date: Mon, 12 Oct 1998 15:45:48 +0200 from: "T.Kram" subject: Re: B2 sulphur to: sres@iiasa.ac.at Dear all, I fully agree with Naki that we should be very careful with such last-minute changes, in particular if they seem to be inspired by the wish to make B2 the preferred single case. In my view there are plenty arguments in favour and against higher sulphur emissions in B2 than B1 that need to be sorted out in due course for final assessments for the final report. As Naki mentions rightfully, the model-based approach selected is not compatible with 'simply' adjusting emission coefficients ex-post. Moreover, as we need to freeze numerical data for the Open Process on very short notice (e.g. Alex already prepared graphs based on the current calculations in Beijing and we cannot continue adjusting all these numbers and graphs!). So, I suggest to leave the markers unchanged as there are no convincing arguments in support of S-emissions being "too low" in B2. In the worst case we may want to revise our position somewhat in the final report, causing slightly less global climate effect and less regional spread in temperature forcing due to the higher S emissions. Tom PS: If the group decides not to adhere to my views, an extremely tight schedule will have to be developed to ensure that new runs are made and data are made available on the Website before the end of the month. So we must decide very, very quickly. Tom ---------- From: Nebojsa NAKICENOVIC To: sres@iiasa.ac.at Cc: johnson@thames.iiasa.ac.at Subject: Re: B2 sulphur Date: maandag 12 oktober 1998 15:15 Laurie and Ken, I appreciate the importance of this discussion and full review of all model runs. However, we need to be absolutely careful not to make a mess of our work in the last minute, so to say. Modeling groups have now spent months harmonizing the scenarios and we all know that we still have a lot of work to do. However, we should not ask them to make fundamental changes in the scenarios while we have not yet agreed on the exact text of the storylines. I also agree with Laurie that we should resist further temptations to make B2 appear as the only baseline scenario. They all are reference scenarios. Yes, let us review sulfur and all other features of the scenarios. Please send specific comments to the modeling groups, but let us not propose fundamental changes until the proposed changes have been analyzed. Sulfur emissions calculations are based on technical emissions coefficients so that they cannot be changed by simply pushing a button. Some sulfur is removed from coal in synfuel production, other is scrubbed from powerplants, etc. Reintroducing these emissions into the final model solution requires changes in technology mix and costs meaning that we are likely to have a new scenario that is different in other aspects as well and not only in sulfur emissions. Cheers, Naki At 02:36 PM 10/12/98 +0200, Laurie.MICHAELIS@oecd.org wrote: >I agree with taking another look at sulphur profiles across the scenarios >and I'm comfortable with the idea that B2 might have higher sulphur but I do >not agree with Ken's rationale. > >The modelling community may or may not take B2 as their preferred case to >model, but we decided last week that we do not want to offer a "median >case". B2 has to have its own story. I do not believe that there is any >harm in giving the message that median variables do not necessarily go >together. > >Having said this, B2 has been explained as an environmentally conscious case >with a regional governance emphasis -- "regional self-reliance". The real >question is, do we seen this storyline as having more or less advanced >sulphur control technology than B1. The way I've currently slanted the >storylines, B1 has more technical change, and B2 has more behavioural >change. Hence, I would be comfortable with B2 having a higher emission >factor for sulphur from coal. > > > >From: > >Laurie Michaelis > >Tel +33 1 45 24 98 17 >Fax +33 1 45 24 78 76 > >OECD Environment Directorate >2 rue André-Pascal >75775 Paris >CEDEX 16 >France > > > > ----------