Tag: sea level

Christchurch coastal cock up: sea level “expert” de Lange clueless in NBR

IssacCordalBerlinWillem de Lange, the Waikato University coastal processes lecturer and one of the panellists nominated to review sea level rise advice relied on by Christchurch City Council, helpfully demonstrated the true extent of his climate expertise in the National Business Review last week [WebCite]. In an article titled Evidence doesn’t support rapid future sea level rise, written with Bryan Leyland, de Lange demonstrates just how slapdash his approach to the subject really is.

The piece is riddled with errors and misrepresentations. Here’s a selection:

  • The “recent” paper on sea level rise de Lange and Leyland (dLL) reference in their first paragraph is from 2010! The latest Royal Society of NZ climate info was published last month, and is presumably what dLL meant to refer to.
  • The rise in sea level around NZ over the last 100 years is 17cm, not 14cm, according to the RSNZ (page 28 here).
  • dLL claim that climate models are “flawed”, and have failed to predict current temperatures. In fact current global temperatures are more or less bang in the middle of model projections.
  • In discussing tidal gauge measures of sea level rise they refer to a denialist web site, not the primary sources.
  • They reference a textbook on sea level rise, but neglect to point out that it was published 15 years ago.
  • dLL state that the current rate of sea level rise measured by satellite is 3.2 mm per year, with “indications of recent decline in the rate”. In fact it is 3.4mm per year, and shows no signs of any recent slowdown. If anything, there are hints of an acceleration in the underlying rate.
  • dLL claim that satellite measures are “about twice the tide gauge rate”. They’re not. They’re in good agreement. From Trends and acceleration in global and regional sea levels since 1807, Jevrejeva et al, Global and Planetary Change, 2013 (pdf)
    There is an excellent agreement between the linear trends from GSL12 [latest tide gauge data] and satellite altimetry sea level since 1993, with rates of 3.1 ± 0.6 mm/yr and of 3.2 ± 0.4 mm/yr respectively.
  • The latest RSNZ projections are not “much more than anybody else” – they’re based on the IPCC’s AR5 and draw on the current literature. Larger projected future rises are widely used in planning overseas.
  • dLL state: “All the observational evidence indicates that the sea level is likely to rise 0.1 to 0.2 m by 2100.” This appears to be nothing more than wishful thinking. The current SLR rate gives 30cm plus by end of the century as a minimum.
  • There’s strong evidence of increased and increasing ice sheet mass loss in Greenland and Antarctica, which will add significantly to the amount of sea level rise by the end of the century. If we’re lucky, that might only be a metre. If we’re unlucky, it might be a great deal more.

If this were de Lange and Leyland’s only contribution to the debate on how communities should cope with sea level rise, it might be possible to shrug it off as a slapdash attempt at propaganda from a couple of people with a long history of climate denial. But de Lange is getting involved with the Christchurch community’s efforts to deal with this most challenging of issues.

Do Christchurch ratepayers really want to pay for advice from an “expert” who can’t get his facts right, and who is apparently happy to put his name to rubbish? The council should immediately ask for his withdrawal from the panel.

Future sea level rise is a certainty. Dealing with it is going to be challenging for any coastal community. We need a national framework that covers realistic assessments of local risk, and provides a process that allows communities to adapt as equitably as possible as their coastline changes. Trying to ignore or downplay the problem is only going to increase the costs faced by ratepayers and taxpayers in future years. If we allow the process to be contaminated by the input of propagandists we simply set ourselves up for greater losses.

Christchurch’s coastal cock up: review panel padded with climate deniers

IssacCordalBerlinThe long running saga of the Christchurch city council’s attempt to introduce new planning guidelines for suburbs threatened by flooding and sea level rise has reached a new level of absurdity. A five person panel appointed to conduct a second peer review of a key report on coastal hazards includes two high-profile climate deniers with strong links to extreme right wing climate propaganda groups. From Friday’s Press:

The list of experts approved by the council included New South Wales University coastal engineer Dr Ron Cox, Canterbury University coastal studies senior lecturer Dr Deirdre Hart, Waikato University earth sciences senior lecturer Dr Willem de Lange, retired Environment Court judge Shonagh Kenderdine and statistician Dr Keston (sic) Green, of South Australia University business school.

Cox, Hart and Kenderdine are all highly respected experts in the field. However, Kesten Green and Willem de Lange both have long histories of working with and for groups seeking to delay action on climate change. It appears they have been added to the panel as a sop to deniers amongst the coastal residents campaigning against the council’s proposals. Continue reading “Christchurch’s coastal cock up: review panel padded with climate deniers”

Ice melt, sea level rise and superstorms: Hansen on his magnum opus

Why ice sheets may melt faster than expected, and what that could mean for our near future

In this video Jim Hansen provides a “video abstract” of his latest — and longest — paper, Ice melt, sea level rise and superstorms: evidence from paleoclimate data, climate modeling, and modern observations that 2 °C global warming could be dangerous, published this week after a lengthy period in review. He, and his stellar list of co-authors, have also provided an “abbrievated” version of the paper, which I strongly recommend you read.

My abstract is a bit shorter: fresh water from melting ice sheets in Greenland and Antarctica is beginning to change the way that heat moves around in the global ocean, setting up feedbacks that will melt the ice faster. This in turn will lead to much more rapid sea level rise than suggested in the recent IPCC report, and much bigger temperature contrasts between warm and cold oceans in the North Atlantic and around West Antarctica — which will drive the mid-latitude superstorms of the paper’s title.

Not a pretty prospect. And if you think it’s unlikely, consider this. There are already “cold blobs” in the North Atlantic and off West Antarctica, Atlantic storms are becoming much more vigorous , and there are hints of an acceleration in the rate of sea level rise.

Hansen has been right before. I hope, for all our sakes, that this time he’s not.

Fall in San Francisco: Jim Renwick’s AGU report

Jim RenwickI took part in the 2015 AGU Fall Meeting, held at the vast Moscone Center in San Francisco, 14-18 December. As always, it was an absolute cornucopia of everything to do with the Geo/Earth Sciences, from exoplanets to the earth’s core to climate change and science policy, delivered by over 20,000 geoscientists. The Fall Meeting is always a blast, a real mind-expander.

This year, I was committed to chairing sessions first thing on Monday morning and then again on Friday. Monday’s session was “Evaluating Reanalysis: What Can We Learn about Past Weather and Climate?” with my sub-session having a focus on polar regions. The Thu/Fri session was “Precipitation over Mountainous Terrain: Observations, Understanding, Modeling, and Future Prospects”. In between, I soaked up as much as I could, wandering the halls to hear and see fascinating presentations on climate history, science communication, sea ice, and designing climate change musicals for primary school children. Here’s a few highlights, my personal “tip of the iceberg” from this year’s meeting.
Continue reading “Fall in San Francisco: Jim Renwick’s AGU report”

The advice of fools: Newman and Kelly risible on rising seas

IssacCordalBerlinFormer ACT MP Muriel Newman — an extreme right-winger and no stranger to the wilder shores of climate denial — has waded into the debate about sea level rise and coastal hazards in Christchurch in a long-winded and unhelpful article at her NZ “Centre for Policy Research” web site. In many respects, her piece is par for the Hidebound course — full of misdirection, misrepresentation and schoolgirl errors of fact, motivated by a weird world view:

The reality is that unfortunately, carbon dioxide is being used as a political football. When radicals embraced the environmental movement in the seventies, driving out people like Dr Patrick Moore the founder of Greenpeace, they used the climate debate to conceal their real agenda – the global redistribution of wealth.

Newman takes as the text for her sermon a piece by Mike Kelly, a New Zealander who is a professor at the University of Cambridge in the UK. His offering is just as ill-informed as Newman’s — can it really be the case that a professor of technology, whose main expertise is in “advanced electronic devices for very high speed operation”, doesn’t understand the difference between weather forecasting and climate modelling? Perhaps Kelly should read a few introductory texts on climate modelling before pontificating so publicly — and so erroneously.

But what makes Newman and Kelly’s articles so unhelpful to coastal residents in Christchurch and elsewhere is not the parroting of climate denialist tropes, but the conclusion she reaches:

The Christchurch Council – and all other councils around New Zealand for that matter – should base their coastal hazard projections, on what has happened in the past. There is no perfect predictor of the future, but looking at what has actually happened in the past is better than seizing on unreliable models developed by those driving a political agenda.

Let’s do what Newman wants, and forget modelling future sea level rise. Let’s look at the past.

Continue reading “The advice of fools: Newman and Kelly risible on rising seas”