Sea level rise and planning guidelines

If we are truly informed by sound science we will understand that “doing our fair share” is not a sufficient response in a world falling well short of doing what is necessary to prevent deeply disruptive levels of warming.

During a question-time exchange in Parliament a few days ago Green MP Kennedy Graham (pictured) put this question to the Minister for Climate Change Issues:

Is he concerned by a recent report of an international team of scientists that, even with a two degree Celsius rise in average global temperature, future generations could face sea levels of up to 12 to 22 metres higher than at present?

Kate Wilkinson, the Minister of Conservation, replied on behalf of the Minister for Climate Change Issues:

Yes. The estimates of sea level rise in this report are in line with estimates from the science community over the past few years. But I note that the author himself puts these estimates in context by stating that such changes could take centuries or millennia and that “The current trajectory for the 21st century global rise of sea level is 2 to 3 feet …”.

Graham’s follow-up question pointed out that the current government guidelines for councils for sea level rise for 2100 are lower than the level estimated by scientists and asked whether the need for correction would be admitted.

I wrote about the guidelines three years ago. They recommend using a base sea-level rise of 0.5 m by the 2090s for planning and decision timeframes, but suggest an additional assessment of the consequences of a rise of at least 0.8 m.

It seemed odd advice at the time. Why assess consequences for 0.8 m but plan for only 0.5 m?

Anyway, the Minister in his answer to Graham seized on the higher figure as representing the government recommendation (no mention of the 0.5 m) and claimed it was in line with the scientific report Graham referred to, on the grounds that the lead author spoke of the current trajectory for the 21st century sea level rise as between 0.8 m and 1 m.

There is an element of evasion in this reply. If the government’s maximum guideline is the scientists’ minimum it can hardly be said to be in line. One metre would surely need to be the guideline before the government could claim to be in line with the report’s lead author.

However Graham pressed the matter with a question in relation to the rebuilding of Christchurch, this time quoting scientific assessments of sea level rise by 2100 ranging between 0.9 m and 1.6 m and asking whether the Minister would act to support the proposition that the city rebuild should allow for a possible 2m sea level rise.

The Minister stood firm by the guidance that the government has already provided, and suggested that the member make his own representation to local councils “if he feels that any specific factors do need closer attention”.

Nick Smith is no longer the Minister for Climate Change, but he has rather contemptuously declared in the past in relation to this question, “The hovernment is not going to consider adjusting its policy every week.”

Maybe not, but how foolish would it be to stick with a figure for sea level rise which does not represent the latest scientific understanding? Graham in posing his question about Christchurch referred to the fact that a city’s life cycle is over centuries. That lends added weight to his contention that the rebuild should allow for the possibility of a 2-metre rise.  It deserved better than the deflection it received from the Minister.

Sea level rise is a stark consequence of global warming for governments to pay attention to. The Minister’s reply to Graham’s initial question seemed to be taking comfort from the fact that the very large rises may take centuries or even thousands of years to develop, as if that somehow relieved us of responsibility. It doesn’t. To knowingly contribute to such drastic consequences for generations even centuries away is deeply unethical; if we value humane and decent principles we can’t wash our hands of those consequences.

There’s a kind of desperation in the way the government claims to pay attention to the science yet plumps for the lowest predicted level of sea level rise. Imagine if in the reconstruction of Christchurch it was decided to require buildings constructed to withstand earthquakes only in the lower range of severity. In the short term of the century ahead we should take the full range of predicted sea level rise into account and allow for the higher possibility, not the lower. The government’s current guidelines for councils should be amended accordingly.

The more general question from Graham which concluded the exchange in the House elicited a response which indicates the complacent frame of mind behind the reluctance to reconsider sea level rise guidelines. Graham asked how, in the light of the recent OECD projections that without new mitigation policies the world is headed for substantial increases in emissions, the Minister can repeatedly assure the House that that every government, including New Zealand, is doing enough to combat climate change.

The response was the familiar mantra:

The member is correct: climate change is a global issue, and a global response is needed. New Zealand is committed to fulfilling our international responsibilities. New Zealand is a small player, but we are doing our fair share, and our guidance will continue to be informed by sound science.

There is perhaps a glimmer of hope in those final four words, because if we are truly informed by sound science we will understand that “doing our fair share” is not a sufficient response in a world which is collectively falling well short of doing what is necessary to prevent deeply disruptive levels of warming.

This post originally appeared on Sciblogs.