From	Phil Jones	Date	Thu Sep 9 13:52:25 2004
To	Tom Wigley
CC	Ben Santer
Subject	Re: question
Tom, Program and the input LKS file. Program is adapted from one I had. Ended up a little convoluted. Should work with any of the 4 CRU temp data files (CRUTEM2(v), HadCRUT2(v)). For the Russian, grid point, changing 4 59 to 4 57 will give a box with data in from 1929. 3rd file is my unix run file - for files to channels. Cheers Phil At 12:20 09/09/2004, D M R Taplin wrote: Phil, Thanx. Looks very interesting. I will look more when I get back to Boulder. It would help if you sent the program (just to Boulder). Also what are the numbers listed at the end of the LKS file? Will you be reading email while away? Tom. ==================== Professor David Taplin DSc Coliemore House Down Thomas Plymouth PL90BQ UK From: Phil Jones To: Tom Wigley CC: Professor David Taplin , Ben Santer Subject: Re: question Date: Wed, 08 Sep 2004 13:44:44 +0100 Tom, Here are some files to look at and think about. John Lanzante has sent me the locations of the 87 stations in the LKS dataset. I associated these with CRU 5 deg grid boxes and calculated NH (based on 54 sites), SH (32) and Global (as one domain), so to get the globe the CRU way you need to average the NH and SH series (all to 3 deg places). The second line in all the results files is the count of stations. I can do this as % area if you want. The CRU data I used is the file hadcrut2v, so this includes SST anoms over the ocean. I can repeat this with the land only file. Used the variance corrected version. There are 4 files 1. The LKS stations. This is what John sent with the lat/long identifiers for the grid boxes on the front. 2-4 NH, SH and Globe as one domain results. The first file has a fix in it. This is to pick up the 5 deg square (85-90S, 5W-0) that has the South Pole data. This square is where I've always put this data. For the NH there were 54 sites and for the SH 32. Site 9 (WMO ID 21504) is always missing, even with hadcrut2v. The site is located on an island in the Laptev Sea. There isn't a surface site anywhere near it. I could move the location and pick up the nearest CRU box, but it will be over 5 deg of lat and 10 deg of long away. It's somewhat unusual for sonde sites not to have a surface site near them. I guess it just doesn't report its surface data. I'm here until Sept 15 then away for much of the time until end of October. I could send you the program, which should run with crutem2v or the non-variance adjusted versions, which you could pick up from the CRU web site. Cheers Phil At 15:57 04/09/2004, Tom Wigley wrote: Phil, On Sept. 13-17 I will be at a meeting at the Met Office to do with a report we are writing on trends in vert temp profiles as part of the US Climate Change Science Program (CCSP). It involves all the usual suspects. Seven chapters, the last of which is equivalent to a summary for policy-makers -- for which I am the lead author. Various people are updating data sets and doing calculations of trends, etc. Some of the surface numbers I found to be a bit disturbing -- so I am asking for your opinion. These are trends per decade for Jan. 1979 thru Dec. 2003 ...... SOURCE GLOBE 30S-30N HadCRUT2v 0.169 0.127 NCDC 0.151 0.146 ERA40 0.113 0.032 LKS 0.074 0.056 (1) CRU and NCDC are consistent within the noise, but I have one question -- how do both calculate GLOBE? (2) ERA40 is marginally OK (relative to CRU) in GLOBE, but the tropics is alarmingly different. (The diff here accounts for the GLOBE difference.) Why is this? Which is better? Is this discussed in your paper with Adrian? (3) LKS is the surface data from the corrected LKS radiosonde data set. The difference here must be partly due to coverage issues. But I recall that years ago we saw a difference between surface sonde and CRU data. Have you done a like with like comparison (i.e., selecting the LKS sonde sites and extracting the corresp CRU (and NCDC, and ERA40 -- and (if possible) NCEP) data? This seems to be a pretty basic sanity check on the sonde data -- so, if you have not done this already, could you do it for me please? I think there is a nice little GRL paper here. For the CCSP we are also giving trends, etc. over 1958-2003. So the real need is for a full time series comparison over this period -- i.e., not just trends. In other words, what I would like you to produce is the monthly time series for the various data sets for the LKS coverage. If you don't know the LKS site locations, I can get these for you. Re going back to 1958, the sonde trop data have a well known (but not well explained) problem over roughly 1958 to 1964/5. I am curious as to whether this shows up in the LKS surface record. I am also curious about the apparent 1976 jump -- some people have made a lot of noise about this, but I don't see it as a major item in the global surface data. So the Q here is, is is apparent in the restricted coverage of the sonde data? I hope you can help. I am leaving here on Sept 7 to spend a few days with a friend of mine in Plymouth -- you could contact me thru him (I am copying this to him so you can see his email). Thanx, Tom. 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 ---------------------------------------------------------------------------- << lksdata.out >> << lksnh7003v.dat >> << lkssh7003v.dat >> << lksgl7003v.dat >> 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 ----------------------------------------------------------------------------