The encroaching sea: new NZ sea level rise maps

This guest post is by Jonathan Musther, who has just published an amazing series of highly detailed maps projecting future sea level rise scenarios onto the New Zealand coastline. If you live within cooee of the sea, you need to explore his maps. Below he explains why he embarked on the project.

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The effect of 10m sea level rise on Christchurch: say goodbye to St Albans, prepare to paddle in the CBD. Full map here.

For humans, sea-level rise will almost certainly be the most directly observable effect of climate change, and specifically of global warming. As the climate changes, many of the effects will be subtle, or if not subtle, they will at least be very complex. Summers may be warmer, or cooler; we may experience more rain at some times of year, and less at others; tropical storms may increase and they may be sustained further from the equator, but all of these changes are complex, and not necessarily obvious against the background complexity of any climate system. In contrast, there is something obvious and unstoppable about sea-level rise, there is no question that it will send anyone in its path running for the hills.

For some time I have been involved in searching for land appropriate for specific uses such as arable farming, water catchment, and off-grid living. When searching for land in this way, there are many, many criteria to consider, and of course one of these is potential future sea-level. Using GIS (Geographical Information System) software, and elevation models of the New Zealand landscape, it is possible to visualise sea-level rise, and select sites accordingly. Naturally, the next question is what sea-level rise to consider. It is possible to place an upper-limit on sea-level rise – after all, there’s only a finite amount of ice that could melt – but beyond that, we’re limited to informed guesswork.

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25m sea level rise: a sunken city and Banks Island. Full map here.

What is the maximum possible sea-level rise? It depends who you ask. Many sources place the maximum potential sea-level rise at around 60-64 metres, but these figures are rarely referenced, and don’t concur with the latest research. Other sources place the figure at around 80-81.5 metres, and while this appears to be well referenced and researched, it is based on work that is somewhat out of date. The best estimates I’ve been able to locate, based on recent measurements (and lots of them) are around 70 metres, but quite what the margin of error is remains uncertain. Of course, when considering future sea-level, we must remember that here in the South Pacific, we will likely experience increased numbers of more powerful tropical storms, with associated storm surges.

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At 80m, West Melton is a seaside township. Full map here.

The maps I created showing sea-level rise for the whole of New Zealand depict rises of 10, 25 and 80 metres. I have certainly received criticism for not focussing on more modest sea-level rises (e.g. 1 or 2 metres), but there are some good reasons for this: firstly, the resolution of the elevation models of New Zealand do not allow accurate predictions of such small rises. Secondly, larger sea-level rises pose a huge threat, and are therefore worth considering. I made a point of avoiding time frame predictions when producing the sea-level rise maps, partly because the time frame is largely irrelevant (if 80% of our homes are flooded, it’s bad news, no matter when) and partly because the range of expert estimates is huge. Study after study shows that we have underestimated ice-sheet instability, and it is almost universally accepted that large sea-level rise will be a consequence. Unfortunately, most studies place this sea-level rise at some unspecified time in the future – when, we’re not sure, but it’s far enough away that we needn’t worry…

So is a 10 or 25 metre sea-level rise likely? Unfortunately, the broad answer is yes. The Greenland, West and East Antarctic ice sheets are showing growing instability, and many researchers agree that they may have past a ‘point of no return’. Remember, the Greenland ice sheet alone, if completely melted, would lead to approximately a 7 m rise in global sea-level. Of course, we return to the issue of when this is likely to happen, and on that, the jury is out.

I firmly believe that to be good scientists, we must investigate the possibility of large sea-level rise, and its consequences. The time frame is unclear, the absolute rise is also unclear, but there really is something unstoppable about rising oceans. We are now well outside the sphere of collective human experience and expertise, and we should be very careful to prepare, as best we can, for a range of scenarios.

Climate Shock

Uncertainties attend the predictions of climate science, as the scientists themselves are careful to acknowledge. Reluctant policy makers use this uncertainty to support a “wait and see” response to climate change. Prominent American economists Gernot Wagner and Martin Weitzman in their recent book Climate Shock: The Economic Consequences of a Hotter Planet are scathing in their condemnation of such a response. They translate “wait and see” as “give up and fold” and call it wilful blindness.

Their own response to the uncertainty surrounding climate predictions is to ask what the worst case scenario looks like.

Here’s what you get: about a 10 percent chance of eventual temperatures exceeding 6 ° C, unless the world acts much more decisively than it has.

This isn’t a figure they’ve made up for themselves. It’s based on IPCC prediction ranges and on the International Energy Agency’s interpretation of current government commitments.

It’s clearly a catastrophic scenario, but with a 10 percent chance of happening it must play a prominent part in our thinking and planning. We take out fire insurance on our homes with a much lower than 10 percent chance of their burning down. It’s called prudence, and most of us don’t think twice about the precaution of insurance.

Continue reading “Climate Shock”

DomPost denier debacle: science has the last word

The Dominion Post, which blotted its editorial copybook last week by publishing a factually incorrect and highly misleading opinion piece by climate denialists, has today published a heavyweight reply by three of NZ’s top climate scientists — David Wratt, Andy Reisinger and Jim Renwick ((David Wratt is an Emeritus Climate Scientist at NIWA, an Adjunct Professor in the NZ Climate Change Research Institute at Victoria University, and a Vice Chair of Working Group 1 of the IPCC. Andy Reisinger is Deputy Director (International) of the New Zealand Agricultural Greenhouse Gas Research Centre and served as coordinating lead author in the most recent IPCC report. James Renwick is a Professor of Physical Geography at Victoria University of Wellington and served as a Lead Author on the last two IPCC Reports.)). Headed “Human role in climate change is clear”, the article is clear about climate reality:

Human influence on the climate system is clear and growing, and impacts are evident on all continents. If left unchecked, climate change will increase the likelihood of severe, pervasive and irreversible impacts for people and ecosystems.

We do have options to reduce risks by reducing greenhouse gas emissions and adapting to some climate change, but time is running short if we want to limit changes to manageable levels. Ignoring or misconstruing the overwhelming evidence is not a responsible risk management strategy.

It’s not clear whether the DomPost plans any further response to the rubbish they printed from Bryan Leyland and Bob Carter, but the editorial team at the newspaper would do well to reflect on the approach to the subject adopted by Guardian editor Alan Rusbridger, introducing an important new series of features in that paper:

For the purposes of our coming coverage, we will assume that the scientific consensus about man-made climate change and its likely effects is overwhelming. We will leave the skeptics and deniers to waste their time challenging the science. The mainstream argument has moved on to the politics and economics.

Precisely. Rusbridger — who is retiring after 20 years as editor — wants his newspaper to do justice…

…to this huge, overshadowing, overwhelming issue of how climate change will probably, within the lifetime of our children, cause untold havoc and stress to our species.
So, in the time left to me as editor, I thought I would try to harness the Guardian’s best resources to describe what is happening and what — if we do nothing — is almost certain to occur, a future that one distinguished scientist has termed as “incompatible with any reasonable characterisation of an organised, equitable and civilised global community”.

That’s what a real newspaper does: takes on the big issues. If the Dominion Post wants to be more than a Noddy book newspaper publishing rubbish from the intellectual heirs to Big Ears, it’s high time it took a sensible approach to the climate debate, and followed Rusbridger’s lead.

Continue reading “DomPost denier debacle: science has the last word”

25 ways the DomPost failed its readers by publishing Leyland and Carter’s climate crap

Carter with his Flat Earth society peers
Carter with his Flat Earth society peers
The Dominion Post, the newspaper of record for New Zealand’s capital city, today gave great prominence to an opinion piece by high profile climate denialists Bob Carter and Bryan Leyland titled Hypothetical global warming: scepticism needed ((On page A7 – opposite the leader. Not currently available on the web, but a scan has been posted on Twitter — see this comment below.)). It’s a “Gish Gallop” of untruths, half-truths and misrepresentations — a piece so riddled with deliberate errors and gross misrepresentations that it beggars belief that any quality newspaper would give it space.

I will deal with the factual errors in a moment, but the DomPost‘s lack of editorial judgement extends well beyond any failure to fact check the article. Carter and Leyland’s expertise on the issue is misrepresented. The newspaper’s readers are not given a true picture of their “standing”. They are in fact paid/sponsored propagandists, way out on the crank fringes. Here’s how Carter is credited.

Professor Bob Carter is an honorary fellow of the Royal Society of NZ. His expertise is in geology and paleoclimatology — deducing past climates from geological records. He has written several books on climate change.

All of that is true ((Except perhaps for the professorship. Carter has no current academic affiliation that I know of, so I wonder why the DomPost is granting him that status? Surely he wouldn’t have misrepresented himself to the paper?)), but it is far from a full picture. In fact, Carter has been a propagandist against action on climate change since the 1990s, with a history of paid work with and for far-right wing organisations in Australia and the USA – including being paid by the notorious Heartland Institute in the US to produce shoddy pseudo-academic publications. In the right wing Australian journal Quadrant, where links to right wing organisations obviously play well, Carter’s credit runs like this:

Bob Carter is an Emeritus Fellow of the Institute of Public Affairs (IPA) and Chief Science Advisor to the International Climate Science Coalition (ICSC).

The IPA campaigns against climate action, and Carter recently starred in its Climate: Change the facts tour around Australia promoting a new propaganda pamphlet. As an adviser to the ICSC — a group attempting to promote climate denial around the world, he works to:

“…directly educate the public about what science, engineering and economics are really concluding about climate change and the downside of misguided plans (e.g., wind turbines, “carbon sequestration”, etc.) to “solve the crisis”. This includes newspaper articles, letters to the editor, radio and TV interviews, public presentations, regular postings on our, and others’, Web sites and use of all forms of popular social media.”

In other words, Carter and Leyland managed to con the DomPost into playing along with their propaganda campaign.

The DomPost credits Leyland thus:

Bryan Leyland is an engineer specialising in renewable energy. He is an accredited reviewer for the IPCC and has contributed several articles on renewable energy technologies to overseas publications.

In fact, Leyland has a long track record of activism against action to reduce carbon emissions. He was a founder member of the NZ Climate Science Coalition and a trustee of the NZ Climate Science Education Trust — formed to bring a court action against NIWA’s handling of the national temperature record. When the case was lost, the trust was folded so that Leyland and his fellow trustees could avoid paying $90,000 of court-ordered costs.

Leyland is notorious in NZ media circles for his attempts to push climate denial. It beggars belief that the DomPost did not know about his track record, and went ahead with publishing an article under his name without prominently noting his role as an activist.

As propagandists, the product that Leyland and Carter are pushing is doubt — a tactic first used by the tobacco industry, but since refined by fossil fuel interests keen to avoid emissions cuts. Leyland and Carter “win” every time a mainstream media outlet gives their views credence by giving them prominence. Newspapers do not regularly provide platforms for cranks, but that is exactly what Leyland and Carter are, as we shall see in a moment.

Continue reading “25 ways the DomPost failed its readers by publishing Leyland and Carter’s climate crap”

Hot Air on TV tonight

Alister Barry’s Hot Air, a superb documentary on the slow and sorry evolution of climate policy and politics in New Zealand is getting its first TV airing tonight on Maori TV at 8-30pm. Alister wrote about his film at Hot Topic back in July, and according to the Listener, it makes for “compelling and absolutely terrifying” viewing. If you miss tonight’s showing, Hot Air will be available to stream from the Maori TV web site. Recommended.

[Update 31/12: Hot Air streaming here.]