Much of the current debate on climate change hinges on the key issue of what changes have already been detected. In particular, there is the expectation that there would not simply be an overall average warming, but that the number of extreme weather events – heat waves, droughts or floods in particular – would rise. So, when something like the 2003 European heat wave occurs, we are told that such events will become more common in future.
Recently (March 28), the IPCC published a report on the topic (Special Report on Managing the Risks of Extreme Events and Disasters to Advance Climate Change Adaptation or SREX). However, in keeping with the organisation’s somewhat bizarre way of doing things, the Summary for Policymakers, which is all that most people will read, was released last November. At the time, the headlines were quite clear-cut (for example IPCC: Climate impact risk set to increase). Reporting of the latest publication was similar (see Prepare for accelerating climate risks, IPCC says and New report says global warming may be cause of ‘climate-related disasters’). But the report itself is actually more nuanced.
For example, take the following key conclusions summarised in the press release:
· ° Medium confidence in an observed increase in the length or number of warm spells or heat waves in many regions of the globe.
· ° Likely increase in frequency of heavy precipitation events or increase in proportion of total rainfall from heavy falls over many areas of the globe, in particular in the high latitudes and tropical regions, and in winter in the northern mid-latitudes.
· ° Medium confidence in projected increase in duration and intensity of droughts in some regions of the world, including southern Europe and the Mediterranean region, central Europe, central North America, Central America and Mexico, northeast Brazil, and southern Africa.
Medium confidence is an attempt to convey a degree of certainty, and represents the middle of a five-point scale. Likely is defined as a 66-100% probability. Both are essentially personal judgements. Overall, despite all the undoubted hard work which went into producing the report, this tells us rather little. The underlying message is that, based on the particular assumptions made (in particular, that climate changes are dominated by the effect of additional atmospheric CO2, magnified by positive feedback mechanisms), droughts, floods and heat waves may become more frequent.
The call is for more to be spent on adaptation, which is surely what should be done in any case: vulnerability to droughts or floods needs to be addressed whether or not their frequency changes. There is, for example, a steady, small annual increase in sea level – no equilibrium has yet been reached after the last Ice Age – and flood defences have to be renewed from time to time. Assuring an adequate supply of water to, for example, many parts of sub-Saharan Africa plagued by cycles of drought is a problem which demands a solution whatever other changes may occur. The IPCC message in this case is a prudent one, albeit based on the recurring narrative of anthropogenic global warming.
But others are putting out far more extreme messages. In the UK, we have a Cabinet minister talking of the risk of conflict: Davey voices fears of looming ‘climate war’ risk. He identifies food, water and energy security as issues which could spark internal unrest; these can certainly be causes of tension and protest, but this speech (at a Foreign Office event) does seem like scaremongering in the cause of climate change policy. The recent history of wars suggests that ethnic, ideological or religious differences or disputed ownership of natural resources such as oil are the major underlying causes.
Such a position from a government minister is regrettable, but far more egregious are the views of James Hansen, currently head of NASA’s Goddard Institute of Space Studies. He has this week been awarded the prestigious Edinburgh Medal, ‘a prestigious award given each year to men and women of science and technology whose professional achievements are judged to have made a significant contribution to the understanding and well-being of humanity.’ For the sponsors of the medal (the Scottish Environment Protection Agency and Edinburgh City Council), he is clearly something of a hero.
Hansen has been in the forefront of promoting the supposed dangers of global warming since very publicly testifying on the issue to the US Congress in the 1980s. He sees this as a moral issue, which has to be tackled by the current generation for the benefit of our grandchildren. During his trip to the UK, he has given a number of interviews where he makes his opinions clear. For example, in the Guardian, we read Nasa scientist: climate change is a moral issue on a par with slavery.
And this is not the first time he has spoken so provocatively. In an article for the Observer in 2009 voicing opposition to the UK’s government's then likely approval of a new coal-fired power station at Kingsnorth (Coal-fired power stations are death factories. Close them), he said ‘The trains carrying coal to power plants are death trains. Coal-fired power plants are factories of death.’ In the same article, we wrote ‘Clearly, if we burn all fossil fuels, we will destroy the planet we know. Carbon dioxide would increase to 500 ppm or more. We would set the planet on a course to the ice-free state, with sea level 75 metres higher. Climatic disasters would occur continually.’
A year earlier, he had made equally controversial remarks to an audience of Democrats on Capitol Hill: ‘Special interests have blocked transition to our renewable energy future. Instead of moving heavily into renewable energies, fossil companies choose to spread doubt about global warming, as tobacco companies discredited the smoking-cancer link. Methods are sophisticated, including funding to help shape school textbook discussions of global warming. CEOs of fossil energy companies know what they are doing and are aware of long-term consequences of continued business as usual. In my opinion, these CEOs should be tried for high crimes against humanity and nature.’ (Are Big Oil and Big Coal Climate Criminals?)
Now Dr Hansen is doubtless a highly committed man who strongly believes in his message. But such extreme views, particularly from someone with a prestigious public appointment, are surely not helpful. By promoting the most alarming messages, he hopes to shock people into action, but will only serve to alienate the majority. His latest proposal is for an immediate 6% year-on-year reduction in greenhouse gas emissions, brought about by an escalating global tax on carbon.
His view that a carbon tax would be a simpler and more effective instrument than current failing trading schemes is undoubtedly true, but this idealistic proposal flies in the face of reality. Whatever the EU (or even the USA) committed to would be completely swamped by the growing economies of China and India, which are certainly not going to agree to a tax which slows their growth. Extremism has never been good. Fortunately, in this case, it is also unlikely to be popular.
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