date: Sun, 25 Apr 1999 22:52:03 +0100 (BST)
from: Richard Jones <rgjonesatXYZxyzo.gov.uk>
subject: Comments on 10.1
to: tar10atXYZxyz.uct.ac.za (TAR 10 mailbox)
Here are my first thoughts on the draft of 10.1 - constructive
comments I hope which I am prepared to have shot down!
10.1 para 1: Another reason for the high level of uncertainty surely is
simply that the resolution of models to date have precluded the
direct extraction of useful information at fine scales simply because
they have no skill at their gridscale or below. Also, the last sentence
implies regional climate is determined by processes that span many
scales and are non-linear hence is poorly modelled and so global climate,
which we can model reasonably well, is not determined by such processes
- though in reality it is. I think I know what you are trying to say but
the statement is too strong (and misses important points about the
direct effects of lack of resolution as I have implied above).
10.1 para 4 sentence 5. I would replace beginning by starting.
10.1.1 para 1 sentence 4: I would rather start with "Biases in the
simulation of present day climate compared ..."
10.1.2 para 1: I think the lower partition of the scale ranges should be
10^4 km^2 as this corresponds to 2x2 gridboxes of a 50km model and hence
about the limit of skill of most current RCMs. I know this is somewhat
arbitrary, but it does give a sensible reference point - if 10^3 km^2
is used then we should give a reason, a typical length-scale of some
important local forcing or something similar.
10.1.2 para 3 sentence 3: I think "These interactions ... can be highly
non-linear" is more accurate. I think if we push this non-linearity idea
too hard we are in danger of implying the problem is intractible without
very high resolution GCMs with greatly improved physics.
Richard Jones (Rm H304) - Tel. (44) 01344 856418 Fax. (44) 01344 854898
Hadley Centre for Climate Prediction and Research, UK Met. Office,
London Road, Bracknell, RG12 2SZ, UK.
Email - local : hadrj@hc0500 : - Internet : rgjonesatXYZxyzo.gov.uk