2012-02-18 20:00:31GISS has tampered with historical Reykjavik data that shows that the 1930.40's was warmer than it is today
John Cook


Anyone know anything about this?

I regularly use your resource to tackle deniers, just recently they have challenged me on the news that Icelands Met office is claiming GISS has tampered with historical Reykjavik data that shows that the 1930/40's was warmer than it is today
I have hunted for a comeback with no luck?

2012-02-18 23:59:21
Dikran Marsupial
Gavin Cawley

The article doesn't appear to me to suggest that the Iceland Met Office is making any such claim, just that they are unaware of any adjustment made by GISS.  I suspect this is bogus as the code for GISStemp is freely available and if that code doesn't reproduce GISStemp from the GCHN data then such an "adjustment" would be unequivocally demonstrated.  GISS would have to be stupid to do that (and they are not) and if there was a genuine issue, then there would be more than a vague story in the press with no details (note the article mentions a paper written by the Iceland Met Office, but doesn't give the information that would allow you to check it out, which rings alarm bells immediately).

This looks like a likely source (WUWT of course)


Looks to me like a case of poor journalism.  I rather doubt they contacted GISS, who I'm sure would have explained it to them.

2012-02-19 00:11:31
Dikran Marsupial
Gavin Cawley

see this reply from Tom Curtis


and this one by Nick Stokes who compared the current GCHN data with earlier versions and found they were identical


It seems that WUWT are making a fuss about well-documented quality control and homogenisation adjustments.

see also