I bring to your attention the following: the latest Lindzen paper http://www.drroyspencer.com/Lindzen-and-Choi-GRL-2009.pdf Be warned this is tough.
A simple to understand over review is: Climate Sensitivity Estimates: Heading Down, Way Down? (Richard Lindzen's New Paper) by Chip Knappenberger Using the same climate science; (I am ultra kind to call it science, it is not yet mature enough) Lindzen concludes that Hansen et al estimate a sensitivity that is almost 10X too large; Lindzen claims a delta of +0.5 C for CO2 concentration doubling. You are all intelligent fair human beings, but you carry your biases on your sleeves. Would you bet your reputation or your retirement funds on either of these gentlemen being right. I doubt it. I suggest you all might temper the discussion here with a grain of uncertainty. However, I also understand that if Lindzen is right, geoengineering becomes of virtually no importance. -----Original Message----- From: geoengineering@googlegroups.com [mailto:geoengineer...@googlegroups.com] On Behalf Of John Gorman Sent: Sunday, November 01, 2009 12:34 PM To: j...@cloudworld.co.uk; dan.wha...@gmail.com Cc: geoengineering Subject: [geo] Re: Jamais Cascio-- on the problematic idea of 350 I think the point is as follows: If we fix the CO2 at say 2 times preindustrial then the net forcing will not instantly get the global temperatures up to their long term steady state. The oceans will lag. It sounds as if you are thinking of the net forcing which has resulted in the temperature rise for the land has gone away-but it hasn't in the case you have quoted. The CO2 level will stay constant for centuries even if all emissions stop today. There was a very recent post or link on this recently which quoted 3deg for doubling of CO2 in the short term but 6deg long term. This link, which I cant find just now, used data from some much earlier time when the doubling had already resulted in almost completely ice free poles. This is presumably what will happen now if we get to doubling and don't do something about it. The Arctic is melting now. It isn't going to stop melting just because we stop increasing the temperature. So there is a temperature inertia or lag due to ocean heat capacity but an even bigger one due to ice cap latent heat of melting. john gorman ----- Original Message ----- From: "John Nissen" <j...@cloudworld.co.uk> To: <dan.wha...@gmail.com> Cc: "geoengineering" <geoengineering@googlegroups.com> Sent: Sunday, November 01, 2009 1:56 PM Subject: [geo] Re: Jamais Cascio-- on the problematic idea of 350 > > > Hi all, > > Jamais Cascio is described as an "environmental futurist" and has > written a book with the title "Hacking the Earth" [1]. It's great that > somebody is pointing out the implication of the 350 ppm target! > > But he shares a very common scientific belief which I do not understand: > > "(Even more troubling: even if we stopped all anthropogenic carbon > sources immediately, we'd still see continued warming for at least > decades, possibly longer, simply from the thermal inertia of the > oceans. Absent a radical step, we're guaranteed to see at least > another degree or two of warming, no matter what we do.)" > > > With global warming, the land and atmosphere warm faster than the > oceans. If emissions stopped overnight, the oceans would still be > warming up, thus cooling the atmosphere, rather than warming it. Thus > the thermal inertia of the oceans would drag down the global temperature > (mean of surface temperatures over the globe). Am I right? > > Cheers, > > John > > [1] http://www.lulu.com/content/6048806 > > -- > > Dan Whaley wrote: >> You will appreciate this one Greg... >> >> http://www.fastcompany.com/blog/jamais-cascio/open-future/350 >> >> 350 >> BY Jamais CascioTue Oct 27, 2009 at 2:55 PM >> 350 parts-per-million is the carbon limit. How will we get back there? >> >> 350.org >> >> It may be odd to focus a political movement on a relatively obscure >> bit of science, but a world-wide push to limit concentration of >> atmospheric carbon dioxide to 350 parts-per-million made a big splash >> last week, with rallies and gatherings all over the planet focusing on >> drilling this number into the public consciousness. The number comes >> from work done by (among others) NASA's James Hansen, looking for >> potential climate "tipping points." 350ppm for CO2 is a safe limit-- >> get too much beyond it, and the dangers multiply. >> >> It's an audacious goal, for reasons of both communication and science. >> >> In terms of communication, while a simple meme like "350" or "350ppm" >> fits nicely on protest signs and bumper stickers, it's a term without >> much context for the vast majority of the populace. In and of itself, >> that's not a problem; however, it can make a visceral connection to >> the concept more difficult. Activists adopting the 350 meme will need >> to match rhetoric with education, to make the number meaningful. >> Again, not impossible, but likely an ongoing challenge. >> >> The scientific audacity with the 350 meme comes from a single, simple >> fact: current concentration of atmospheric CO2 is roughly 385ppm. That >> is, we already exceed the 350 limit, and most climate scientists say >> we'll be hard-pressed to keep from going over 450ppm by the middle of >> the century. And carbon dioxide takes centuries to cycle out of the >> atmosphere--even if we stopped all anthropogenic sources of CO2 right >> this minute, we'd still see too-high concentrations for years to come. >> >> (Even more troubling: even if we stopped all anthropogenic carbon >> sources immediately, we'd still see continued warming for at least >> decades, possibly longer, simply from the thermal inertia of the >> oceans. Absent a radical step, we're guaranteed to see at least >> another degree or two of warming, no matter what we do.) >> >> If this sounds like I think the 350 movement is a bad idea... I don't. >> I rather like the simplicity of the meme, and the target is--if >> difficult--smart. It's not saying "let's keep things from getting too >> much worse," it's saying "let's make things better." That's the kind >> of goal I like. >> >> But getting back to 350ppm requires more than a rapid cessation of >> anthropogenic sources of atmospheric carbon. It requires an >> acceleration of the processes that cycle atmospheric CO2. Planting >> trees is an obvious step, but it's slow and actually doesn't do enough >> alone. We'll also need to bring in more advanced carbon sequestration >> techniques, such as bio-char. The combination of the two would likely >> bring down atmospheric carbon levels, given enough time. >> >> Unfortunately, we may not have enough time. >> >> If efforts to eliminate carbon emissions continue to happen at a pace >> most generously described as "leisurely," we will almost certainly >> face a situation where we approach and even pass critical tipping >> point concentrations. Ocean thermal inertia means that climate >> benefits from emission cessation won't be seen for decades. There's a >> very real scenario where finally get it right, both cutting out >> anthropogenic emissions and sequestering megatons of carbon via plants >> and bio-char ... and still face terrible environmental consequences, >> simply because we didn't act fast enough. >> >> That's where we start to talk about much more radical, and potentially >> dangerous, steps. Geoengineering to hold temperatures down is one; to >> meet the 350ppm goal, we will likely also start looking at large-scale >> methods to sequester carbon, such as with triggered algae blooms. >> >> 350ppm is an audacious goal, but one worth striving for. But its >> challenge comes not just in the effort to eliminate anthropogenic >> carbon emissions around the world--a massive endeavor alone--but also >> in figuring out how to remove the extra carbon already there. I hope >> that the 350 leaders have thought through the implications of what >> that means. >> >> [Images: "Organized Spelling B" by Wade in Da Water on Flickr, >> Creative Commons Licensed; "Summer Bloom in the Baltic Sea" by NASA >> Visible Earth] >> > >> > > > > --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "geoengineering" group. To post to this group, send email to geoengineering@googlegroups.com To unsubscribe from this group, send email to geoengineering+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/geoengineering?hl=en -~----------~----~----~----~------~----~------~--~---
