The New Zealand
Climate Science Coalition
3 January 2007
NIWA data confirms that New Zealand is not warming
The announcement by NIWA that last month was one of the coldest Decembers in the last 60 years is evidence that there is
no “global warming” in New Zealand, according to the New Zealand Climate Science Coalition.
“This bears out what the coalition said in July 2006 in its open letter to members of the New Zealand Parliament, when
we pointed out that NIWA’s own data showed little evidence of warming, and no evidence that humans are affecting the
temperature,” says a statement from the coalition.
“Perhaps now, MP’s and other Kiwis will pay more attention the following points made in our open letter at that time:
“New Zealand may be no warmer in 2006 than it was in 1800. According to temperature records from NIWA, New Zealand has
not experienced significant warming in the last 50 years.
Figure 1
“Figure 1 (top) was taken from NIWA's website. The extreme warming spike around 1998 was the result of the El Nino
southern oscillation, a natural climate event. Shortly after our Coalition drew attention to this graph in May 2006, it
was removed from the NIWA website and replaced by Figure 2 (lower), including the new black dotted trend line 1900-2005
which emphasises for readers the steeper warming at about 1 degree for this particular 106 year period. It is clear to
the eye that the entire 1853 to 2005 period shows a total net ‘warming’ of less than three-quarters of 1 degree warming
over the 153 years.
Figure 2
“We note in Fig 2 that the addition of data for 1853-54 and the alteration for 1857, from a period when temperature
records in New Zealand were certainly very sparse, has the effect of slightly increasing the warming in Fig 2 compared
to Fig 1.
“This selective use of data to produce a desired result is one of the major problems in the current global warming
debate. The problem is compounded when the data used is not released into the public domain, so that calculations can be
checked by independent scientists. NIWA and other government agencies should be required to make free, public release of
any climate data that they use as the basis for advice to government.
“In any case, the revised graph shows a movement of from -0.5oC to +0.2oC in 100 years, a total net ‘warming’ of less
than three-quarters of 1oC that is hardly catastrophic. Note that the addition of the unusually low temperature just
after 1850 - when temperature records in New Zealand were probably poor - has the effect of increasing the apparent
warming. Interestingly, the fifty years prior to 1902 shows a gradual decline in temperature of approx 0.4oC, suggesting
that the New Zealand climate in the first half of the 1800's may have seen periods not so different from that of recent
decades.
“There's some warming and some cooling, but on average no change. The temperature records for Christchurch show a peak
in 1915 greater than 1998, a cooler period from 1925 to 1955, but no overall change since 1905. The Wellington records
available only up to 1989, shows a high peak in 1918 and 1922, a cooler period between 1925 and 1955, but no overall
change since 1880. 1940 to 1982 was cooler than 1880 to 1922,” the relevant section of the open letter concluded.
The coalition states that the contradiction between what temperature records say and claims by the present government
that there is sufficient “warming” as to justify stringent and costly impositions aimed at limiting emissions of carbon
dioxide, is one of the principal reasons the coalition called for a Royal Commission to inquire into the whole climate
change issue as it could affect New Zealand.
(The complete text of the open letter is available on the coalition’s website: http://www.climatescience.org.nz
ENDS