NZ Warming – Official



By Alan Tristram
November 27th 2009



New Zealand’s official weather data group – NIWA – has strongly rebutted claims by the Climate Science Coalition that the country’s climate isn’t warming up.

NIWA – short for National Institute of Water and Atmospheric Research – says:

“Warming over New Zealand through the past century is unequivocal.”

The statement answers a claim made earlier this week by the New Zealand Climate Change Coalition, which says “New Zealand’s temperature has been remarkably stable for a century and a-half.”

The coalition accepts NIWA’s raw data but claims the figures have been ‘adjusted’ to prove there’s been warming.

It says: The shocking truth is that the oldest readings have been cranked way down and later readings artificially lifted to give a false impression of warming.”

But today NIWA says its analysis of measured temperatures uses internationally accepted techniques, including making adjustments for changes such as movement of measurement sites.

Weather Station Moved

It says: “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.”

NIWA says: “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 says its climate scientists have previously explained to members of the Coalition why such corrections must be made.

And 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.

He says NIWA scientists are committed to providing robust information to help all New Zealanders make good decisions.