Re: [geo] Background-Greenland collapse
Geo and cc Jasmin I have sent this message (and added a bit) over to the CDR list. Ron > On Aug 15, 2020, at 5:54 PM, Jasmin S. A. Link > wrote: > > Dear Ron, > > Thank you very much, for your interest an for emphasizing the relevance of my > thesis in the context of SRM and CDR. > > Please, feel free to add me to the CDR list as well. > > The detailed potential side effects networks I have published only for SAI > (Figure 3.1.) and BECCS (Figure 3.2. in the same EuTRACE final report) so > far. I have made one for afforestion, but that has not been as requested and > intriguing for discussion yet. > > I think, some of the potential indirect side effects of SRM - such as a > potential reduction in individual mitigation efforts - might also apply to a > large-scale CDR. Depending on the method of CDR and its public presence (like > artificial trees), this might also be true for even relatively small > applications of CDR. Thus, it might be important to estimate in advance, if > the contruction of one artifical tree rather decreases carbon emissions, by > capturing them, or in total rather increases carbon emissions, by triggering > passengers to feel free to emit more carbon. > > Best regards, > > Jasmin > > > > Am 15.08.2020 um 19:47 schrieb Ronal Larson: >> Dr. Link and list: -- You received this message because you are subscribed to the Google Groups "geoengineering" group. To unsubscribe from this group and stop receiving emails from it, send an email to geoengineering+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/geoengineering/34C2E2CB-DAC8-4850-8ECA-4ABBEA62208E%40comcast.net.
RE: [geo] Background-Greenland collapse
Certainly the term moral hazard as used in other literature doesn’t imply any conscious thought process as a requirement. (Examples might be better termed risk compensation; someone is more likely to drive close to a cyclist who is wearing a helmet, for example.) Perhaps better to simply use the term mitigation deterrence and not make any implied judgment. From: geoengineering@googlegroups.com On Behalf Of Andrew Lockley Sent: Sunday, August 16, 2020 11:24 AM To: Jasmin S. A. Link Cc: geoengineering Subject: Re: [geo] Background-Greenland collapse To clarify, morale hazard is lazy recklessness (I'll put off swapping my SUV for a tesla, because geoengineering may sort it out) moral hazard is manipulative (I'll dangle the carrot of geoengineering, to get approval for keystone). Personal profit is inherent in moral hazard, knowingly harming others. Sorry if this is wandering off topic. On Sun, 16 Aug 2020, 16:15 Jasmin S. A. Link, mailto:jasmin.l...@uni-hamburg.de>> wrote: Yes. I am not sure, whether moral hazard or even morale hazard, as Andrew has pointed out, exactly name what I try to describe. Moral hazard or morale hazard seem to me both have at least a deliberate decision, at least concious, perhaps even rational or optimizing in some sense, of action making in common. Regarding emission behavior, people usually do not deliberately choose to emit CO2 directly or indirectly. Usally, the emissions are just a side-effect of their consumption, their way of living. Thus, a side-effect of their routines. For many people it is even difficult to reflect on how much carbon they emit via which choice of consumption. Consequently, an individual attempt to reduce carbon emissions is a great effort and usually a large step out of the comfort zone for a single person. Calling it moral hazard, if they "just relax" and fall back a bit in their routines, or enjoy intensifying them, sounds a bit hard. This kind of behavioral decision-making processes may be far from what you might expect as rational decision-making. In my earlier referred thesis (Link 2018) I coin the term "path-dependent behavior", which is the result of the influence of existing path-dependent processes and is rather a following behavior, following routines/standards/institutions, the masses, neighbors etc. It is an efficient way of decision-making, resulting from a short-cut in the brain (applying the least-effort-principle from social psychology). But the resulting action may be a different one than the result of a utility function would be. Like following the advice of your computer expert (Herbert Simon has also described the phenomenon of personal experts) does not mean that you have optimized the variety of choices yourself. But if the choice you have made that way is producing more carbon emissions along the way than a different one would have, that you might have not even thought about when only relying on your personal expert: Can you be accused for moral(e) hazard? Best regards, Jasmin Am 16.08.2020 um 12:59 schrieb Douglas MacMartin: Thanks – I agree completely that moral hazard is a serious risk, perhaps the biggest risk. (But I also think it is important to be more explicit about one’s assumptions.) There’ve been a few studies trying to look at moral hazard, with inconclusive results even on the sign of the effect – very hard to make predictions about, but, of course, very clear that it is a serious possibility. (And re acid rain, that’s not significant in terms of ocean acidification.) doug From: Jasmin S. A. Link <mailto:jasmin.l...@uni-hamburg.de> Sent: Saturday, August 15, 2020 7:32 PM To: Douglas MacMartin <mailto:dgm...@cornell.edu>; geoengineering@googlegroups.com<mailto:geoengineering@googlegroups.com> Subject: Re: [geo] Background-Greenland collapse Thank you Doug, > If you would plan the potential deployment of SRM (especially on a > large-scale) you would in the same way have to consider the potential side > effects beforehand to assure to decouple a deployment of SRM from these > potential side effects. Otherwise you would risk the accumulation in > acidification of the oceans, self-reinforcing the reduction in biodiversity, > loss in coral reefs, accumulating in social tensions (just to name a few of > the interconnected potential side effects, cp. Figure 3.1.,p.71 in the > transdisciplinary network of potential side effects in: > https://www.iass-potsdam.de/sites/default/files/2018-06/EuTRACE_report_digital_second_edition.pdf > ). < Regarding ocean acidification and acid rain: Yes, putting up mirrors would not directly cause ocean acidification but SAI might cause acid rain (depending on the aerosol used). And no, it still is related via an indirect effect in terms of social behavior: If people comprehend SRM in a way as that there is some sort of technical
Re: [geo] Background-Greenland collapse
lso shows that it is
possible to get ~5m of SLR in a single century, but that’s coming
out of the last glacial when there was a lot more available to be
melted, and that doesn’t say that it is possible to get anything
close to that this century.)
-Arguably this is simply quibbling over whether we can prove we’re
past the point where even aggressive CDR would work, or whether
there’s simply a risk that we’re past that point, in which case
arguing over whether that is 20% or 50% or 10% might not matter
for policy. I do agree that we are gambling with the climate, and
with odds that no-one would accept in any other circumstance.
-Personally, given how little research has been done, I don’t
think there’s strong justification for saying that the long-term
climate consequences of waiting another 10-15 years for research
(and to develop governance capacity) will be so bad that we should
go ahead and deploy something now without doing the research
(though if we did deploy something now, I’d worry more about the
societal response than the physical issues). But, just like the
US didn’t use the first few months of this year to prepare for
covid when it knew it was coming, it would be truly awful to not
do the research now, leaving us in the same boat yet another
decade later.
doug
*From:*Michael MacCracken mailto:mmacc...@comcast.net>>
*Sent:* Saturday, August 15, 2020 12:54 PM
*To:* Douglas MacMartin mailto:dgm...@cornell.edu>>; andrew.lock...@gmail.com
<mailto:andrew.lock...@gmail.com>; geoengineering
mailto:geoengineering@googlegroups.com>>
*Subject:* Re: [geo] Background-Greenland collapse
Hi Doug et al.--I'm a bit late to this particular conversation,
but I am astonished by the suggestion that Greenland can only
cause such a small potential rate of rise in sea level. There was
just a kerfuffle with the IPCC authors on their draft projections
of rates (see attached letter). While surface melt rate may be
relatively slow as often calculated, it is not the main loss of
mass process--ice stream flow is very likely the major loss rate
once it gets going and the calculations that are done in most
models do not include this term, nor do they include the effects
of ice shelf thinning that is going on. From the peak of the last
interglacial to 8 ka, sea level rose at an average rate of a meter
per century while global average temperature rose at an average
rate of a degree C per 2000 years, and the CO2 concentration was
less than 300 ppm. The documentary "Chasing Ice" shows how fast
ice can disappear, and not just in the ice stream calving that is
the most amazing aspect of that film. And paleo evidence also
makes very clear that ice sheets go away much faster than they
build up.
And the question is not so much when the cities will be under
water as when it will become inevitable that they will be under
water--given that consideration and the paleo sensitivity being
something like 15-20 meters per degree C warming (and this is not
just me saying this, but see Eric Rignot talk to the NAS last
year--see https://vimeo.com/332486918 <https://vimeo.com/332486918> ).
Based on this sensitivity, we're already past the point where it
would be good to have climate intervention underway if we want to
avoid significant and early risk to our cities with a very high
likelihood (and this is the criterion that is often used in
building infrastructure--avoiding 1 in 100 year events or even
rarer ones--consider the Dutch for their levees--1 in 10,000 year
storms).
Mike MacCracken
On 8/15/20 7:03 AM, Douglas MacMartin wrote:
What is not correct in the media report is this sentence:
“This process, however, would take decades.” Well, I guess
arguably that’s true, it’s just it would take a LOT of
decades. Melt rate is currently of order 1-2mm/yr equivalent
SLR, so to get the 6m from melting all of Greenland would take
a few thousand years. Obviously it can speed up a lot, but
“hey, it’s losing mass” does not remotely imply “therefore we
only have a few decades before we lose our coastal cities”.
So no, you can’t use this study to claim that geoengineering
is required to keep our coastal cities. The problem with
relying on mitigation+CDR is time-scale, but this study
doesn’t prove that our response time-scale needs to be faster
than what CDR can (at least hypothetically) provide.
d
*From:*geoengineering@googlegroups.com
<mailto:geoengineering@googlegroups.com>
<mailto:geoengineering@googlegroups.com> *On Behalf Of *Andrew
Lockley
*Sent:* Saturday, August 15, 2020 3:40 AM
*To:* ge
Re: [geo] Background-Greenland collapse
To clarify, morale hazard is lazy recklessness (I'll put off swapping my SUV for a tesla, because geoengineering may sort it out) moral hazard is manipulative (I'll dangle the carrot of geoengineering, to get approval for keystone). Personal profit is inherent in moral hazard, knowingly harming others. Sorry if this is wandering off topic. On Sun, 16 Aug 2020, 16:15 Jasmin S. A. Link, wrote: > Yes. I am not sure, whether moral hazard or even morale hazard, as Andrew > has pointed out, exactly name what I try to describe. Moral hazard or > morale hazard seem to me both have at least a deliberate decision, at least > concious, perhaps even rational or optimizing in some sense, of action > making in common. Regarding emission behavior, people usually do not > deliberately choose to emit CO2 directly or indirectly. Usally, the > emissions are just a side-effect of their consumption, their way of living. > Thus, a side-effect of their routines. For many people it is even difficult > to reflect on how much carbon they emit via which choice of consumption. > Consequently, an individual attempt to reduce carbon emissions is a great > effort and usually a large step out of the comfort zone for a single > person. Calling it moral hazard, if they "just relax" and fall back a bit > in their routines, or enjoy intensifying them, sounds a bit hard. This kind > of behavioral decision-making processes may be far from what you might > expect as rational decision-making. > > In my earlier referred thesis (Link 2018) I coin the term "path-dependent > behavior", which is the result of the influence of existing path-dependent > processes and is rather a following behavior, following > routines/standards/institutions, the masses, neighbors etc. It is an > efficient way of decision-making, resulting from a short-cut in the brain > (applying the least-effort-principle from social psychology). But the > resulting action may be a different one than the result of a utility > function would be. Like following the advice of your computer expert > (Herbert Simon has also described the phenomenon of personal experts) does > not mean that you have optimized the variety of choices yourself. But if > the choice you have made that way is producing more carbon emissions along > the way than a different one would have, that you might have not even > thought about when only relying on your personal expert: Can you be accused > for moral(e) hazard? > > Best regards, > > Jasmin > > > > > > Am 16.08.2020 um 12:59 schrieb Douglas MacMartin: > > Thanks – I agree completely that moral hazard is a serious risk, perhaps > the biggest risk. (But I also think it is important to be more explicit > about one’s assumptions.) > > > > There’ve been a few studies trying to look at moral hazard, with > inconclusive results even on the sign of the effect – very hard to make > predictions about, but, of course, very clear that it is a serious > possibility. > > > > (And re acid rain, that’s not significant in terms of ocean acidification.) > > > > doug > > > > *From:* Jasmin S. A. Link > > *Sent:* Saturday, August 15, 2020 7:32 PM > *To:* Douglas MacMartin ; > geoengineering@googlegroups.com > *Subject:* Re: [geo] Background-Greenland collapse > > > > Thank you Doug, > > > If you would plan the potential deployment of SRM (especially on a > large-scale) you would in the same way have to consider the potential side > effects beforehand to assure to decouple a deployment of SRM from these > potential side effects. Otherwise you would risk the accumulation in > acidification of the oceans, self-reinforcing the reduction in > biodiversity, loss in coral reefs, accumulating in social tensions (just to > name a few of the interconnected potential side effects, cp. Figure > 3.1.,p.71 in the transdisciplinary network of potential side effects in: > https://www.iass-potsdam.de/sites/default/files/2018-06/EuTRACE_report_digital_second_edition.pdf > ). < > > Regarding ocean acidification and acid rain: Yes, putting up mirrors would > not directly cause ocean acidification but SAI might cause acid rain > (depending on the aerosol used). And no, it still is related via an > indirect effect in terms of social behavior: If people comprehend SRM in a > way as that there is some sort of technical compensation happening for > their carbon emissions, they are likely to rather not reduce their own > carbon emissions, but instead increase their own carbon emissions. This is > marked in Figure 3.1. as "less necessity for direct emission reduction?" > connected to a "rise of CO2 emissions", which causes multiple feedbacks > such as the necessi
Re: [geo] Background-Greenland collapse
Whenever this issue comes up, I feel obliged to draw attention to the fact that moral(e) hazard is actually two separate things: recklessness (morale) and malfeasance (moral). https://journals.sagepub.com/doi/abs/10.1177/1461452916659830 On Sun, 16 Aug 2020, 11:59 Douglas MacMartin, wrote: > Thanks – I agree completely that moral hazard is a serious risk, perhaps > the biggest risk. (But I also think it is important to be more explicit > about one’s assumptions.) > > > > There’ve been a few studies trying to look at moral hazard, with > inconclusive results even on the sign of the effect – very hard to make > predictions about, but, of course, very clear that it is a serious > possibility. > > > > (And re acid rain, that’s not significant in terms of ocean acidification.) > > > > doug > > > > *From:* Jasmin S. A. Link > *Sent:* Saturday, August 15, 2020 7:32 PM > *To:* Douglas MacMartin ; > geoengineering@googlegroups.com > *Subject:* Re: [geo] Background-Greenland collapse > > > > Thank you Doug, > > > If you would plan the potential deployment of SRM (especially on a > large-scale) you would in the same way have to consider the potential side > effects beforehand to assure to decouple a deployment of SRM from these > potential side effects. Otherwise you would risk the accumulation in > acidification of the oceans, self-reinforcing the reduction in > biodiversity, loss in coral reefs, accumulating in social tensions (just to > name a few of the interconnected potential side effects, cp. Figure > 3.1.,p.71 in the transdisciplinary network of potential side effects in: > https://www.iass-potsdam.de/sites/default/files/2018-06/EuTRACE_report_digital_second_edition.pdf > ). < > > Regarding ocean acidification and acid rain: Yes, putting up mirrors would > not directly cause ocean acidification but SAI might cause acid rain > (depending on the aerosol used). And no, it still is related via an > indirect effect in terms of social behavior: If people comprehend SRM in a > way as that there is some sort of technical compensation happening for > their carbon emissions, they are likely to rather not reduce their own > carbon emissions, but instead increase their own carbon emissions. This is > marked in Figure 3.1. as "less necessity for direct emission reduction?" > connected to a "rise of CO2 emissions", which causes multiple feedbacks > such as the necessity to further increase the SAI deployment. I think, > there have been more recent simulation studies at MIT on this kind of > behavior that support the relevance of this potential indirect effect. > > In my argument on the potential accumulation in acidification of the > oceans, I had this indirect effect of the SRM deployment on the rather > increased carbon emission behavior in mind: Officially applying a method to > reduce global warming which might be understood as "fixing the problem with > engineering" might rather reduce than increase individual mitigation > efforts. (Of course, we know that the problem is not really fixed, but try > to explain that to usual consumers who would know at some point that their > government would regularly spend large sums of money on SRM and who might > feel more comfortable to stick and increase their former behavior than to > really change it, due to path dependence). > > Best, > > Jasmin > > > > Am 15.08.2020 um 23:40 schrieb Douglas MacMartin: > > Thanks Jasmin, > > > > Agree that all the side effects of SRM need to be considered, and need to > evaluate options holistically. > > > > That said, SRM does not cause ocean acidification; CO2 causes ocean > acidification. So one should never list ocean acidification as a side > effect. (It is true that SRM doesn’t solve ocean acidification, but it > also doesn’t solve car accidents… and no-one lists that as a reason not to > consider SRM.) Implicit in listing acidification in any discussion of SRM > is an assumption that somehow we’re required to choose between reducing CO2 > or using SRM, in much the same way that we have to choose whether to drive > safely or wear a seat belt, but we’re not allowed to do both. > > > > doug > > > > *From:* geoengineering@googlegroups.com > *On Behalf Of *Jasmin S. A. Link > *Sent:* Saturday, August 15, 2020 8:32 AM > *To:* geoengineering@googlegroups.com > *Subject:* Re: [geo] Background-Greenland collapse > > > > "The more advanced the process, the more momentum it has, and the harder > it is to stop or reverse." The same can count for social dynamics. > Self-reinforcing processes with the tendency towards a lock-in are > path-dependent processes. That is, wh
RE: [geo] Background-Greenland collapse
Thanks – I agree completely that moral hazard is a serious risk, perhaps the biggest risk. (But I also think it is important to be more explicit about one’s assumptions.) There’ve been a few studies trying to look at moral hazard, with inconclusive results even on the sign of the effect – very hard to make predictions about, but, of course, very clear that it is a serious possibility. (And re acid rain, that’s not significant in terms of ocean acidification.) doug From: Jasmin S. A. Link Sent: Saturday, August 15, 2020 7:32 PM To: Douglas MacMartin ; geoengineering@googlegroups.com Subject: Re: [geo] Background-Greenland collapse Thank you Doug, > If you would plan the potential deployment of SRM (especially on a > large-scale) you would in the same way have to consider the potential side > effects beforehand to assure to decouple a deployment of SRM from these > potential side effects. Otherwise you would risk the accumulation in > acidification of the oceans, self-reinforcing the reduction in biodiversity, > loss in coral reefs, accumulating in social tensions (just to name a few of > the interconnected potential side effects, cp. Figure 3.1.,p.71 in the > transdisciplinary network of potential side effects in: > https://www.iass-potsdam.de/sites/default/files/2018-06/EuTRACE_report_digital_second_edition.pdf > ). < Regarding ocean acidification and acid rain: Yes, putting up mirrors would not directly cause ocean acidification but SAI might cause acid rain (depending on the aerosol used). And no, it still is related via an indirect effect in terms of social behavior: If people comprehend SRM in a way as that there is some sort of technical compensation happening for their carbon emissions, they are likely to rather not reduce their own carbon emissions, but instead increase their own carbon emissions. This is marked in Figure 3.1. as "less necessity for direct emission reduction?" connected to a "rise of CO2 emissions", which causes multiple feedbacks such as the necessity to further increase the SAI deployment. I think, there have been more recent simulation studies at MIT on this kind of behavior that support the relevance of this potential indirect effect. In my argument on the potential accumulation in acidification of the oceans, I had this indirect effect of the SRM deployment on the rather increased carbon emission behavior in mind: Officially applying a method to reduce global warming which might be understood as "fixing the problem with engineering" might rather reduce than increase individual mitigation efforts. (Of course, we know that the problem is not really fixed, but try to explain that to usual consumers who would know at some point that their government would regularly spend large sums of money on SRM and who might feel more comfortable to stick and increase their former behavior than to really change it, due to path dependence). Best, Jasmin Am 15.08.2020 um 23:40 schrieb Douglas MacMartin: Thanks Jasmin, Agree that all the side effects of SRM need to be considered, and need to evaluate options holistically. That said, SRM does not cause ocean acidification; CO2 causes ocean acidification. So one should never list ocean acidification as a side effect. (It is true that SRM doesn’t solve ocean acidification, but it also doesn’t solve car accidents… and no-one lists that as a reason not to consider SRM.) Implicit in listing acidification in any discussion of SRM is an assumption that somehow we’re required to choose between reducing CO2 or using SRM, in much the same way that we have to choose whether to drive safely or wear a seat belt, but we’re not allowed to do both. doug From: geoengineering@googlegroups.com<mailto:geoengineering@googlegroups.com> <mailto:geoengineering@googlegroups.com> On Behalf Of Jasmin S. A. Link Sent: Saturday, August 15, 2020 8:32 AM To: geoengineering@googlegroups.com<mailto:geoengineering@googlegroups.com> Subject: Re: [geo] Background-Greenland collapse "The more advanced the process, the more momentum it has, and the harder it is to stop or reverse." The same can count for social dynamics. Self-reinforcing processes with the tendency towards a lock-in are path-dependent processes. That is, why it is not easy to just change carbon intensive behavior towards low carbon emission behavior. Many social, economical, and technical processes have the production of carbon emissions as side effects which accumulate during the intensifying self-reinforcing processes (cp. Figure 4 p. 63 in https://ediss.sub.uni-hamburg.de/volltexte/2020/10431/pdf/Dissertation.pdf ). But what about the side effects of SRM that would accumulate over time while deployment in an intensity of "driving the earth into a glacial period"? It is necessary to decouple self-reinforcing processes from producing carbon
Re: [geo] Background-Greenland collapse
Thank you Doug, > If you would plan the potential deployment of SRM (especially on a large-scale) you would in the same way have to consider the potential side effects beforehand to assure to decouple a deployment of SRM from these potential side effects. Otherwise you would risk the accumulation in acidification of the oceans, self-reinforcing the reduction in biodiversity, loss in coral reefs, accumulating in social tensions (just to name a few of the interconnected potential side effects, cp. Figure 3.1.,p.71 in the transdisciplinary network of potential side effects in: https://www.iass-potsdam.de/sites/default/files/2018-06/EuTRACE_report_digital_second_edition.pdf ). < Regarding ocean acidification and acid rain: Yes, putting up mirrors would not directly cause ocean acidification but SAI might cause acid rain (depending on the aerosol used). And no, it still is related via an indirect effect in terms of social behavior: If people comprehend SRM in a way as that there is some sort of technical compensation happening for their carbon emissions, they are likely to rather not reduce their own carbon emissions, but instead increase their own carbon emissions. This is marked in Figure 3.1. as "less necessity for direct emission reduction?" connected to a "rise of CO2 emissions", which causes multiple feedbacks such as the necessity to further increase the SAI deployment. I think, there have been more recent simulation studies at MIT on this kind of behavior that support the relevance of this potential indirect effect. In my argument on the potential accumulation in acidification of the oceans, I had this indirect effect of the SRM deployment on the rather increased carbon emission behavior in mind: Officially applying a method to reduce global warming which might be understood as "fixing the problem with engineering" might rather reduce than increase individual mitigation efforts. (Of course, we know that the problem is not really fixed, but try to explain that to usual consumers who would know at some point that their government would regularly spend large sums of money on SRM and who might feel more comfortable to stick and increase their former behavior than to really change it, due to path dependence). Best, Jasmin Am 15.08.2020 um 23:40 schrieb Douglas MacMartin: Thanks Jasmin, Agree that all the side effects of SRM need to be considered, and need to evaluate options holistically. That said, SRM does not cause ocean acidification; CO2 causes ocean acidification. So one should never list ocean acidification as a side effect. (It is true that SRM doesn’t solve ocean acidification, but it also doesn’t solve car accidents… and no-one lists that as a reason not to consider SRM.) Implicit in listing acidification in any discussion of SRM is an assumption that somehow we’re required to choose between reducing CO2 or using SRM, in much the same way that we have to choose whether to drive safely or wear a seat belt, but we’re not allowed to do both. doug *From:*geoengineering@googlegroups.com *On Behalf Of *Jasmin S. A. Link *Sent:* Saturday, August 15, 2020 8:32 AM *To:* geoengineering@googlegroups.com *Subject:* Re: [geo] Background-Greenland collapse "The more advanced the process, the more momentum it has, and the harder it is to stop or reverse." The same can count for social dynamics. Self-reinforcing processes with the tendency towards a lock-in are path-dependent processes. That is, why it is not easy to just change carbon intensive behavior towards low carbon emission behavior. Many social, economical, and technical processes have the production of carbon emissions as side effects which accumulate during the intensifying self-reinforcing processes (cp. Figure 4 p. 63 in https://ediss.sub.uni-hamburg.de/volltexte/2020/10431/pdf/Dissertation.pdf ). But what about the side effects of SRM that would accumulate over time while deployment in an intensity of "driving the earth into a glacial period"? It is necessary to decouple self-reinforcing processes from producing carbon emissions as a side effect. And try to potentially include the reduction of carbon emissions as side effects of new self-reinforcing processes that show the dynamic of "the more advanced the process, the more momentum it has, and the harder it is to stop or reverse". If you would plan the potential deployment of SRM (especially on a large-scale) you would in the same way have to consider the potential side effects beforehand to assure to decouple a deployment of SRM from these potential side effects. Otherwise you would risk the accumulation in acidification of the oceans, self-reinforcing the reduction in biodiversity, loss in coral reefs, accumulating in social tensions (just to name a few of the interconnected potential side effects, cp. Figure 3.1.,p.71 in the transdis
Re: [geo] Background-Greenland collapse
Doug, If it where only the Greenland ice sheet that was suffering catastrophic and irreversible change, we might be able to relax and wait 10 to 15 years, but every part of the world and all it's ecosystems are facing similar destructive change, from the coral reefs to the subsea permafrost. This is happening as the global population is heading towards 10 billion with almost everyone already at each throats. If we delay SRM then the scale of the necessary intervention will grow with the delay, most likely exponentially, and the risks of unintended consequences or out right failure will grow accordingly. At the same time, society could be at a point of break down making any coordinated plan virtually impossible and debates about agreeing on global governance irrelevant. Maybe some elements of the paper that was posted can be quibbled over, but the need to make an urgent start on SRM can't be. Kevin On Sat, 15 Aug 2020, 22:35 Douglas MacMartin, wrote: > Hi Mike, > > > > - I don’t know (and I’m not sure anyone really does) how much > Greenland ice sheet mass loss can accelerate, but agree that it won’t stay > at the current rate. > > - Mainly my point was that the media link Andrew sent was silly > by implying that the 6m could happen in decades (even if it didn’t > technically say that), and the paper doesn’t make any claims about how much > the loss rate will accelerate… and to support the claim that geoengineering > is the **ONLY** way to avoid catastrophic sea level rise requires > evidence that we need to intervene now rather than over the rest of the > century. I do agree that there’s good reason to suspect that Andrew’s > claim may be true, but it is certainly not supported by the paper he was > referring to, and I don’t think we can prove that the claim is true. > > - Paleo evidence makes it clear that staying at even the current > CO2 levels for millennia would be catastrophic. It doesn’t do a great job > of constraining how rapidly we need to change, e.g. if CDR over the rest of > the century would also be an adequate alternative to SRM. (And paleo > evidence also shows that it is possible to get ~5m of SLR in a single > century, but that’s coming out of the last glacial when there was a lot > more available to be melted, and that doesn’t say that it is possible to > get anything close to that this century.) > > - Arguably this is simply quibbling over whether we can prove > we’re past the point where even aggressive CDR would work, or whether > there’s simply a risk that we’re past that point, in which case arguing > over whether that is 20% or 50% or 10% might not matter for policy. I do > agree that we are gambling with the climate, and with odds that no-one > would accept in any other circumstance. > > - Personally, given how little research has been done, I don’t > think there’s strong justification for saying that the long-term climate > consequences of waiting another 10-15 years for research (and to develop > governance capacity) will be so bad that we should go ahead and deploy > something now without doing the research (though if we did deploy something > now, I’d worry more about the societal response than the physical issues). > But, just like the US didn’t use the first few months of this year to > prepare for covid when it knew it was coming, it would be truly awful to > not do the research now, leaving us in the same boat yet another decade > later. > > doug > > > > *From:* Michael MacCracken > *Sent:* Saturday, August 15, 2020 12:54 PM > *To:* Douglas MacMartin ; andrew.lock...@gmail.com; > geoengineering > *Subject:* Re: [geo] Background-Greenland collapse > > > > Hi Doug et al.--I'm a bit late to this particular conversation, but I am > astonished by the suggestion that Greenland can only cause such a small > potential rate of rise in sea level. There was just a kerfuffle with the > IPCC authors on their draft projections of rates (see attached letter). > While surface melt rate may be relatively slow as often calculated, it is > not the main loss of mass process--ice stream flow is very likely the major > loss rate once it gets going and the calculations that are done in most > models do not include this term, nor do they include the effects of ice > shelf thinning that is going on. From the peak of the last interglacial to > 8 ka, sea level rose at an average rate of a meter per century while global > average temperature rose at an average rate of a degree C per 2000 years, > and the CO2 concentration was less than 300 ppm. The documentary "Chasing > Ice" shows how fast ice can disappear, and not just in the ice stream > calving that is the most amazing aspect of that film. And paleo evide
Re: [geo] Background-Greenland collapse
Mike, Douglas thinks: "it is possible that neither of those options would arrest mass loss without cooling beyond preindustrial, and that over the ensuing millennium we would eventually lose our coastal cities no matter what we do, " But it is curious how may former seaports have ended up stranded inland by sediment transport- Troy and Pisa fpr instance.We need to consider how many of "our" major coastal cities existed in recognizable form a hundred, let alone a thousand years ago? Modern demographics have driven the rise of skyscrapers out of former swamps from Miami to Singapore, and experience architectural rollover on a time scale reckoned in generations, not centuries. Coastal plains may be doomed, but San Francisco and Hong Kong are a ar cry from Houston and Lagos. Has the IPCC mapped and counted the fraction of current coastal city populations that can gain a meter of elevation by walking a kilometer inland from the neighborhoods in which they presently reside? There's more at issue than urban islands like Venice. Cities have a life of their own , and wherever waterfronts can migrate inland, waterfront properties will continue to be built behind them On Saturday, August 15, 2020 at 12:54:14 PM UTC-4 Mike MacCracken wrote: > Hi Doug et al.--I'm a bit late to this particular conversation, but I am > astonished by the suggestion that Greenland can only cause such a small > potential rate of rise in sea level. There was just a kerfuffle with the > IPCC authors on their draft projections of rates (see attached letter). > While surface melt rate may be relatively slow as often calculated, it is > not the main loss of mass process--ice stream flow is very likely the major > loss rate once it gets going and the calculations that are done in most > models do not include this term, nor do they include the effects of ice > shelf thinning that is going on. From the peak of the last interglacial to > 8 ka, sea level rose at an average rate of a meter per century while global > average temperature rose at an average rate of a degree C per 2000 years, > and the CO2 concentration was less than 300 ppm. The documentary "Chasing > Ice" shows how fast ice can disappear, and not just in the ice stream > calving that is the most amazing aspect of that film. And paleo evidence > also makes very clear that ice sheets go away much faster than they build > up. > > And the question is not so much when the cities will be under water as > when it will become inevitable that they will be under water--given that > consideration and the paleo sensitivity being something like 15-20 meters > per degree C warming (and this is not just me saying this, but see Eric > Rignot talk to the NAS last year--see https://vimeo.com/332486918 ). > > Based on this sensitivity, we're already past the point where it would be > good to have climate intervention underway if we want to avoid significant > and early risk to our cities with a very high likelihood (and this is the > criterion that is often used in building infrastructure--avoiding 1 in 100 > year events or even rarer ones--consider the Dutch for their levees--1 in > 10,000 year storms). > > Mike MacCracken > > > > > > > On 8/15/20 7:03 AM, Douglas MacMartin wrote: > > What is not correct in the media report is this sentence: “This process, > however, would take decades.” Well, I guess arguably that’s true, it’s > just it would take a LOT of decades. Melt rate is currently of order > 1-2mm/yr equivalent SLR, so to get the 6m from melting all of Greenland > would take a few thousand years. Obviously it can speed up a lot, but > “hey, it’s losing mass” does not remotely imply “therefore we only have a > few decades before we lose our coastal cities”. So no, you can’t use this > study to claim that geoengineering is required to keep our coastal cities. > The problem with relying on mitigation+CDR is time-scale, but this study > doesn’t prove that our response time-scale needs to be faster than what CDR > can (at least hypothetically) provide. > > d > > *From:* geoengi...@googlegroups.com *On > Behalf Of *Andrew Lockley > *Sent:* Saturday, August 15, 2020 3:40 AM > *To:* geoengineering > *Subject:* [geo] Background-Greenland collapse > > > > If this study is correct https://www.nature.com/articles/s43247-020-0001-2 > > And is correctly reported here > https://mobile.reuters.com/article/amp/idUSKCN25A2X3 > > Then it appears to back up a point that I have been making for a long > time: geoengineering is required, if we are to keep our coastal cities. I > do not see economic or political feasibility for large scale CDR to tackle > historic emissions, and thus the task must fal
RE: [geo] Background-Greenland collapse
Thanks Jasmin, Agree that all the side effects of SRM need to be considered, and need to evaluate options holistically. That said, SRM does not cause ocean acidification; CO2 causes ocean acidification. So one should never list ocean acidification as a side effect. (It is true that SRM doesn’t solve ocean acidification, but it also doesn’t solve car accidents… and no-one lists that as a reason not to consider SRM.) Implicit in listing acidification in any discussion of SRM is an assumption that somehow we’re required to choose between reducing CO2 or using SRM, in much the same way that we have to choose whether to drive safely or wear a seat belt, but we’re not allowed to do both. doug From: geoengineering@googlegroups.com On Behalf Of Jasmin S. A. Link Sent: Saturday, August 15, 2020 8:32 AM To: geoengineering@googlegroups.com Subject: Re: [geo] Background-Greenland collapse "The more advanced the process, the more momentum it has, and the harder it is to stop or reverse." The same can count for social dynamics. Self-reinforcing processes with the tendency towards a lock-in are path-dependent processes. That is, why it is not easy to just change carbon intensive behavior towards low carbon emission behavior. Many social, economical, and technical processes have the production of carbon emissions as side effects which accumulate during the intensifying self-reinforcing processes (cp. Figure 4 p. 63 in https://ediss.sub.uni-hamburg.de/volltexte/2020/10431/pdf/Dissertation.pdf ). But what about the side effects of SRM that would accumulate over time while deployment in an intensity of "driving the earth into a glacial period"? It is necessary to decouple self-reinforcing processes from producing carbon emissions as a side effect. And try to potentially include the reduction of carbon emissions as side effects of new self-reinforcing processes that show the dynamic of "the more advanced the process, the more momentum it has, and the harder it is to stop or reverse". If you would plan the potential deployment of SRM (especially on a large-scale) you would in the same way have to consider the potential side effects beforehand to assure to decouple a deployment of SRM from these potential side effects. Otherwise you would risk the accumulation in acidification of the oceans, self-reinforcing the reduction in biodiversity, loss in coral reefs, accumulating in social tensions (just to name a few of the interconnected potential side effects, cp. Figure 3.1.,p.71 in the transdisciplinary network of potential side effects in: https://www.iass-potsdam.de/sites/default/files/2018-06/EuTRACE_report_digital_second_edition.pdf ). Furthermore, with SRM you address the global mean temperature. If this would work at all, this would not imply the globally even reduction of temperature, regional effects may differ a lot, potentially increasing also the climate related risks for coastal cities, which you have mentioned as your main concern to safe. Best, Jasmin Am 15.08.2020 um 13:19 schrieb Andrew Lockley: The more advanced the process, the more momentum it has, and the harder it is to stop or reverse. It's unclear whether we could arrest mass loss, without driving the earth into a glacial period (colloquially, an ice age). I don't think there has been any serious modelling work done on ice loss reversal, or even if the models are capable of doing this with any useful accuracy. On Sat, 15 Aug 2020, 12:03 Douglas MacMartin, mailto:dgm...@cornell.edu>> wrote: What is not correct in the media report is this sentence: “This process, however, would take decades.” Well, I guess arguably that’s true, it’s just it would take a LOT of decades. Melt rate is currently of order 1-2mm/yr equivalent SLR, so to get the 6m from melting all of Greenland would take a few thousand years. Obviously it can speed up a lot, but “hey, it’s losing mass” does not remotely imply “therefore we only have a few decades before we lose our coastal cities”. So no, you can’t use this study to claim that geoengineering is required to keep our coastal cities. The problem with relying on mitigation+CDR is time-scale, but this study doesn’t prove that our response time-scale needs to be faster than what CDR can (at least hypothetically) provide. d From: geoengineering@googlegroups.com<mailto:geoengineering@googlegroups.com> mailto:geoengineering@googlegroups.com>> On Behalf Of Andrew Lockley Sent: Saturday, August 15, 2020 3:40 AM To: geoengineering mailto:geoengineering@googlegroups.com>> Subject: [geo] Background-Greenland collapse If this study is correct https://www.nature.com/articles/s43247-020-0001-2 And is correctly reported here https://mobile.reuters.com/article/amp/idUSKCN25A2X3 Then it appears to back up a point that I have been making for a long time: geoengineering is required, if we are to keep our coastal c
RE: [geo] Background-Greenland collapse
Hi Mike, - I don’t know (and I’m not sure anyone really does) how much Greenland ice sheet mass loss can accelerate, but agree that it won’t stay at the current rate. - Mainly my point was that the media link Andrew sent was silly by implying that the 6m could happen in decades (even if it didn’t technically say that), and the paper doesn’t make any claims about how much the loss rate will accelerate… and to support the claim that geoengineering is the *ONLY* way to avoid catastrophic sea level rise requires evidence that we need to intervene now rather than over the rest of the century. I do agree that there’s good reason to suspect that Andrew’s claim may be true, but it is certainly not supported by the paper he was referring to, and I don’t think we can prove that the claim is true. - Paleo evidence makes it clear that staying at even the current CO2 levels for millennia would be catastrophic. It doesn’t do a great job of constraining how rapidly we need to change, e.g. if CDR over the rest of the century would also be an adequate alternative to SRM. (And paleo evidence also shows that it is possible to get ~5m of SLR in a single century, but that’s coming out of the last glacial when there was a lot more available to be melted, and that doesn’t say that it is possible to get anything close to that this century.) - Arguably this is simply quibbling over whether we can prove we’re past the point where even aggressive CDR would work, or whether there’s simply a risk that we’re past that point, in which case arguing over whether that is 20% or 50% or 10% might not matter for policy. I do agree that we are gambling with the climate, and with odds that no-one would accept in any other circumstance. - Personally, given how little research has been done, I don’t think there’s strong justification for saying that the long-term climate consequences of waiting another 10-15 years for research (and to develop governance capacity) will be so bad that we should go ahead and deploy something now without doing the research (though if we did deploy something now, I’d worry more about the societal response than the physical issues). But, just like the US didn’t use the first few months of this year to prepare for covid when it knew it was coming, it would be truly awful to not do the research now, leaving us in the same boat yet another decade later. doug From: Michael MacCracken Sent: Saturday, August 15, 2020 12:54 PM To: Douglas MacMartin ; andrew.lock...@gmail.com; geoengineering Subject: Re: [geo] Background-Greenland collapse Hi Doug et al.--I'm a bit late to this particular conversation, but I am astonished by the suggestion that Greenland can only cause such a small potential rate of rise in sea level. There was just a kerfuffle with the IPCC authors on their draft projections of rates (see attached letter). While surface melt rate may be relatively slow as often calculated, it is not the main loss of mass process--ice stream flow is very likely the major loss rate once it gets going and the calculations that are done in most models do not include this term, nor do they include the effects of ice shelf thinning that is going on. From the peak of the last interglacial to 8 ka, sea level rose at an average rate of a meter per century while global average temperature rose at an average rate of a degree C per 2000 years, and the CO2 concentration was less than 300 ppm. The documentary "Chasing Ice" shows how fast ice can disappear, and not just in the ice stream calving that is the most amazing aspect of that film. And paleo evidence also makes very clear that ice sheets go away much faster than they build up. And the question is not so much when the cities will be under water as when it will become inevitable that they will be under water--given that consideration and the paleo sensitivity being something like 15-20 meters per degree C warming (and this is not just me saying this, but see Eric Rignot talk to the NAS last year--see https://vimeo.com/332486918 ). Based on this sensitivity, we're already past the point where it would be good to have climate intervention underway if we want to avoid significant and early risk to our cities with a very high likelihood (and this is the criterion that is often used in building infrastructure--avoiding 1 in 100 year events or even rarer ones--consider the Dutch for their levees--1 in 10,000 year storms). Mike MacCracken On 8/15/20 7:03 AM, Douglas MacMartin wrote: What is not correct in the media report is this sentence: “This process, however, would take decades.” Well, I guess arguably that’s true, it’s just it would take a LOT of decades. Melt rate is currently of order 1-2mm/yr equivalent SLR, so to get the 6m from melting all of Greenland would take a few thousand years. Obviously it can speed up a lot, but “hey, it’s losing m
Re: [geo] Background-Greenland collapse
Hi Doug et al.--I'm a bit late to this particular conversation, but I am astonished by the suggestion that Greenland can only cause such a small potential rate of rise in sea level. There was just a kerfuffle with the IPCC authors on their draft projections of rates (see attached letter). While surface melt rate may be relatively slow as often calculated, it is not the main loss of mass process--ice stream flow is very likely the major loss rate once it gets going and the calculations that are done in most models do not include this term, nor do they include the effects of ice shelf thinning that is going on. From the peak of the last interglacial to 8 ka, sea level rose at an average rate of a meter per century while global average temperature rose at an average rate of a degree C per 2000 years, and the CO2 concentration was less than 300 ppm. The documentary "Chasing Ice" shows how fast ice can disappear, and not just in the ice stream calving that is the most amazing aspect of that film. And paleo evidence also makes very clear that ice sheets go away much faster than they build up. And the question is not so much when the cities will be under water as when it will become inevitable that they will be under water--given that consideration and the paleo sensitivity being something like 15-20 meters per degree C warming (and this is not just me saying this, but see Eric Rignot talk to the NAS last year--see https://vimeo.com/332486918 ). Based on this sensitivity, we're already past the point where it would be good to have climate intervention underway if we want to avoid significant and early risk to our cities with a very high likelihood (and this is the criterion that is often used in building infrastructure--avoiding 1 in 100 year events or even rarer ones--consider the Dutch for their levees--1 in 10,000 year storms). Mike MacCracken On 8/15/20 7:03 AM, Douglas MacMartin wrote: What is not correct in the media report is this sentence: “This process, however, would take decades.” Well, I guess arguably that’s true, it’s just it would take a LOT of decades. Melt rate is currently of order 1-2mm/yr equivalent SLR, so to get the 6m from melting all of Greenland would take a few thousand years. Obviously it can speed up a lot, but “hey, it’s losing mass” does not remotely imply “therefore we only have a few decades before we lose our coastal cities”. So no, you can’t use this study to claim that geoengineering is required to keep our coastal cities. The problem with relying on mitigation+CDR is time-scale, but this study doesn’t prove that our response time-scale needs to be faster than what CDR can (at least hypothetically) provide. d *From:*geoengineering@googlegroups.com *On Behalf Of *Andrew Lockley *Sent:* Saturday, August 15, 2020 3:40 AM *To:* geoengineering *Subject:* [geo] Background-Greenland collapse If this study is correct https://www.nature.com/articles/s43247-020-0001-2 And is correctly reported here https://mobile.reuters.com/article/amp/idUSKCN25A2X3 Then it appears to back up a point that I have been making for a long time: geoengineering is required, if we are to keep our coastal cities. I do not see economic or political feasibility for large scale CDR to tackle historic emissions, and thus the task must fall to SRM. Nobody has managed to rause an objection to this argument to date. I'd be grateful if those who might disagree were to raise counter arguments now. If the situation is as I understand it, prevarication has no clear benefits, and we should thus move quickly to readiness for deployment. Andrew -- You received this message because you are subscribed to the Google Groups "geoengineering" group. To unsubscribe from this group and stop receiving emails from it, send an email to geoengineering+unsubscr...@googlegroups.com <mailto:geoengineering+unsubscr...@googlegroups.com>. To view this discussion on the web visit https://groups.google.com/d/msgid/geoengineering/CAJ3C-07%2BJc0dmp26W2_H08Rsrs1V_sjEs1pkG6xuZZ75OcTa%2Bw%40mail.gmail.com <https://groups.google.com/d/msgid/geoengineering/CAJ3C-07%2BJc0dmp26W2_H08Rsrs1V_sjEs1pkG6xuZZ75OcTa%2Bw%40mail.gmail.com?utm_medium=email_source=footer>. -- You received this message because you are subscribed to the Google Groups "geoengineering" group. To unsubscribe from this group and stop receiving emails from it, send an email to geoengineering+unsubscr...@googlegroups.com <mailto:geoengineering+unsubscr...@googlegroups.com>. To view this discussion on the web visit https://groups.google.com/d/msgid/geoengineering/CH2PR04MB6936220B9B7203A2CB55EA4B8F410%40CH2PR04MB6936.namprd04.prod.outlook.com <https://groups.google.com/d/msgid/geoengineering/CH2PR04MB6936220B9B7203A2CB55EA4B8F410%40CH2PR04MB6936.namprd04.prod.outlook.com?utm_medium=email_source=footer>. -- You received this message because yo
Re: [geo] Background-Greenland collapse
"The more advanced the process, the more momentum it has, and the harder it is to stop or reverse." The same can count for social dynamics. Self-reinforcing processes with the tendency towards a lock-in are path-dependent processes. That is, why it is not easy to just change carbon intensive behavior towards low carbon emission behavior. Many social, economical, and technical processes have the production of carbon emissions as side effects which accumulate during the intensifying self-reinforcing processes (cp. Figure 4 p. 63 in https://ediss.sub.uni-hamburg.de/volltexte/2020/10431/pdf/Dissertation.pdf ). But what about the side effects of SRM that would accumulate over time while deployment in an intensity of "driving the earth into a glacial period"? It is necessary to decouple self-reinforcing processes from producing carbon emissions as a side effect. And try to potentially include the reduction of carbon emissions as side effects of new self-reinforcing processes that show the dynamic of "the more advanced the process, the more momentum it has, and the harder it is to stop or reverse". If you would plan the potential deployment of SRM (especially on a large-scale) you would in the same way have to consider the potential side effects beforehand to assure to decouple a deployment of SRM from these potential side effects. Otherwise you would risk the accumulation in acidification of the oceans, self-reinforcing the reduction in biodiversity, loss in coral reefs, accumulating in social tensions (just to name a few of the interconnected potential side effects, cp. Figure 3.1.,p.71 in the transdisciplinary network of potential side effects in: https://www.iass-potsdam.de/sites/default/files/2018-06/EuTRACE_report_digital_second_edition.pdf ). Furthermore, with SRM you address the global mean temperature. If this would work at all, this would not imply the globally even reduction of temperature, regional effects may differ a lot, potentially increasing also the climate related risks for coastal cities, which you have mentioned as your main concern to safe. Best, Jasmin Am 15.08.2020 um 13:19 schrieb Andrew Lockley: The more advanced the process, the more momentum it has, and the harder it is to stop or reverse. It's unclear whether we could arrest mass loss, without driving the earth into a glacial period (colloquially, an ice age). I don't think there has been any serious modelling work done on ice loss reversal, or even if the models are capable of doing this with any useful accuracy. On Sat, 15 Aug 2020, 12:03 Douglas MacMartin, <mailto:dgm...@cornell.edu>> wrote: What is not correct in the media report is this sentence: “This process, however, would take decades.” Well, I guess arguably that’s true, it’s just it would take a LOT of decades. Melt rate is currently of order 1-2mm/yr equivalent SLR, so to get the 6m from melting all of Greenland would take a few thousand years. Obviously it can speed up a lot, but “hey, it’s losing mass” does not remotely imply “therefore we only have a few decades before we lose our coastal cities”. So no, you can’t use this study to claim that geoengineering is required to keep our coastal cities. The problem with relying on mitigation+CDR is time-scale, but this study doesn’t prove that our response time-scale needs to be faster than what CDR can (at least hypothetically) provide. d *From:*geoengineering@googlegroups.com <mailto:geoengineering@googlegroups.com> mailto:geoengineering@googlegroups.com>> *On Behalf Of *Andrew Lockley *Sent:* Saturday, August 15, 2020 3:40 AM *To:* geoengineering mailto:geoengineering@googlegroups.com>> *Subject:* [geo] Background-Greenland collapse If this study is correct https://www.nature.com/articles/s43247-020-0001-2 And is correctly reported here https://mobile.reuters.com/article/amp/idUSKCN25A2X3 Then it appears to back up a point that I have been making for a long time: geoengineering is required, if we are to keep our coastal cities. I do not see economic or political feasibility for large scale CDR to tackle historic emissions, and thus the task must fall to SRM. Nobody has managed to rause an objection to this argument to date. I'd be grateful if those who might disagree were to raise counter arguments now. If the situation is as I understand it, prevarication has no clear benefits, and we should thus move quickly to readiness for deployment. Andrew -- You received this message because you are subscribed to the Google Groups "geoengineering" group. To unsubscribe from this group and stop receiving emails from it, send an email to geoengineering+unsubscr...@googlegroups.com <mailto:geoengineering+unsubscr...@goog
RE: [geo] Background-Greenland collapse
True that, whether one uses lots of CDR and/or SRM, it is possible that neither of those options would arrest mass loss without cooling beyond preindustrial, and that over the ensuing millennium we would eventually lose our coastal cities no matter what we do, but that we would delay that if we start solar geo sooner. But (a) we don’t know and I think your second statement is correct, that we don’t have the modeling capability for that, (b) I’m more concerned about what we do in the next 50 years, myself, so questions of whether the cities are ultimately un-savable on timescales of centuries I don’t think matters for near-term decisions (c) personally I’m a lot more worried about Antarctic than Greenland, (d) nothing you said justifies your original claim (insofar as solar geo doesn’t guarantee keeping coastal cities over long timescales either). I agree that starting solar geo today would result in less SLR by 2100 than not starting it, if emissions stayed the same, but the only thing we know in that sentence is the word “less”. Your original claim was also based on the premise of throwing out all other options. Yes, generally in any situation in life, if you refuse to consider all of the options but one, then yes, you have only one option. That’s true, but only trivially. Yes, if you rule out large-scale CDR to tackle historical emissions, then it is unequivocally true that SRM would be the only way to reduce temperatures beyond the current level. That’s not exactly a profound observation… From: Andrew Lockley Sent: Saturday, August 15, 2020 7:20 AM To: Douglas MacMartin Cc: geoengineering Subject: Re: [geo] Background-Greenland collapse The more advanced the process, the more momentum it has, and the harder it is to stop or reverse. It's unclear whether we could arrest mass loss, without driving the earth into a glacial period (colloquially, an ice age). I don't think there has been any serious modelling work done on ice loss reversal, or even if the models are capable of doing this with any useful accuracy. On Sat, 15 Aug 2020, 12:03 Douglas MacMartin, mailto:dgm...@cornell.edu>> wrote: What is not correct in the media report is this sentence: “This process, however, would take decades.” Well, I guess arguably that’s true, it’s just it would take a LOT of decades. Melt rate is currently of order 1-2mm/yr equivalent SLR, so to get the 6m from melting all of Greenland would take a few thousand years. Obviously it can speed up a lot, but “hey, it’s losing mass” does not remotely imply “therefore we only have a few decades before we lose our coastal cities”. So no, you can’t use this study to claim that geoengineering is required to keep our coastal cities. The problem with relying on mitigation+CDR is time-scale, but this study doesn’t prove that our response time-scale needs to be faster than what CDR can (at least hypothetically) provide. d From: geoengineering@googlegroups.com<mailto:geoengineering@googlegroups.com> mailto:geoengineering@googlegroups.com>> On Behalf Of Andrew Lockley Sent: Saturday, August 15, 2020 3:40 AM To: geoengineering mailto:geoengineering@googlegroups.com>> Subject: [geo] Background-Greenland collapse If this study is correct https://www.nature.com/articles/s43247-020-0001-2 And is correctly reported here https://mobile.reuters.com/article/amp/idUSKCN25A2X3 Then it appears to back up a point that I have been making for a long time: geoengineering is required, if we are to keep our coastal cities. I do not see economic or political feasibility for large scale CDR to tackle historic emissions, and thus the task must fall to SRM. Nobody has managed to rause an objection to this argument to date. I'd be grateful if those who might disagree were to raise counter arguments now. If the situation is as I understand it, prevarication has no clear benefits, and we should thus move quickly to readiness for deployment. Andrew -- You received this message because you are subscribed to the Google Groups "geoengineering" group. To unsubscribe from this group and stop receiving emails from it, send an email to geoengineering+unsubscr...@googlegroups.com<mailto:geoengineering+unsubscr...@googlegroups.com>. To view this discussion on the web visit https://groups.google.com/d/msgid/geoengineering/CAJ3C-07%2BJc0dmp26W2_H08Rsrs1V_sjEs1pkG6xuZZ75OcTa%2Bw%40mail.gmail.com<https://groups.google.com/d/msgid/geoengineering/CAJ3C-07%2BJc0dmp26W2_H08Rsrs1V_sjEs1pkG6xuZZ75OcTa%2Bw%40mail.gmail.com?utm_medium=email_source=footer>. -- You received this message because you are subscribed to the Google Groups "geoengineering" group. To unsubscribe from this group and stop receiving emails from it, send an email to geoengineering+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/geoengineering/CH2PR04MB6936FB0D9DE79204D90DE4138F410%40CH2PR04MB6936.namprd04.prod.outlook.com.
Re: [geo] Background-Greenland collapse
The more advanced the process, the more momentum it has, and the harder it is to stop or reverse. It's unclear whether we could arrest mass loss, without driving the earth into a glacial period (colloquially, an ice age). I don't think there has been any serious modelling work done on ice loss reversal, or even if the models are capable of doing this with any useful accuracy. On Sat, 15 Aug 2020, 12:03 Douglas MacMartin, wrote: > What is not correct in the media report is this sentence: “This process, > however, would take decades.” Well, I guess arguably that’s true, it’s > just it would take a LOT of decades. Melt rate is currently of order > 1-2mm/yr equivalent SLR, so to get the 6m from melting all of Greenland > would take a few thousand years. Obviously it can speed up a lot, but > “hey, it’s losing mass” does not remotely imply “therefore we only have a > few decades before we lose our coastal cities”. So no, you can’t use this > study to claim that geoengineering is required to keep our coastal cities. > The problem with relying on mitigation+CDR is time-scale, but this study > doesn’t prove that our response time-scale needs to be faster than what CDR > can (at least hypothetically) provide. > > d > > *From:* geoengineering@googlegroups.com *On > Behalf Of *Andrew Lockley > *Sent:* Saturday, August 15, 2020 3:40 AM > *To:* geoengineering > *Subject:* [geo] Background-Greenland collapse > > > > If this study is correct https://www.nature.com/articles/s43247-020-0001-2 > > And is correctly reported here > https://mobile.reuters.com/article/amp/idUSKCN25A2X3 > > Then it appears to back up a point that I have been making for a long > time: geoengineering is required, if we are to keep our coastal cities. I > do not see economic or political feasibility for large scale CDR to tackle > historic emissions, and thus the task must fall to SRM. > > > > Nobody has managed to rause an objection to this argument to date. I'd be > grateful if those who might disagree were to raise counter arguments now. > > > > If the situation is as I understand it, prevarication has no clear > benefits, and we should thus move quickly to readiness for deployment. > > > > Andrew > > > > > > -- > You received this message because you are subscribed to the Google Groups > "geoengineering" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to geoengineering+unsubscr...@googlegroups.com. > To view this discussion on the web visit > https://groups.google.com/d/msgid/geoengineering/CAJ3C-07%2BJc0dmp26W2_H08Rsrs1V_sjEs1pkG6xuZZ75OcTa%2Bw%40mail.gmail.com > <https://groups.google.com/d/msgid/geoengineering/CAJ3C-07%2BJc0dmp26W2_H08Rsrs1V_sjEs1pkG6xuZZ75OcTa%2Bw%40mail.gmail.com?utm_medium=email_source=footer> > . > -- You received this message because you are subscribed to the Google Groups "geoengineering" group. To unsubscribe from this group and stop receiving emails from it, send an email to geoengineering+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/geoengineering/CAJ3C-04pLr9SO5mJQXfUQUXxwUorOSNT1EgdO2AWLVv9Ba4h%2Bg%40mail.gmail.com.
RE: [geo] Background-Greenland collapse
What is not correct in the media report is this sentence: “This process, however, would take decades.” Well, I guess arguably that’s true, it’s just it would take a LOT of decades. Melt rate is currently of order 1-2mm/yr equivalent SLR, so to get the 6m from melting all of Greenland would take a few thousand years. Obviously it can speed up a lot, but “hey, it’s losing mass” does not remotely imply “therefore we only have a few decades before we lose our coastal cities”. So no, you can’t use this study to claim that geoengineering is required to keep our coastal cities. The problem with relying on mitigation+CDR is time-scale, but this study doesn’t prove that our response time-scale needs to be faster than what CDR can (at least hypothetically) provide. d From: geoengineering@googlegroups.com On Behalf Of Andrew Lockley Sent: Saturday, August 15, 2020 3:40 AM To: geoengineering Subject: [geo] Background-Greenland collapse If this study is correct https://www.nature.com/articles/s43247-020-0001-2 And is correctly reported here https://mobile.reuters.com/article/amp/idUSKCN25A2X3 Then it appears to back up a point that I have been making for a long time: geoengineering is required, if we are to keep our coastal cities. I do not see economic or political feasibility for large scale CDR to tackle historic emissions, and thus the task must fall to SRM. Nobody has managed to rause an objection to this argument to date. I'd be grateful if those who might disagree were to raise counter arguments now. If the situation is as I understand it, prevarication has no clear benefits, and we should thus move quickly to readiness for deployment. Andrew -- You received this message because you are subscribed to the Google Groups "geoengineering" group. To unsubscribe from this group and stop receiving emails from it, send an email to geoengineering+unsubscr...@googlegroups.com<mailto:geoengineering+unsubscr...@googlegroups.com>. To view this discussion on the web visit https://groups.google.com/d/msgid/geoengineering/CAJ3C-07%2BJc0dmp26W2_H08Rsrs1V_sjEs1pkG6xuZZ75OcTa%2Bw%40mail.gmail.com<https://groups.google.com/d/msgid/geoengineering/CAJ3C-07%2BJc0dmp26W2_H08Rsrs1V_sjEs1pkG6xuZZ75OcTa%2Bw%40mail.gmail.com?utm_medium=email_source=footer>. -- You received this message because you are subscribed to the Google Groups "geoengineering" group. To unsubscribe from this group and stop receiving emails from it, send an email to geoengineering+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/geoengineering/CH2PR04MB6936220B9B7203A2CB55EA4B8F410%40CH2PR04MB6936.namprd04.prod.outlook.com.
[geo] Background-Greenland collapse
If this study is correct https://www.nature.com/articles/s43247-020-0001-2 And is correctly reported here https://mobile.reuters.com/article/amp/idUSKCN25A2X3 Then it appears to back up a point that I have been making for a long time: geoengineering is required, if we are to keep our coastal cities. I do not see economic or political feasibility for large scale CDR to tackle historic emissions, and thus the task must fall to SRM. Nobody has managed to rause an objection to this argument to date. I'd be grateful if those who might disagree were to raise counter arguments now. If the situation is as I understand it, prevarication has no clear benefits, and we should thus move quickly to readiness for deployment. Andrew -- You received this message because you are subscribed to the Google Groups "geoengineering" group. To unsubscribe from this group and stop receiving emails from it, send an email to geoengineering+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/geoengineering/CAJ3C-07%2BJc0dmp26W2_H08Rsrs1V_sjEs1pkG6xuZZ75OcTa%2Bw%40mail.gmail.com.
