[asa] Re: Costs of CO2 Mitigation

From: John Burgeson (ASA member) <hossradbourne@gmail.com>
Date: Wed Dec 31 2008 - 14:52:15 EST

Sorry -- my goof -- the link should read

www.burgy.50megs.com/2008 12 on GW.htm


On 12/31/08, John Burgeson (ASA member) <hossradbourne@gmail.com> wrote:
> Fascinating stuff.
> BTW, I just had an exchange of emails on this subject with a friend of
> many years (12) who happens to be a Republican Rep from Colorado. I
> was pleased to find out that we share similar views of the issues. In
> the exchange I sent a copy of my article written for the Rico Bugle
> this month.
> I'd appreciate any comments on the article from the ASA list --
> particularly Rich and Randy. It may be accessed at
> www.burgy.50megs.com/gw.htm
> I tried very hard to present the issues fairly, Ias I saw them.
> On 12/30/08, Rich Blinne <rich.blinne@gmail.com> wrote:
>> One of the things that get in the way of effective CO2 mitigation is
>> the past cost models of environmental cleanup. That is to remove ever
>> increasing amounts of whatever "toxin" it takes exponentially more
>> resources to remove it. This paradigm has been used by the denialists
>> to insure there is inaction. For example, Roger Pielke, Jr. oscillates
>> between the "models are wrong" and "it's just too expensive". In both
>> cases, we do nothing. What undergirds this approach is there is a real
>> risk with an exponentially increasing cost model that you could end up
>> spending too much. A new approach to the economics can be found in
>> today's PNAS.
>> http://www.pnas.org/content/105/52/20621.abstract
>>> One approach in climate-change policy is to set normative long-term
>>> targets first and then infer the implied emissions pathways. An
>>> important example of a normative target is to limit the global-mean
>>> temperature change to a certain maximum. In general, reported cost
>>> estimates for limiting global warming often rise rapidly, even
>>> exponentially, as the scale of emission reductions from a reference
>>> level increases. This rapid rise may suggest that more ambitious
>>> policies may be prohibitively expensive. Here, we propose a
>>> probabilistic perspective, focused on the relationship between
>>> mitigation costs and the likelihood of achieving a climate target.
>>> We investigate the qualitative, functional relationship between the
>>> likelihood of achieving a normative target and the costs of climate-
>>> change mitigation. In contrast to the example of exponentially
>>> rising costs for lowering concentration levels, we show that the
>>> mitigation costs rise proportionally to the likelihood of meeting a
>>> temperature target, across a range of concentration levels. In
>>> economic terms investing in climate mitigation to increase the
>>> probability of achieving climate targets yields "constant returns to
>>> scale," because of a counterbalancing rapid rise in the
>>> probabilities of meeting a temperature target as concentration is
>>> lowered.
>> The constant returns to scale is key. This means that by linearly
>> increasing the percentage of GDP we get a linearly increased
>> probability of achieving our temperature goals, e.g. less than three
>> degrees C rise because that would create a "different planet". The
>> methodology that is used by Schaeffer et al is to focus on the error
>> bars of the climate sensitivity. They create a concept known as the
>> "allowed climate sensitivity". This is reverse-engineered from the
>> desired temperature target and the consequent forcing. Since the
>> climate sensitivity is not known precisely there is a probability that
>> the CO2 targets actually achieve the temperature targets. As was
>> presented by Jim Hansen at the 2008 AGU most of this uncertainty is
>> due to the uncertainty of the aerosol climate sensitivity and not the
>> CO2 sensitivity proper which is well-understood and well-bounded.
>> (This is the reason why there is a >95% consensus on the existence of
>> AGW.) After all the number crunching is done what is found out is that
>> a linear increase in spending produces a linear increase in the
>> probability that we will hit our temperature targets. You can see the
>> linearity from Figure 5 of the paper. I put a copy up here:
>> http://docs.google.com/Presentation?docid=dgzxjjjz_51fsrwcvf8
>> Since the 3 degrees C target is the "different planet" line and we
>> want near certainty that this isn't crossed the minimum spending needs
>> to be 1% of GDP. (This is also quite a bit less than the 3% GDP target
>> proposed by IPCC 2007.) If we spend this amount we may get "lucky"
>> and have a much better result. The is eminently doable and does not
>> warrant the Pielke throw up the hands in despair approach.
>> Rich Blinne
>> Member ASA
> --
> Burgy
> www.burgy.50megs.com

To unsubscribe, send a message to majordomo@calvin.edu with
"unsubscribe asa" (no quotes) as the body of the message.
Received on Wed Dec 31 14:52:37 2008

This archive was generated by hypermail 2.1.8 : Wed Dec 31 2008 - 14:52:37 EST