TVNZ, you are telling porkies

• Guest post •

— by John McLean

Beyond a joke — this must stop!

It’s Tuesday evening and TV One isn’t improving. This time it claims that climate refugees will be leaving Kiribati due to rising seas, caused by man-made climate change, and heading to New Zealand where, surprisingly, the new government is preparing to issue ‘climate refugee’ visas.

In 2005 the United Nations Environment Program (UNEP) and the United Nations University predicted that 50 million people could become environmental refugees by 2010, fleeing the effects of climate change.1 Contrast that figure with the single known instance of a ‘climate refugee’ residency application in New Zealand four years ago, an application that was rejected by the court.

With that in mind, let’s examine TV One’s claims.

The Permanent Service for Mean Sea Level (PSMSL) database shows that the only tidal gauge operating in Kiribati is at Betio (Lat. 1.365 S, Long. 172.933 E), on the island of Bairiki, which is ENE of Nauru, almost due north of New Zealand. It has only been operational since 1993 and data for nine months of the first two years are missing, making all data over that period pretty useless.

The sea level trend from January 1995 to December 2016 is 4.7mm/year but that period includes the very abnormal super-strong El Nino of 1997-98, which saw sea level at Betio fall about 250 mm and only slowly return to its old level.

If we skip the period of the El Nino and the slow recovery and calculate the trend from January 2000 to December 2016 it’s just 1.9mm/year. At that rate it will take over 50 years to exceed 100mm, which is about the width across the palm of an adult male’s hand. A mass exodus to New Zealand or anywhere else any time soon seems highly unlikely.

The other thing about Betio sea level is that it corresponds quite well to the Nino 3.4 index to the El Nino-Southern Oscillation (see graph) a few months later, suggesting that the ENSO is a very large influence on sea level there. There’s no conclusive evidence of any human influence on the ENSO so Kiribati sea level change seems entirely natural.

Quite good correlation between sea level at Betio and the Nino 3.4 index to ENSO a bit later – which has nothing to do with us.

TV One’s claim about man-made climate change causing rising seas that will lead to climate refugees fails on two counts:

  1. The rate of sea level rise is trivial.
  2. The evidence suggests other causes for sea level change.

If the media is going to report on climate change it needs to find journalists or advisors who know what they are talking about and how to use the available data.






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