cc: "Klein Tank, Albert" <Albert.Klein.Tank@knmi.nl>, David Easterling <David.Easterling@noaa.gov>, Jim Renwick <j.renwick@niwa.co.nz>
date: Wed Apr 20 17:00:07 2005
from: Phil Jones <p.jones@uea.ac.uk>
subject: Re: 3.3 and 3.8
to: Kevin Trenberth <trenbert@ucar.edu>

    Kevin,
       Although CA had record rains they occurred in bursts from October to March, as opposed
    to in a couple of months (Jan/Feb) as in the classic El Ninos.  Need to make clear
   somewhere
    these extremes were very atypical. There was one year someone said it was like,
    but I can't recall which. It just goes to show that when we think we know something,
   Nature
    changes the deck.
       Any SST-based index is likely to be a permanent El Nino state with a little more
   warming,
    unless the base period is changed. Wouldn't one based on SOI be less susceptible.
       The paper may be relevant.  Seems to conclude lots of things happening in the Arctic,
    but can't be explained by the AO (NAM) or the NAO.
    Cheers
    Phil
   At 16:38 20/04/2005, Kevin Trenberth wrote:

     Phil raises a good point I forgot: the need to briefly annotate the comments.
     On ENSO: The recommendations to NOAA was that the single best index: if you want to have
     just 1, is Nino 3.4.  I agree with that.  But it was also recommended that it should not
     be applied with a threshold such that once it crosses it is EN and if it doesn't cross
     it is not!   In fact at least 2 indices are essential as we have documented, and we
     proposed the TNI: the trans Nino index  which is the normalized difference between Nino
     4 and Nino 1+2.    Historically all nino regions have been strongly correlated, but with
     lags: before 1976 Nino 1+2 led N 3 and N 4 by several months.  After 1976 Nino 3.4 led
     1+2 by several months: a reversal in evolution, and some responses on the coast have
     been wimpy: we have seen that especially in last 2 events, so not much in 1+2 region at
     all. (One can argue that it relates to warming of oceans and esp Nino 4 region)
     This past year has been remarkable in US: the wimpy EN has nonetheless had major impacts
     with record rains in southwest (Arizona, CA, N Mexico) and drought in northwest
     (Washington, Idaho).  On satellite mean OLR you can see visually the direct link from
     anomalous convection near or west of dateline to California, so I don't think there is
     much doubt of a causal link.  But it is not really much of a classical EN even though
     conditions are quite anomalous.  Need to deal with the different flavors of EN, as I
     have been saying for years.
     Nino 3.4 is related to the basin scale mean and relates best to anomalous tropical
     precip.  TNI discriminates between Nino 4 and Nino 1+2 and allows evolution to be
     described: it is related to Nino 3.4 at leads or lags on average.  Nino 4 has been very
     high and Nino 1+2 not, so TNI has played a major role over past year.
     The following are the relevant pubs.
     Trenberth, K. E., and D. P. Stepaniak, 2001: Indices of El Nio evolution. J. Climate,
     14, 16971701.
     Trenberth, K. E., D. P. Stepaniak and J. M. Caron, 2002: Interannual variations in the
     atmospheric heat budget. J. Geophys. Res., 107(D8), 4066, 10.1029/2000D000297
     Trenberth, K. E., J. M. Caron, D. P. Stepaniak and S. Worley, 2002: Evolution of El Nio
     Southern Oscillation and global atmospheric surface  temperatures.  J. Geophys. Res.,
     107(D8), 4065,10.1029/2000D000298.
     Kevin
     Phil Jones wrote:

      Dear All,
          I was going to reply an hour ago to your emails, but got so fed up with
     interruptions
      here that I went somewhere quiet to try and read Kevin's new 3.4.1. Latter is good and
      I'll transfer my comments tonight and send to Kevin tomorrow.
          What I was going to suggest was tracked changes but just of your sections and we
      merge them in Beijing - or I can do this if you send me them by May 5. Probably best if
      we just bring all to China. Important, though, in all you do, is to note in the reviews
     that
      you've responded to each comment in some way. So keep track there as well - remembering
      the two sets of comments from the LAs and the formal WG1 reviews. These responses can
      be brief - even just say done.  Also we are supposed to get a few more reviews from
     WG1.
          When you're doing this Albert, it is best for almost all aspects of extremes to be
      in your section, so note potential overlaps. I looked through the BAMS review whilst in
     a
      hotel room one night a week or two ago and it does contain a lot of useful info and
     some
      other diagrams in addition to the hurricane one. We should discuss the ACE work in
      Beijing at some point. It would be good to have something on that.
          One thing - linking it to ENSO stirred a chord ! We need to decide on a definition
     of ENSO
      (Nino3.4, SOI or whatever) and what are El Nino and La Nina years. I'm not advocating
      anything - except that we don't use the stupid new NOAA definition ! It seems that only
      NOAA think we've had or are in an El Nino. If any chapter amongst all of IPCC should
      have a definitive index and or list of moderate/strong years it should be us. It should
      be a good one though - I'm sure you have one in something you've done Kevin, or there
      is one you prefer that we can update. Darwin SOI is fine with me, maybe we can add
      a list of the key years to the Table in 3.6.
      Cheers
      Phil
     At 15:34 20/04/2005, Kevin Trenberth wrote:

     Hi guys,
     I suggested earlier, that it is desirable if you can use track changes and come to
     Beijing with proposed revised text.  I realize it will be a logistical nightmare trying
     to bring all the stuff together, but it is important to be able to compare with one
     another on the proposed changes and get agreement: sanity checks from at least one other
     person before changing text for the FOD.  ie.we need to keep making progress, not two
     steps forward and one backwards, as part of it degrades.  Great figures (can be new)
     will be much appreciated.
     As David knows, I have been working with David Levinson on a new figure on global
     aspects of hurricanes.  I think that whole section is very imnportant yet the ZOD falls
     way short.  But the 2004 BAMS climate review, coming out in June and which I sent
     around, has all the basic material to allow a much better and more balance view of this
     issue, and it requires someone spending the time to pull out the relevant material.  I
     wonder if you, Albert can have a crack at that?  I went through and marked up some
     areas.  David also provided me with a global view of the ACE index.  He is not
     comfortable enough with it to have it published, but it is interesting and can be
     discussed.  The key aspects here are that ENSO perturbs the distribution of hurricanes
     in every basin.  With EN there is a decrease in Nth Atlantic but marked increase in E N.
     Pacific and also W N Pacific.  So the most active year globally on record is 1997 by
     far, and second is 1992, also an El Nino year.  We have a lot of the ingredients on this
     in the Nth Atlantic sectiuon, but the others are weak.
     Once material is revised, we will integrate it in Beijing into a master copy.  Bring
     your memory sticks.
     Kevin
     Klein Tank, Albert wrote:

Phil,

Yes, I have planned time to work on the comments before the meeting. Is
it OK to use track changes and edit Kevin's FOD? And can I make changes
everywhere in the chapter (which will give us multiple versions of Ch3 in
Beijing) or only in certain sections?

I also intended to make brief notes to the comments in the table that
Kevin send and the table that was send to us by the TSU. Here again my
question is: do we just go ahead and integrate everything in Beijing?

Albert.





-----Original Message-----
From: David Easterling
[[1]mailto:David.Easterling@noaa.gov]
Sent: woensdag 20 april 2005 14:58
To: Phil Jones
Cc: Klein Tank, Albert; Kevin Trenberth
Subject: Re: 3.3 and 3.8


Phil,

I will have some time to do revisions before the meeting.  I was
wondering just how far to go prior to the meeting.

Dave

Phil Jones wrote:



 Albert, Dave,


       Will either of you have much
time to do any revisions of
sections 3.3 and 3.8
 before LA2? Have any of the other LAs contacted you about
revisions?
I've been
 discussing 3.2 with David, and Kevin has rewritten 3.4.1, so am
wondering how
 your timetables are between now and LA2?  Deciding in 3.3 on
which
precip series
 to show was the reason for sending the new data from GPCC.

       All alternate/revised diagrams will
be vitally important in
Beijing. David has
 sent me 3 for 3.2.

 Cheers
 Phil




Prof. Phil Jones
Climatic Research Unit
Telephone +44 (0) 1603 592090
School of Environmental Sciences    Fax +44 (0) 1603
507784
University of East Anglia
Norwich
Email
[2]p.jones@uea.ac.uk
NR4 7TJ
UK
----------------------------------------------------------------------------






--
****************
Kevin E.
Trenberth
        e-mail:
[3]trenbert@ucar.edu
Climate Analysis Section,
NCAR
        [4]www.cgd.ucar.edu/cas/
P. O. Box
3000,
        (303) 497 1318
Boulder, CO
80307
        (303) 497 1333 (fax)

Street address: 1850 Table Mesa Drive, Boulder, CO  80303

     Prof. Phil Jones
     Climatic Research Unit        Telephone +44 (0) 1603 592090
     School of Environmental Sciences    Fax +44 (0) 1603 507784
     University of East Anglia
     Norwich                          Email    [5]p.jones@uea.ac.uk
     NR4 7TJ
     UK
     ----------------------------------------------------------------------------


--
****************
Kevin E. Trenberth                              e-mail: [6]trenbert@ucar.edu
Climate Analysis Section, NCAR                  [7]www.cgd.ucar.edu/cas/
P. O. Box 3000,                                 (303) 497 1318
Boulder, CO 80307                               (303) 497 1333 (fax)

Street address: 1850 Table Mesa Drive, Boulder, CO  80303

   Prof. Phil Jones
   Climatic Research Unit        Telephone +44 (0) 1603 592090
   School of Environmental Sciences    Fax +44 (0) 1603 507784
   University of East Anglia
   Norwich                          Email    p.jones@uea.ac.uk
   NR4 7TJ
   UK
   ----------------------------------------------------------------------------

