Simple GISS diagram illustrating warming effect of conventional “adjustments” of “step” in T data due to site moves outward from urban centre.January 2nd, 2011 by Warwick Hughes
I have been reading the 169 page NIWA pdf – “Report on the Review of NIWA’s “Seven-Station” Temperature Series December 2010″ – downloaded here
I have not yet found the BoM review – only the one page letter from the BoM – see pdf page 13 in the above.
I draw readers attention to the excellent little GISS diagrams which perfectly illustrate the warming effect of adjusting out the multitude of step changes which are common throughout all temperature data as thousands of recording sites have been moved outwards in their respective urban areas.
GISS illustrating typical urban T data with a step due to outward site move – before adjustment.
GISS illustrating typical urban T data with a step due to outward site move – after adjustment – now with UHI warmed trend built in.
Reading their 169 page pdf report above – it is crystal clear that NIWA do exactly this – repeatedly adjusting out step changes – all through their seven station series – in this way NIWA cement UHI warming in their NZ 7 station century long adjusted trend.
PS: I had a little post on this in 2006