Mr P Otway's letter regarding global warming (February 25) roused me to mention a few things about the temperature record. We see and hear statements such as 'the hottest in living memory” or 'the warmest month in ten years”, etc.
As a retired operational forecaster I know most Met Services state temperature in specific ways. All record the Maximum and Minimum for the day. A really hot 26 can be offset by a very cool 12.
Is New Zealand getting hotter? Probably not much if at all, but you can research this yourselves. All temperature records are in the Dominion or the Herald. NZ Met Service records go back to 1886.
What's disturbing is many of the recent temperature records may be unreliable due to the inadvertent violation of siting requirements.
In the US, a recent survey found 89 per cent of the stations failed standards. Examples: a station near a building complex where one didn't exist before, or a station near the exhaust of an air conditioning unit, etc. So what do climate folk do? They adjust the recorded values. They do it all the time now. NIWA does it. Do they adjust correctly? There is a law suit in the NZ courts regarding this.
Another point: two-thirds of the globe is water without a dense network for monitoring. It's difficult to get reliable data. Good news is that satellite measurements are increasing data points. However the issue is only a matter of a few degrees and expensive conclusions can be drawn from adjusted data that may be in error and incomplete.
David Sapiane, Tauranga.