New Zealand’s leading right wing blogger, National Party spinmeister and opinion poll guru David Farrar, this morning allowed himself the luxury of a rant about the New Zealand Herald‘s coverage of a new paper on sea level during the late Pliocene. In a post teasingly titled “Alarmist bullshit“, he manages to demonstrate his rudimentary grasp of the facts, misunderstands the real story behind the new research, and ends up shooting himself in the foot. Here’s David in full flow:
Anyone who thinks public policy today should be based on a forecast of what the climate might be in 5,000 years is nuts. Look at how the world has changed in just 100 years let alone hundreds or thousands. Hell in 1,000 years we may be living on Mars.
The Herald should be ashamed for saying that the projected increase could “dramatically transform” our coastal boundaries. A change over 1,000 years+ is not dramatic. It’s like saying the separation of Gondwana was dramatic.
20 metres is a lot of sea level rise. Here’s what 20 metres would mean for my nearest city, poor old quake-plagued Christchurch, courtesy of the Firetree sea level rise calculator. The central business district is under water, the new shoreline well to the west. At a rough guess, I’d say 80% of the city is flooded, and Banks Peninsula is an island once more.
I think that can be reasonably described as a dramatic transformation of the South Island coastline, even if it does take 1,000 years to happen. DPF might like to note that coping with two metres per century sea level rise is nobody’s picnic. But his misunderstanding runs deeper…
His first mistake is in his opening paragraph:
Some people doubt temperatures are rising at all, But I do think there is a warming trend, of which greenhouse gas emissions are at least partially responsible. However even the IPCC say that the maximum rise in sea levels by 2100 is 59 cm. This is a 2007 projection. Since then some media have quoted extreme claims beyond that, but I prefer to put credence on the IPCC projections. The IPCC process is far from perfect, but they tend to produce reasonably sane figures.
The IPCC’s Fourth Report does not say that the maximum sea level rise by 2100 is 59cm. It says that the maximum modelled sea level rise is 59 cm, specifically “excluding future rapid dynamical changes in ice flow”. The “extreme claims” in “some media” since then reflect the advancement of our understanding of those dynamical ice sheet flows — the rapid increase in ice mass loss from the Greenland and West Antarctic ice sheets in particular, the subject of the paper that prompted the Herald story. The IPCC’s fifth report is due out towards the end of next year, and it is certain — based on the recent literature — that the AR4 numbers will be revised upwards.
Isaac Davison’s Herald story is actually a good account of the new paper ((Miller, K.G., Browning, J.V, Kulpecz, A., Naish, T.R., Kominz, M., Rosenthal, Y., Cramer, B.S., Peltier, R., Sosdian, S., Wright, J.D., (in press). The high tide of the Pliocene: Implications of a 25-20 m eustatic peak for Antarctic glaciation. Geology, here)), and it’s obvious that he’s taken the time and trouble to speak to Victoria University’s Tim Naish, one of the authors. He quotes Naish as saying it was “well-established that oceans would rise one metre this century”. Perhaps DPF didn’t read that far…
However, both the Herald and Farrar fail to make the key point that this study illustrates so well. If current carbon dioxide levels commit the planet to a further 2ºC warming and 20 metres of sea level rise (however long it takes to get there), then prudent public policy means that we have to reduce the amount of CO2 below today’s levels to avoid visiting catastrophic sea level rise on future generations. This is essentially the point that Jim Hansen has been making, and why 350.org adopted the number they did.
Put simply — in terms DPF can understand — the import of this new study is to confirm that New Zealand government policy on carbon emissions is ludicrously out of touch with the state of our understanding of the planet’s climate system. Sadly, NZ is not alone in this. Global policy settings are just as far out of line with reality, and the international community shows little appetite for addressing the real scale of the problem. By aiming only for what they deem politically possible, they commit the world to disaster.
I suppose we can forgive DPF for not keeping up with the state of research in this field — he is, after all, a political animal first and foremost, and one not averse to feeding the ravening denialist hordes that haunt his blog’s comments — but you might expect someone who expects to be taken seriously when discussing public policy to be a little more humble when commenting out of his area of expertise.
“DPF might like to note that coping with two metres per century sea level rise is nobody’s picnic.”
Exactly. As a climate scientist reminded me a couple of years ago, people tend to take false comfort from figures like “x metres by 2100” – and lack of appreciation of the relentlessness of the change.
Farrar should confine himself to politics. He is a smug self-satisfied mouthpiece for the National Party, popular with the ignorant babblers that comprise the talkback hosts (“Squawk ZB” is the appropriate term) at the Radio Network. Leighton Smith is the worst perhaps, as he talks about climate issues more than the others.
That is why people pushing for immediate action on Climate change are failing so miserably.
If public policy is to believe this stuff, then isn’t this the ideal opportunity to abandon Christchurch, or at least the eastern suburbs?
By the way, I have a property 200m from the sea in this area, It is a probable demolish and rebuild, so I have somewhat of a personal interest in this topic.
The Christchurch rebuild certainly needs to factor in current expectations of sea level rise, not least because my understanding is that the land to the north of the estuary dropped tens of centimetres after the February quake and tidal flooding is already becoming a problem in some areas.
I wouldn’t advocate moving the whole city inland – yet. I have to hope that the world will see the wisdom of getting CO2 down to 350 ppm (probably lower, given the research discussed above), and that this will be done before Greenland and West Antarctica are irrevocably committed to major melt. And if we don’t, it’s likely that other aspects of climate change will present more pressing short term problems.
Having said that, have a look at what 1 m does to the Mekong Delta. The Asian megadeltas are crowded places, and vulnerable to small amounts of SLR.
You are correct that parts of the city dropped several 10s of cm. This is most readily visible in the area around the former Pleasant Point yacht club near the South Brighton bridge. The club house was completely engulfed and has now gone.
Conversely, my property was raised by about 50cm, I am told. This is only 2km from the former yacht club, so there was a tilt rather than a uniform drop in the land level.
I guess potential sea level rise and other environmental factors all need to be factored into the long term planning for the city.
ChCH planners should probably treat 1m as the minimum expected SLR by 2100. They should double that to provide some sort of “safety margin” given current knowledge. That might suffice for buildings and infrastructure with a <100 year expected life, but the sea will continue to rise for some time afterwards even if we do manage to follow an overshoot emissions trajectory and get CO2 down to 350 or below. But we'll know a lot more in 20-30 years...
Worth remembering that during the Eemian, sea level was about 6m higher than today with CO2 at 300 ppm or thereabouts. It might be wise to treat that figure as a starting point for long-lived infrastructure such as a CBD.
I’m skeptical about Firetree’s 20 m coastline, it may be further inland. A check of the 4m estimate shows only the far eastern flooding, but Google Earth puts the steps of the Cathedral at 4 m, confirmed by the fact that the high tide mark on the Avon is between the Kilmore & Barbados St bridges, with quite a rise to the Square.
I think it would be very foolish to build anything in New Christchurch that can’t be loaded onto the back of a truck and moved inland. Especially given Our Glorious Leaders’ current attitudes.
Just checked the figures with Google Earth, the 20m contour does pass roughly thru the Burnside-Hornby-Prebbleton line. The rise between the CBD and the western suburbs is steeper than I thought.
However Firetree’s images below 20 m are a bit random. Or maybe GE’s are, it puts the water at Kerr’s Reach at 5m, which would require some spectacular tidal rises at the Estuary.
Whatever, a cardboard cathedral may be a bloody good idea.
The Firetree (and google) height data is from satellite radar, which bounces off tree tops and roof tops, so most things on the map are a couple meters above where they really are other than in open grassland and water bodies.