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.--I¹d 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" <[email protected]> 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 [email protected] > 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 <[email protected]> > 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 >> >> On Aug 15, 2012 11:53 PM, "Ken Caldeira" <[email protected]> >> wrote: >>> 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 water¹s 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 we¹re going to deal with? And I think we can say >>> with a pretty high degree of certainty that it¹s 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 there¹s a few things. One is that, >>> obviously, if you¹re a poor subsistence community depending on coral reefs, >>> you¹re probably in trouble. Maybe also if you¹re a similar subsistence >>> society depending on growing food in a place where you¹re going to have big >>> droughts that you¹re 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 they¹ll still have their TV sets and their >>> McBurgers and McNuggets to eat and that life will go on. >>> >>> That said, we don¹t really know that that¹s 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, there¹s >>> 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 don¹t really know the answers to these questions. We know >>> that our continued emissions of CO2 is increasing our levels of >>> environmental risk, but it¹s really hard to quantify exactly how much risk >>> we¹re 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 <tel:%2B1%20650%20704%207212> [email protected] >>> 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 <[email protected]> >>> 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/51bd >>>> d45979ce24a3/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 >>>>> 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 post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/geoengineering?hl=en.
