date: Tue Oct 30 10:39:40 2007
from: Tim Osborn <t.osborn@uea.ac.uk>
subject: Re: Questions about CRU CL 1.0
to: Ian Harris <I.Harris@uea.ac.uk>

   Harry -- I'm catching up on old emails including the one below from a month ago... the
   answer is "no" I don't know.  Helpful aren't I?!  Tim
   At 09:17 26/09/2007, you wrote:

     Hi Phil, Tim,
     Do either of you know the answers to these questions?
     Cheers
     Harry
     On 26 Sep 2007, at 8:48, Sheppard Sylv Miss ((SCI)) wrote:

     -----Original Message-----
     From: Jongschaap, Raymond [[1]mailto:raymond.jongschaap@wur.nl]
     Sent: Wednesday, September 26, 2007 8:16 AM
     To: Sheppard Sylv Miss (SCI)
     Cc: Jongschaap, Raymond; Conijn, Sjaak
     Subject: Questions about CRU CL 1.0
     Dear Dr Mitchel, or CRU colleague,
     I would like to know if you could help me out with some questions
     concerning the CRU CL 1.0 data-set, that is available on your website.
     In the above database radiation (rad, W m-2) is provided, although
     in the paper of New et al. (1999), this variable is not mentioned.
     My questions are:
     1) Where can I learn how this variable was derived, and
     2) As Rad is given as W m-2 (or J m-2 s-1); is this an average
     value for a day in a given month? Does this apply for 24 hours, or
     for the daylength period only? As you may understand, I would like
     to obtain the daily or monthly value of rad, and don't know which
     mulitplier I should use.
     My last question is about vapour pressure (vap, hPa) and wind speed
     (wnd, m s-1)
     3) Are these mean values for a day (24 h) in a given month or do
     they apply for the daylength period of that day only?
     I hope you can help me out ASAP with some (partial) answers,
     Best personal regards,
     Dr. ir. R.E.E. Jongschaap
     Sustainable farming systems, Bioenergy, Simulation modeling and
     Remote Sensing
     Wageningen University and Research centre
     Plant Sciences Group
     Plant Research International
     Dept. Agrosystems Innovations
     T +31 (0)317 475953 / [new: 480570]
     F +31 (0)317 423110
     E raymond.jongschaap@wur.nl
     W [2]www.pri.wur.nl
     Postal address:
     P.O. Box 16
     NL-6700AA Wageningen
     the Netherlands
     Visiting address:
     Bornsesteeg 65
     Building 122, room 0.24
     NL-6708PD Wageningen
     the Netherlands
     Jatropha curcas evaluation, breeding and propagation programme
     W [3]www.jatropha.wur.nl

     Ian "Harry" Harris
     Climatic Research Unit
     School of Environmental Sciences
     University of East Anglia
     Norwich NR4 7TJ
     United Kingdom

