According to climate models, we could be in for a rough time later this century. The Royal Society has published a report this week detailing what to expect and how societies can deal with it (Resilience to extreme weather). This is reported by the BBC as Risk from extreme weather set to rise. The working group was chaired by Prof Georgina Mace, Professor of Biodiversity and Ecosystems at University College London, and included fifteen other eminent scientists, and it is she who has commented to the BBC’s Roger Harrabin.
In her words, “This problem is not just about to come… it’s here already." But the study offers a somewhat more nuanced view than the headlines would suggest. As Prof Mace also said “People are increasingly living in the wrong places, and it's likely that extreme events will be more common…For most hazards, population increase contributes at least as much as climate change - sometimes more. We are making ourselves more vulnerable whilst making the climate more extreme.”
The main problem is that more people may be at risk because continuing urbanisation, particularly the growth of established cities on coasts or rivers, increases the number who may suffer from storms and flooding. Another problem is the impact of heatwaves, exacerbated by the urban heat island effect, and made even more serious by the rising number of elderly people, who are often least able to deal with unusually high temperatures.
On the other hand, we can see a positive impact of higher temperatures in the form of mild winters in another story: Lowest ever winter deaths recorded. During the 2013/14 winter, there were 11.6% excess deaths in England and Wales compared with the rest of the year. This is 18,200 additional deaths, with 14,000 of them among over-75s, and compares with averages of around 60,000 in the 1950s, when the population was both smaller and younger.
Better healthcare has some part to play, but the biggest factor is undoubtedly temperature. Keeping warm reduces the chance of dying in winter. The relatively-mild UK actually has a higher rate of excess winter deaths than colder northern European neighbours, probably because people in these countries live in warmer, better-insulated houses. It is difficult to make a direct comparison, but an observation to note is that about 3,000 people were believed to have died in the French 2012 heatwave, many fewer than in even a mild winter.
The greatest risks, however, are in developing countries. According to the report, only 11% of the total number of people exposed to the hazards of extreme weather live in poor countries, but that is where over half of disaster deaths occur.
Overall, many of these deaths could be avoided by taking relatively simple precautions to protect populations at risk, but many poor countries simply cannot afford these or else have weak governments with little capacity to improve infrastructure. In simple terms, facilitating economic growth and good governance is a necessary first step towards increased resilience. Having an affordable supply of clean energy is another one, because this is what has enabled developed countries to install the heating and cooling systems which make life comfortable (and healthy) whatever the season.
But this is at odds with the demand for global emissions of carbon dioxide to be cut to limit the extent and impact of global warming later this century. Providing energy reliably to everyone means relying for the most part on fossil fuels. Unless, that is, countries are prepared to invest in a major expansion of nuclear energy. Unfortunately, there is little sign of that happening right now.
An alternative which has also had some publicity this week is geo-engineering; deliberating countering global warming by taking other action such as injecting sulphate aerosols into the upper atmosphere, to provide the sort of cooling influence observed after massive volcanic eruptions. But such interventions are highly controversial because of the risk of unintended consequences. Three studies have been published recently, and their authors have spoken to the BBC’s David Shukman (Geo-engineering: Climate fixes ‘could harm billions’).
Dr Matt Wilson of Bristol University is quoted in the piece: "We don't like the idea but we're more convinced than ever that we have to research it. Personally I find this stuff terrifying but we have to compare it to doing nothing, to business-as-usual leading us to a world with a 4C rise." One of the biggest concerns is the potential effect on rainfall patterns. A particular type of geo-engineering could be beneficial for one region but disastrous for another. For an analysis of the implications of this, read David Shukman again: How could man intervene to change the climate?
There are clearly no easy answers, but it is right that people are beginning to consider options other than the present focus on radical cuts in emissions. Assuming the climate models give a realistic picture of a late 21st Century world (and, to be honest, it’s difficult to put much faith in them based on the increasing gap between projection and evidence) then any significant mitigation in coming decades relies on two key things. The first is a strong and binding international agreement to limit and reduce emissions, with all signatories meeting their obligations. Without wishing to seem unduly negative, the chances of this happening at the Paris climate summit in a year’s time seem slim.
The second is one we don’t hear enough about: carbon capture and storage. Despite large amounts of public money being made available for demonstration projects, no-one has yet shown that this is feasible on a large enough scale to make any difference. Without that, even the most stringent feasible emissions reduction plan would fail to limit the projected average temperature rise to 2°C. Global emissions cannot possibly peak until China’s do, and that goal will not occur until at least 2030, by which time annual emissions will be much higher than today.
Research on all options – improved nuclear, new energy sources, energy storage, carbon capture and geo-engineering – should continue because we don’t know where breakthroughs will come. But, if CO2-driven global warming is as real as we are told, the world cannot continue paying lip service to emissions reduction policies which don’t deliver. Hard choices will have to be made at some stage.
Martin Livermore
The Scientific Alliance
St John’s Innovation Centre
Cowley Road
Cambridge CB4 0WS
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