NIWA Media Release 26 November 2009
Warming over New Zealand through the past century is unequivocal.
NIWA’s analysis of measured temperatures uses internationally accepted techniques, including making adjustments for
changes such as movement of measurement sites. For example, in Wellington, early temperature measurements were made near
sea level, but in 1928 the measurement site was moved from Thorndon (3 metres above sea level) to Kelburn (125 m above
sea level). The Kelburn site is on average 0.8°C cooler than Thorndon, because of the extra height above sea level.
Such site differences are significant and must be accounted for when analysing long-term changes in temperature. The
Climate Science Coalition has not done this.
NIWA climate scientists have previously explained to members of the Coalition why such corrections must be made. NIWA’s
Chief Climate Scientist, Dr David Wratt, says he’s very disappointed that the Coalition continue to ignore such advice
and therefore to present misleading analyses.
NIWA scientists are committed to providing robust information to help all New Zealanders make good decisions.