cc: Daithi Stone , Tim Delsole , claudia tebaldi , "Stott, Peter" , Myles Allen , Gabi Hegerl , "Zwiers,Francis [Ontario]" , Tim Barnett , Hans von Storch , Phil Jones , David Karoly , Toru Nozawa , Ben Santer , Richard Smith , Nathan Gillett , Michael Wehner , Doug Nychka , Xuebin Zhang , "Jones, Gareth S (Climate Scientist)" , Stephen Leroy , seung-ki.min@ec.gc.ca date: Fri, 04 Sep 2009 12:35:02 -0400 from: Tom Knutson subject: Re: Second iteration to: Knutti Reto

All, FYI, I sent the following paragraph to Claudia yesterday, to flesh out my part for Subtask 2.5: Tropical cyclones and climate change: issues in detection and attribution of changes (Knutson) A key question for detection of a possible anthropogenic influence on tropical cyclones is whether the strong correlation between local Atlantic sea surface temperature and Atlantic hurricane power dissipation, as shown by observed records since 1950, also holds for a greenhouse gas-induced warming. If so, past hurricane changes might be attributable to anthropogenic forcing via an indirect attribution argument, since tropical Atlantic sea surface warming has been attributed to anthropogenic forcing. Another implication would be a very large implied increase in Atlantic hurricane activity projected for the 21st century. Thus far, dynamical models do not support such an indirect attribution or dramatic projected increase, and thus there is not yet clear evidence of an anthropogenic influence on Atlantic hurricanes. Owing to the importance of this issue, continued work will involve further analysis of hurricane observed data sets for possible homogeneity problems, and continued development and refinement of the dynamical models used to simulate climate change influences on hurricane activity. Regards, --Tom Knutson Knutti Reto wrote: > Attached some more suggestions for year 1-3 deliverables based on > Daithi's version. It's hard to say when these things will happen as none > of this is funded by IDAG, but it may not be that important in which > year we list it. > > Reto > > >> -----Original Message----- >> From: Daithi Stone [mailto:stoned@csag.uct.ac.za] >> Sent: Freitag, 4. September 2009 18:06 >> To: Tim Delsole >> Cc: claudia tebaldi; Stott, Peter; Myles Allen; Knutti Reto; Gabi >> Hegerl; Zwiers,Francis [Ontario]; Tim Barnett; Hans von Storch; Phil >> Jones; David Karoly; Toru Nozawa; Ben Santer; Daithi Stone; Richard >> Smith; Nathan Gillett; Michael Wehner; Doug Nychka; Xuebin Zhang; Tom >> Knutson; Jones, Gareth S (Climate Scientist); Stephen Leroy; seung- >> ki.min@ec.gc.ca >> Subject: Re: Second iteration >> >> Attached further comments (on Tim's and Peter's version) and the >> beginning >> of a schedule... >> Cheers, >> DA >> >>> Hi Claudia. Subtask 1.8 was completely blank, so I inserted a >> paragraph >>> and signed myself up. I've also signed up for a few more things. > My >>> insertions build upon Peter's revision submitted today. -Tim >>> >>> >>> Stott, Peter wrote: >>>> Dear Claudia, >>>> >>>> I'm attaching a version with some suggested changes and I've signed >>>> myself up for some more things. >>>> I'm also attaching a figure for inclusion with the figure caption >> below. >>>> Something to think about in the background for AR5 is who might > step >>>> into the mighty shoes of Daithi for providing detection and >> attribution >>>> figures and analysis on the CMIP ensemble for AR5 - I don't imagine >>>> Daithi wants to do that again so hopefully we can find a worthy >>>> successor ! >>>> >>>> Thanks very much for all your efforts ! >>>> Peter >>>> >>>> >>>> >>>> Distributions of near-surface temperature trends during 1950-1997 > in >>>> different regions constrained by the global analysis in a climate >> forced >>>> with both anthropogenic and natural forcings (red lines) and with >>>> natural forcings only (green lines). The y axis gives the > normalized >>>> likelihood. The observed trend in each region is marked on each >> panel as >>>> a black line. The regions are South Australia (SAU), North > Australia >>>> (NAU), Central America (CAM), Western North America (WNA), Central >> North >>>> America (CAN), Eastern North America (ENA), Mediterranean Basin >> (MED), >>>> Northern Europe (NEU), South Asia (SAS), Atlantic (ATL), Pacific >> (PAC). >>>> Their geographical extents are defined in Christidis et al (2009). >>>> >>>> >>>> Dr. Peter Stott >>>> Head, Climate Monitoring and Attribution, >>>> Met Office Hadley Centre, Fitzroy Road, Exeter. EX1 3PB, UK >>>> Tel +44(0)1392 886646 Fax +44(0)1392885681 >>>> Email: peter.stott@metoffice.gov.uk >>>> http://www.metoffice.gov.uk >>>> -----Original Message----- >>>> From: claudia.tebaldi@gmail.com [mailto:claudia.tebaldi@gmail.com] >> On >>>> Behalf Of claudia tebaldi >>>> Sent: 31 August 2009 17:05 >>>> To: Myles Allen; Knutti Reto; Stott, Peter; Gabi Hegerl; >> Zwiers,Francis >>>> [Ontario]; Tim Barnett; Hans von Storch; Phil Jones; David Karoly; >> Toru >>>> Nozawa; Ben Santer; Daithi Stone; Richard Smith; Nathan Gillett; >> Michael >>>> Wehner; Doug Nychka; Xuebin Zhang; Tom Knutson; Tim Delsole; Jones, >>>> Gareth S (Climate Scientist); Stephen Leroy; seung-ki.min@ec.gc.ca >>>> Subject: Second iteration >>>> >>>> Dear all, >>>> >>>> First of all, thank you to all of you that replied to my first > draft >>>> with thoughtful comments, suggestions, edits, content. I tried and >>>> incorporated all that I could in this second version. >>>> The thing still needs your input, but hopefully this time it is a >> more >>>> targeted, specific set of things you can give me, and hopefully not >> as >>>> time consuming. >>>> My goal would be to have the proposal ready for submission at the >> end of >>>> next week, but we'll see. >>>> >>>> So, here is what I would like to get from you *by the end of this >>>> week* so that I can work on it for a few more days before that >>>> (admittedly arbitrary) deadline. >>>> Actually, one thing I would like you to do sooner, i.e. as soon as >> you >>>> get this email, is to reply telling me if you are (or want to be) a >>>> funded member, and, in that case, including a short bio. >>>> >>>> Then, for the proposal's narrative, I would like it of course if > you >>>> read the entire thing again and checked/edited/suggested again if >> you >>>> see something you don't like or would like changed. I don't have > any >>>> figures yet in there and it would be extremely helpful if I could >> get a >>>> few (with captions) to make the proposal less black and white. >>>> >>>> The most important feedback I need is related to the work plan, >> where >>>> some of you are missing still. Please go through it and sign >> yourself >>>> up. And if you see items that are still only a single sentence, >> please >>>> flesh those out. Even more importantly, I need specific > year-by-year >>>> deliverables from the various groups that are responsible for the >>>> tasks/subtasks. Maybe the heads of the groups can come up with > that >>>> kind of prediction/promise. >>>> >>>> That's about it. There are a few specific comments in the text > where >> I >>>> need info, you'll see, but those are few and sparse. >>>> >>>> So, summarizing >>>> >>>> ASAP: >>>> - Do you need money? Reply immediately with a yes or no, >> please, >>>> and send brief bio if the answer is yes (all) BY THE END OF THIS >> WEEK >>>> (meaning you can use the weekend too!): >>>> - Check narrative as a whole (all) >>>> - Contribute a figure w/caption (all) >>>> - Sign up for tasks/subtasks (all) >>>> - Come up with year-by-year deliverables (Tasks' quadres) >>>> >>>> Thank you all for your help. Again, I hope I did not >> misrepresent/forget >>>> anything substantial in trying to merge all the different streams > of >>>> feedback you kindly provided. >>>> I'm attaching the document in two formats, so that hopefully >> everybody >>>> will be able to open it ok (I'm trying to preemptively eliminate >> every >>>> excuse you can come up with for not doing this ;-) ) >>>> >>>> bye >>>> >>>> c >>>> -- >>>> Claudia Tebaldi >>>> Research Scientist, Climate Central >>>> http://www.climatecentral.org >>>> +1 (303) 775 5365 >>>> >>> >>> -- >>> Timothy DelSole >>> Associate Professor >>> Department of Atmospheric, Oceanic, and Earth Sciences >>> George Mason University >>> Fairfax, VA >>> >>> Mailing Address: >>> Center for Ocean-Land-Atmosphere Studies >>> 4041 Powder Mill Rd. >>> Suite 302 >>> Calverton, MD 20705-3106 >>> >>> email: delsole@cola.iges.org >>> Office: 301-902-1258 >>> Fax: 301-595-9793 >>> COLA: 301-595-7000 >>> >>> >>> >> > -- Tom Knutson ----------------------------------------------------------------------- Geophysical Fluid Dynamics Lab /NOAA | phone: +1-609-452-6509 201 Forrestal Road | fax: +1-609-987-5063 Princeton, New Jersey 08542 U.S.A. | e-mail: Tom.Knutson@noaa.gov Homepage: http://www.gfdl.noaa.gov/tom-knutson-homepage