Archive for the ‘Climate change’ Category
Time to stop hiding behind warming trends
By Roger Jones, Victoria University
Dr Rajendra Pachauri, head of the IPCC, has reportedly acknowledged to Graham Lloyd of The Australian, that there is a “17-year pause in global temperature rises”, a fact that apparently has been suppressed in Australia. Dr Pauchauri endorses debate, saying that people had a right to question the science, whatever their motivations.
But according to Lloyd, Pachauri’s views contrast with arguments in Australia that views outside the orthodox position of approved climate scientists should be left unreported.
Am I an “approved” climate scientist? because I don’t hold that view, nor do I know any who does. What we would like, though, is for science to be reported as science and for opinion to be reported as opinion. And for all reporting to be accurate.
Lloyd makes this claim: unlike in Britain, there has been little publicity in Australia given to recent acknowledgement by peak climate-science bodies in Britain and the US of what has been a 17-year pause in global warming. Britain’s Met Office has revised down its forecast for a global temperature rise, predicting no further increase to 2017, which would extend the pause to 21 years.
This is the Met Office’s latest five-year forecast shown below. Skeptical Science reports the Met Office saying: the latest decadal prediction suggests that global temperatures over the next five years are likely to be a little lower than predicted from the previous prediction issued in December 2011. We’re in the midst of a period of La Niñas, which have a slight cooling effect, as do rising sulphate emissions in Asia. But look at the blue line – do my eyes deceive me? Is it level with the previous black line? It’s warmer? Perhaps Lloyd’s computer has a tilt to the right that makes increases look level.
The Met Office predicts record global mean temperature over the next five years – now that’s news.
News Corporation sells roughly 70% of the newspapers in metropolitan Australia, and its readers are subject to this kind of fudging on a regular basis. It’s no wonder some “approved” scientists are frustrated.
But that’s not the only thing that frustrates me. It is also time to challenge what Lloyd calls the orthodox position of climate science.
Climatology needs to stop hiding behind long-term trends and explain what is in plain sight, and why variations in the rate of warming might be important. I’m working with colleagues at the moment on a National Climate Change Adaptation Research Facility project called Valuing Adaptation to Rapid Change and we’re looking at the economics of rapid change. Non-linear behaviour in climate driving extreme events has the potential to really hurt us.
The first thing to bear in mind is that a trend line is a model. A warming trend is not a theory of how climate changes. If a complex, non-linear system fails to follow a trend, look at the model to see whether it represents the theory sufficiently well.
In a nutshell, the theory says greenhouse gases act like a blanket, trapping heat near the surface. This creates a radiation imbalance at the top of the atmosphere. The earth system warms to return this balance by increasing the heat escaping from the top of the atmosphere so that energy out equals energy in. This is a slow process, taking centuries, because the ocean has to warm sufficiently to support a hotter atmosphere. The scientific confidence in this aspect of climatology is extremely high. A simple trend line is sufficient to measure this process.
But on decadal time scales, the trend-line model fails. Most of the heat trapped in the earth system goes into the oceans. The top 700m of ocean increased in heat content from 3 x 1022 Joules in 1997 to 10 x 1022 Joules in 2010, in a highly non-linear manner, due to mixing rates between the surface and deep ocean. The atmosphere holds as much heat as the top 3m of ocean, about 0.4% of the heat content above. Why on earth then, with highly non-linear processes in the ocean, would we expect a gradual warming trend in the atmosphere?
A paper I published last year shows that most of Australia’s warming occurred in two episodes, one in the late 1960s to early 1970s, when south west WA rainfall also decreased, and the other in 1997-98. The other finding was that most of this warming was anthropogenic. On decadal timescales, step and trend is a much better model for explaining warming than simple trends.
To me, the graph above makes perfect sense: mild trends separated by an instantaneous rise of about 0.3°C. By ignoring non-linearity and projecting future climate change as simple trends, orthodox science is doing us a great disservice. We have not yet woken up to the recent non-linear increases in heatwaves and fire danger in Australia let alone planning for more such changes in the future. The same goes for floods.
It’s time to stop defending orthodox science by hiding behind simple trends and come to grips with the fundamental non-linearity of climate change. That’s the risk we need to mitigate, adapting to changes that can’t be avoided.
Roger Jones receives funding from the National Climate Change Adaptation Research Facility. He is affiliated with Climate Scientists Australia and the IPCC.
The Climate Vulnerability Monitor 2nd Edition, released today, reveals that climate change has already held back global development and inaction is a leading global cause of death. Harm is most acute for poor and vulnerable groups but no country is spared either the costs of inaction or the benefits of an alternative path.
Key findings include estimates that carbon-intensive economies and associated climate change are responsible for five million deaths a year, 90 per cent of them related to air pollution, according to an Agence France-Presse report.
“Failure to act on climate change already costs the world economy 1.6 per cent of global GDP amounting to $US1.2 trillion ($A1.16 trillion) in forgone prosperity a year,” said the report, produced by the DARA research centre and released at the Asia Society in New York.
In addition, “rapidly escalating temperatures and carbon-related pollution will double costs to 3.2 per cent of world GDP by 2030.”
According to the report, “unprecedented harm” is being inflicted on humanity.
However, tackling climate change’s causes would bring “significant economic benefits for world, major economies and poor nations alike,” the report said.
The report was published by DARA, and compiled by the World Vulnerability Forum. 45 Mb download of the entire report is here and the page where parts of the report can be downloaded is here - data can be downloaded as well.
It contains complex information and graphics, so is not easy to decipher. Hopefully, I’ll have time to digest the main points and summarise them here. Hat-tip Rob Gell.
Interesting ice-core temperature results from James Ross Island on the Antarctic Peninsula (AP) that points to recent and rapid warming that is unusual and of concern (sourced from Crikey who find its unusual nature alarming). The Australian reports (via Graeme Lloyd) that while unusual, the warming is not unprecedented relative to natural variation. Lloyd also includes a quote that is neither in the paper or the press release, and a bogus assertion arising from a misunderstanding of the purpose of the research. I have enquired from the authors if they were the source of Lloyd’s quote. Update – they have replied: see below.
So, how concerned should we be about the results? From the press release:
Results published this week (Nature paywall) by a team of polar scientists from Britain, Australia and France adds a new dimension to our understanding of Antarctic Peninsula climate change and the likely causes of the break-up of its ice shelves. Read the rest of this entry »
No, not an exotic Hungarian sandwich, but The Grauniad has an excellent 50th anniversary review of Kuhn’s The Structure of Scientific Revolutions written by John Naughton in their Sundy paper. In a total paradigm shift, the comments aren’t totally trolltown, either. See also, Howard Sankey on the The Conversation.
Before Kuhn, our view of science was dominated by philosophical ideas about how it ought to develop (“the scientific method”), together with a heroic narrative of scientific progress as “the addition of new truths to the stock of old truths, or the increasing approximation of theories to the truth, and in the odd case, the correction of past errors”
Warmer oceans, tropical species being found further south, decline in temperate species, the first signs of CO2 effects on shell production in Australian waters …
These are a few of the headlines from the Marine Climate Change in Australia, Impacts and Adaptation Responses 2012 Report Card (download pdf). Put together by the Marine Biodiversity and Resources Adaptation Network (NCCARF), Fisheries Research and Development Corporation, and CSIRO’s Climate Adaptation Flagship. The reporting comprehensive, covering the report card itself and six chapters on marine climate and thirteen on marine biodiversity. Alistair Hobday, summarising the report card on The Conversation.
Here’s a summary with some of my own conclusions about observed and projected changes. The latter you can take or leave as they’re based on my personal views about how climate changes. For recent and near future changes, I place a greater emphasis on how climate is likely to change rather than by how much. This places the emphasis more on the diagnosis and understanding of change rather than prediction. There’s a fair bit in doing this, so amongst other things I’m into today (like gardening, cooking and cleaning), I’ll update these sections as I go (Sunday 11 am, SST; Wednesday, SLR). Read the rest of this entry »
The recent VCCCAR Annual Forum featured an industry roundtable breakfast, chaired by Anne Barker of City West Water, to discuss industry and adaptation to climate change. The roundtable was attended by a couple of dozen people from industry, public policy and research. The discussion was really interesting, with industry representatives talking about the opportunities they were pursuing, how targeted R&D could keep down product prices (e.g., in housing construction) and what kinds of supporting policy they would like to see. There are clearly lots of opportunities for collaboration between research and industry but they won’t be successful without close cooperation.
As part of the roundtable, an Industry Roundtable Context Paper (pdf download) was prepared by Celeste Young and myself. We tried to keep it simple and direct. It’s scope is also limited to Victoria, but we hope it also is relevant in a broader context. The main points are (not rocket science!): Read the rest of this entry »
The following article was written for an online publication but never made it out the door. It describes the recent Victorian Centre of Climate Change Adaptation Research Annual Forum. It seems a pity to waste, so here it is. Co-written with a colleague, Celeste Young.
When the Intergovernmental Panel on Climate Change started researching adaptation in the early 1990s, the relationship between science and policy was viewed differently to how it is today. The IPCC’s brief was to offer policy-relevant, not policy-prescriptive advice. Policymakers would take scientist’s findings on climate change and impacts and develop adaptation policy to manage those impacts. These findings were contained in a report handed over from the science to the policy community every five years or so.
Times have changed. Adaptation scholars looked at this methodology (automatic download of pdf) and said “IPCC, You’re doin’ it wrong!” Adaptation is a social process. The focus has therefore shifted from getting better predictions out of science to getting a better understanding of decision-making under climate change. Sure, adaptation needs information on how the climate may change but adaptation decisions are made using information from many other sources; such as “what changes are we seeing in markets, policy, society and the environment?” And, most importantly, “what are the goals of people doing adaptation?”
An excellent briefing from Paul Rogers of the Oxford Research Group on food security and climate change is updating the current global situation with respect to recent climate events (Hat tip to Jamie Doughney). I’ll reproduce it below after making a few comments.
Most of the briefing concentrates on the conditions of the 1974 food crisis to add a historical perspective. Globally, the US and North America is in the second year of drought, looking at greatly reduced maize production and other other crops. The southwest Indian monsoon is somewhat late and currently at 17% below the 50-year average after a poor year last year. The Horn of Africa is in a delicate recovery stage after last year’s disaster, and efforts to build resilience in the region are ongoing. A recent report from scientists at the UK’s Met Office and the USA’s National Oceanographic and Atmospheric Administration (NOAA) found that the number of below average rainy seasons in East Africa could have been attributable to warming in the Indian and Western Pacific Oceans.
Rogers states that economic growth has been patchy, so that the proportion of people under food stress has not changed greatly since the 1970s. This time around though, he nominates climate change as making a significant contribution to that stress. I agree. One part of that is the asymmetric impact of warming on land affecting drier regions. This is pretty well known. The other is that he suggests climate change is accelerating:
The loss of Arctic sea in recent summers has exceeded forecasts using climate modelling and some recent events have been startling in their intensity, including the extent of the thawing of surface layers of the Greenland ice cap during the early part of July.
This is because climate change is strongly non-linear, and there is increasing evidence that the world, or at least much of the northern hemisphere, is in a warming episode similar to that experienced in 1997-98. The idea that extremes should change gradually on a smoothly changing mean climate is seriously wrong, and if the world continues to adapt based on that assumption, millions of people will continue to be at risk through insufficient adaptation efforts.
I’m champing at the bit to get back to this research because I use different methods to those of mainstream climate science (but also have a truckload of other work to do). However, both lines of research are pointing to a strong climate change signal in recent extreme events, thereby increasing scientific confidence in its conclusions.
Rogers’ briefing is reproduced below.
After me getting an op-ed in The Age representing real climate science and policy, it’s time for some asshattery, c/- both the Melbourne Age and the Sydney Morning Herald. The Fairfax press has decided to redress the balance of knowledge with some agnotogeny* from Dr David Evans. From his tagline:
Dr David M. W. Evans is a mathematician and engineer who consulted full-time for the Australian Greenhouse Office (now the Department of Climate Change) from 1999 to 2005. He says he changed from being a warmist to a sceptic after ”evidence supporting the idea that CO2 emissions were the main cause of global warming reversed itself from 1998 to 2006”.
Oh purleeze. Read the rest of this entry »
A couple of my recent forays into the media have provoked comment below the articles themselves and in emails sent querying particular points. They are worth unpacking because they reflect on the different between the straight communication of science and framing risk.
One was in reference to a recent op-ed in The Age. In it, I said:
If people accept the 0.0038 and 0.02 degree benefits as valid then they also accept the science behind a 5.3 degrees warming for business as usual (As in the emission scenario created by Treasury for the 2008 Garnaut Review). Who wants to live in a world warming by 5 degrees or more? Major food crops could not be grown in many parts of the world, projected sea level rise would be tens of metres, most of the shelled species in the ocean would not survive, ecosystems would be disrupted as the pace of change outstripped their ability to adapt and millions to billions of people would lose environmental security leading to mass migrations never before seen.
That prompted an email from an earth scientist wanting to know what peer-reviewed reference I was using for the projected tens of metres of sea level rise. I sent back this now famous diagram and a note saying that I wasn’t putting it on a timetable. He then replied suggesting that people could be misled into thinking that the date was 2100 (because that was tied to the two temperature measures) and that I was being alarmist. Because it would take thousands of years to be realised. Read the rest of this entry »