Thanks for highlighting the "budget approach", Navroz. May I add that the corresponding work of Meinshausen et al. has been neatly digested in a 40-page special report by the German Advisory Council on Global Change (i.e. WBGU). It is a very accessible presentation of this rather complex matter and contains a number of graphs and figures that have proved really useful for public presentations and teaching.
http://www.wbgu.de/en/special-reports/sr-2009-budget-approach/ Best, Steffen ************************************** DEUTSCHES INSTITUT FÜR ENTWICKLUNGSPOLITIK (DIE) German Development Institute Dr. Steffen Bauer Tulpenfeld 6 D - 53113 Bonn TEL : 0228-94927-153 FAX : 0228-94927-130 mailto : steffen.ba...@die-gdi.de web: http://www.die-gdi.de ************************************** Re: [gep-ed] IPCC question Navroz Dubash An: rmitchel 06.08.2012 08:21 Gesendet von: gep-ed@googlegroups.com Kopie: Radoslav.Dimitrov, stacy.vandeveer, Gep-Ed Bitte Antwort an ndubash It is worth pointing out to students that there has been a great deal of discussion post AR4 on this issue. In particular, there has been interesting work and very influential work by Meinhausen et. al. 2009 in Nature articulating the challenge in terms of stocks of carbon rather than flows - a carbon "budget". This formulation computes the number of tons of carbon that we can collectively emit from now until 2050 in order to stay below 450ppm. The political challenge under this construct is to figure out a budget allocation for each country, and then a subsequent trajectory of emissions for each country that correspond to that budget. But once the budget is set, there are many possible trajectories of flows that countries could aim for; the important outcome is the area under the emissions curve, or the contribution to stock. What I find interesting about this formulation, which will almost certainly get a lot of prominence in AR5, is that it speaks to the different political implications of alternative scientific formulations. The budget formulation is more correct scientifically (what matters for CC is stocks, not flows), and changes the framing of the allocation question from formulations such as "peaking year" and annual emissions to allocations of an overall budget. Also, lends itself to factoring in historical emissions and introduces an additional complexity of deciding a starting year (1860 = pre industrial; 1970, 1990, 2000, the present etc.). I do not know if an explicit budget formulation will be the basis for negotiation going forward, but it has already certainly been introduced by the BASIC countries at Durban. From a pedagogical point of view, making explicit the political implications of stock vs flow articulations, and the strategic dimensions of alternative scientific formulations may be useful. I realize this goes a bit beyond the question being posed, but I think all this is an important update to that question. Navroz. On Mon, Aug 6, 2012 at 12:15 AM, Ronald Mitchell <rmitc...@uoregon.edu> wrote: A propos of this discussion, here is a slide from my Intro-IR climate lecture that shows not only the levels Rado is mentioning but has the added bonus of being really depressing, since it shows that this is a level of 2 tons per person and that China is already averaging double that (though those Americans on the list are proud to say we are doing 5x that). Ron From: gep-ed@googlegroups.com [mailto:gep-ed@googlegroups.com] On Behalf Of Radoslav Dimitrov Sent: Sunday, August 05, 2012 10:49 AM To: stacy.vandev...@unh.edu Cc: Gep-Ed (gep-ed@googlegroups.com) Subject: Re: [gep-ed] IPCC question Depends on the temperature target: To keep global temperature rise below 2 degrees C, carbon-equivalent atmospheric concentrations must be kept below 450 ppm - which can be achieved by reducing emissions by 25-40% by 2020. The latter range is in the 2007 IPCC report and was the policy target advocated officially by the European Unionat the Bali conference. This was a subject of intense negotiations. No one else in the industrialized camp supported the EU on this. As a result, the Bali text only contains a footnote that indirectly refers to the IPCC-endorsed target, without actually containing the 25-40 numbers. Radoslav S. Dimitrov, Ph.D. Associate Professor Department of Political Science University of Western Ontario Social Science Centre London, Ontario Canada N6A 5C2 Tel. +1(519) 661-2111 ext. 85023 Fax +1(519) 661-3904 Email: rdimi...@uwo.ca On 2012-08-05, at 1:27 PM, VanDeveer, Stacy wrote: Hi all, I got a question from a summer school student, and I am trying to find the ‘consensus’ answer in IPCC documents and I seem to be finding different numbers. So here is the question: The IPCC estimates that global emissions must fall by how much, to stabilize the climate systems during this century. Are the best estimates from the 2007 report (which gives quite large ranges for each of four warming scenarios)?? Stacy D. VanDeveer Associate Professor University of New Hampshire Dept. of Political Science Horton SSC Durham, NH 03824 USA stacy.vandev...@unh.edu tel: fax: mobile: Skype ID: (+1) 603-862-0167 (+1) 603-862-0178 (+1) 781-321-5880 stacy.d.vandeveer Want to always have my latest info? Want a signature like this? <image001.jpg> -- Dr. Navroz K. Dubash Senior Fellow Centre for Policy Research Dharma Marg Chanakyapuri New Delhi 110 021 India Tel: +91-11-2611-5273/74/75/76 Fax: +91-11-2687-2746 Email: ndub...@gmail.com
