Sat, 9 May 2009 09:18:35 +010 ???
"Lockwood, M (Mike)" <???@stfc.ac.uk>
RE: Quick question
"Phil Jones" <???@uea.ac.uk>
Yes, I thought it would have been done - but just wanted to check. I came to the same conclusion in that I estimated that we'd need 10 more years of decline from now on before it was really significant. I might yet use what I have done as part of a paper to counter the nonsense that Nicola Scafetta keeps spouting about dual timescale responses to solar changes - but then I'm not looking to waste my time either! What I could do, if you were happy with this, is use it alongside the same analysis applied to HadCRUT4 when it is ready. Would be delighted to share authorship if you think that's a worthwhile idea.
Thanks for the papers - they'll be very useful. Am in Stockholm and look forward to reading them on 'plane back (as far as my ageing laptop battery allows)
No, I didn't know about the drifter buoys effect. Dare I ask, but are their effects relevant to the recent difference between your reconstruction and GISS's? As a general point, it does amaze me how bad we (=mankind) are about keeping vital data sequences on our planet homogeneous. The worst example is space based radiometry. I hate to sound like Nigel Fox, but he's absolutely right and the whole cosmic ray cloud thing would never have got off the ground with properly intercalibrated instruments. Are the Hadley folk using the ATSRs to calibrate the drifter effect? They ought to:
that has been one dataset that is decently homogeneous. (I do worry what might happen to it when the Italians get hold of it, though!)
Phil Jones [???@uea.ac.uk] Sent:
Thu 07/05/2009 15:17
Lockwood, M (Mike)
RE: Quick reply and another quick question ....
Attached a paper and a box in a longer article that do similar things to what you've done.
So I think it's been done, unless you think otherwise.
The box is on page S20-21 of the bigger pdf. This is part of a much bigger article
on the State of the Climate System 2008 which will appear later in the year.
Bottom line - the no upward trend has to continue for a total of 15 years before
we get worried. We're really counting this from about 2004/5 and
not 1998. 1998 was warm due to the El Nino.
There are a lot of obtuse people out there, who will ignore these two refs - the first is out,
the second by about late summer. There is another issue that you should be aware of.
It was alluded to in the third pdf.
There is an issue with all the buoy data (drifters) entering SST analyses since about 2000.
First there seem to be offsets of 0.1 to 0.2 deg C between these drifters and
conventional ships (drifters cooler). Drifters now dominating , providing about 80%
of the obs. Drifters sample the diurnal cycle better than ships, which may be one of the factors
that could explain the difference. As the 61-90 period is a ship-based normal, this
means a cool bias (of about 0.1 deg C). Second, these drifters get to regions where
few ships used to go (the Southern Oceans for example), so our interpolated 61-90
normals get really tested! There will be a new version of HadCRUT3 (which we will call
HadCRUT4!) at some point later this year. The Hadley Centre need to finish their new SST
dataset first (HadSST3). This will also sort out the 1945-60 issue in the Nature paper and
add in more SST data for WW1 and WW2. Expecting to see the HadSST3 paper any
month now. Land will barely change. Likelihood is that the recent few years will increase by up to 0.1
deg C. Effect gets worse as drifter/ship ratio increases.
Scanned by iCritical.
If you found this helpful please Like it, Share it or +1 it (or do all three!). BTW: Easily follow numerous AGW blogs on our Blogs Page
List of files