIK, who stood before the audience at the 4 degrees conference held in Australia and after telling them their Great Barrier Reef was doomed even if civilization managed what seems now to be the almost impossible goal of limiting global warming to 2 degrees C, asked them if very many of them play Russian Roulette at home.  He then explained that even if civilization limited global warming to 2 degrees the odds were worse than 1 in 6 that tipping points would be passed anyway which would threaten the existence of civilization.    

Perhaps Caldeira assumes geoengineering research has reached a point where he can assume it will be employed, and the planet can be successfully cooled no matter if all the fossil fuels are burned, and that civilization can survive relatively unscathed as the biosphere is disrupted wholesale in the high CO2 artificially cooled world?  

Is Kevin Anderson of the Tyndall Centre, who says there is "a widespread view" among top flight scientists he is in contact with that a mere 4 degrees C warming will prove to be "incompatible with an organized global community" and have a "high probability of not being stable", aware of Caldeira's views?  




On Tuesday, August 14, 2012 3:22:07 PM UTC-7, andrewjlockley wrote:

CarnegieGlobEcology just uploaded a video:

The Great Climate Experiment: How far can we push the planet? Ken Caldeira [Scientific American]
Ken Caldeira discussing his article in the August 2012 issue of Scientific American.

The article is titled "The Great Climate Experiment. How far can we push the planet?" It extends from page 78 to page 83.

http://dge.stanford.edu/labs/caldeiralab/ <http://dge.stanford.edu/labs/caldeiralab/>
http://www.scientificamerican.com/sciammag/ <http://www.scientificamerican.com/sciammag/>  more

[Rau, Greg]

If anoxia expands so does preservation of sedimentary organic material, thus increasing the efficiency of the marine biological CO2 pump, assuming surface nutrients are constant. On the flip side there would be greater production of NO2, CH4 and H2S gases with GW consequences. Other concerns? I should read Keeling et al.
-Greg
-
________________________________________
From: geoengi...@googlegroups.com [geoengi...@googlegroups.com] On Behalf Of Ken Caldeira [kcal...@carnegiescience.edu]
Sent: Wednesday, August 15, 2012 4:34 PM
To: Andrew Lockley
Cc: geoengineering
Subject: Re: [geo] Re: CarnegieGlobEcology just uploaded a video

If we are concerned mostly about anoxia caused by global warming,based on the review of Keeling et al (2010) attached, we can expect a 4% (+/- 3 %) decline in the ocean oxygen inventory over the next century. This is certainly important and should be studied more carefully, but I do not think it represents an existential threat for humans although it may be an existential threat for some marine species and is likely to exacerbate environmental problems in some regions.

For example, anoxia is certainly an issue in places like the Gulf of Mexico near the mouth of the Mississippi River, where nutrients are causing plankton blooms that result in anoxic conditions.

Climate has been hot in the Cretaceous and the oceans seem to have supported a lot of life. Ecosystems will need to adjust and organisms with high metabolic rates that live in warm water will be disadvantaged, but I do not see anoxia as limiting net primary productivity in ecosystems of the upper ocean. It may affect species composition but not overall oceanic productivity. Ocean anoxic areas in the deep ocean will expand, but it is unclear to me how that represents an existential threat to humans.

----

Part of what I am trying to communicate is that we should feel a responsibility to pass our environmental endowment on to future generations even if our damage to the environment do not represent an existential threat to humans.

We are liquidating our environmental capital so that we can increase current consumption, and this is unwise.


_______________
Ken Caldeira

Carnegie Institution for Science
Dept of Global Ecology
260 Panama Street, Stanford, CA 94305 USA

+1 650 704 7212 kcal...@carnegiescience.edu<mailto:kcal...@carnegiescience.edu>

http://dge.stanford.edu/labs/caldeiralab @kencaldeira

Our YouTube videos

Attribution of atmospheric CO2 and temperature increases to regions: Ken Caldeira<http://www.youtube.com/watch?v=zRh_Zfr6A08>
Climate change and the transition from coal to low-carbon electricity: Ken Caldeira<http://www.youtube.com/watch?v=a9LaYCbYCxo>
More videos<http://dge.stanford.edu/labs/caldeiralab/Caldeira_Videos.html>

On Wed, Aug 15, 2012 at 4:07 PM, Andrew Lockley <andrew....@gmail.com<mailto:andrew....@gmail.com>> wrote:

Ken

I remain concerned that the risk of ocean anoxia is missing from your video.

Anoxia appears to me to be the most likely 'unsurvivable ' climate change risk. Consequently, it is to my mind perhaps the best example of the central argument for geoengineering - existential threat (particularly if the PT extinction is anything to go by) .

Perhaps you could set out why you chose not to include it?

Thanks

A

+1 650 704 7212<tel:%2B1%20650%20704%207212> kcal...@carnegiescience.edu<mailto:kcal...@carnegiescience.edu>

http://dge.stanford.edu/labs/caldeiralab @kencaldeira

Our YouTube videos

Attribution of atmospheric CO2 and temperature increases to regions: Ken Caldeira<http://www.youtube.com/watch?v=zRh_Zfr6A08>
Climate change and the transition from coal to low-carbon electricity: Ken Caldeira<http://www.youtube.com/watch?v=a9LaYCbYCxo>
More videos<http://dge.stanford.edu/labs/caldeiralab/Caldeira_Videos.html>

On Wed, Aug 15, 2012 at 9:06 AM, David Lewis <jrando...@gmail.com<mailto:jrando...@gmail.com>> wrote:
Caldeira states he was asked by SciAm editors "what would happen if... we burned ALL the fossil fuels available and dumped that CO2 into the atmosphere", and he claims he took some pains with his answer so it would stand up to the scrutiny of his scientific colleagues. At minute 2:00 he then states: "it might be that for the middle classes of the industrial world that climate change is really a secondary issue and they'll still have their TV sets and their McBurgers and McNuggets to eat and life would go on...."

Matthias Honegger translated an interview Hanna Wick conducted with Ken Caldeira that was published in German and posted it for this group here<https://groups.google.com/group/geoengineering/tree/browse_frm/thread/51bdd45979ce24a3/a97348bd8422e04e?hide_quotes=no>. His translation of what Caldeira said in that interview went a bit further than in this SciAm video: Honegger translated Caldeira in this way: "My opinion is that climate change will be an ecological disaster. For most middle-class people in developed countries it will not be felt very strongly".

I wonder how these statements are received by Caldeira's scientific colleagues.

The time frame for the event, i.e. burning of all the fossil fuels, and the consequence, what would happen, appear to be different. Maybe he is thinking about the middle classes in 2050, or even by 2100, when many consequences will still be "in the pipeline", and in any case it will not have been possible to burn all the fossil fuels yet. If Caldeira actually believes it is possible to burn ALL the fossil fuels and have the average middle class person in developed countries not feel the consequences very strongly, how is it that apparently, so many of his colleagues disagree with him?

I'd like to know where I've gone wrong in my effort to understand what scientists believe.

Consider the publicly expressed views of John Schellnhuber of PIK, who stood before the audience at the 4 degrees conference held in Australia and after telling them their Great Barrier Reef was doomed even if civilization managed what seems now to be the almost impossible goal of limiting global warming to 2 degrees C, asked them if very many of them play Russian Roulette at home. He then explained that even if civilization limited global warming to 2 degrees the odds were worse than 1 in 6 that tipping points would be passed anyway which would threaten the existence of civilization.

Perhaps Caldeira assumes geoengineering research has reached a point where he can assume it will be employed, and the planet can be successfully cooled no matter if all the fossil fuels are burned, and that civilization can survive relatively unscathed as the biosphere is disrupted wholesale in the high CO2 artificially cooled world?

Is Kevin Anderson of the Tyndall Centre, who says there is "a widespread view" among top flight scientists he is in contact with that a mere 4 degrees C warming will prove to be "incompatible with an organized global community" and have a "high probability of not being stable", aware of Caldeira's views?




On Tuesday, August 14, 2012 3:22:07 PM UTC-7, andrewjlockley wrote:

CarnegieGlobEcology just uploaded a video:

The Great Climate Experiment: How far can we push the planet? Ken Caldeira [Scientific American]
Ken Caldeira discussing his article in the August 2012 issue of Scientific American.

The article is titled "The Great Climate Experiment. How far can we push the planet?" It extends from page 78 to page 83.

http://dge.stanford.edu/labs/caldeiralab/
http://www.scientificamerican.com/sciammag/ more
user by visiting My Subscriptions.

© 2012 YouTube, LLC
901 Cherry Ave, San Bruno, CA 94066

--
You received this message because you are subscribed to the Google Groups "geoengineering" group.
To view this discussion on the web visit https://groups.google.com/d/msg/geoengineering/-/WNHPgLBYuz8J.

To post to this group, send email to geoengi...@googlegroups.com<mailto:geoengi...@googlegroups.com>.
To unsubscribe from this group, send email to geoengineerin...@googlegroups.com<mailto:geoengineering%2Bunsu...@googlegroups.com>.

For more options, visit this group at http://groups.google.com/group/geoengineering?hl=en.


--
You received this message because you are subscribed to the Google Groups "geoengineering" group.

To post to this group, send email to geoengi...@googlegroups.com<mailto:geoengi...@googlegroups.com>.
To unsubscribe from this group, send email to geoengineerin...@googlegroups.com<mailto:geoengineering%2Bunsu...@googlegroups.com>.

[Andrew Lockley]

There's a good summary on what may happen in an extreme warming/anoxic
event at http://en.wikipedia.org/wiki/Permian%E2%80%93Triassic_extinction_event

Some notable features:
1) Catastrophic loss of calcifying marine organisms, due to ocean acidification
2) Coal gap - indicating that draw down of carbon from the atmosphere
may be affected long-term by the loss of one operating sink
3) 2/3 loss of terrestrial mammal families (not species)
4) CO2 direct toxicity to many animals
5) Destruction of ozone layer, leading to very high UV levels.

My concern is that we can't confidently demonstrate this is about to
happen again. If we don't suffer such a catastrophic destabilisation
of the biosphere, I agree with Ken that there could be a
civilisation-survivable situation in a moderate to high-warming
climate (although I think it more likely that civilisation will
collapse). However, that kind of biosphere destabilisation is what I
think we can expect - principally because of the rate of change of
climate, not the absolute levels of CO2. I think we'd potentially be
looking at human extinction. If we don't have a technological
civilisation left, then any biosphere perturbations that we cannot
individually survive (high UV, high H2S, etc.) will simply kill
everybody. It's this threat which we should be focussed on managing.

A