The UK government has published a book that collates evidence presented by scientists at a conference hosted by the UK Meteorological Office in February 2005 called Avoiding Dangerous Climate Change (Cambridge University Press). We've been aware that climate change is a problem for some time; we can now consider ourselves on alert that climate change is a real problem. Among its conclusions, the book states there is only a small chance of greenhouse gas emissions being kept below "dangerous" levels, and that rising concentrations of greenhouse gases may have more serious impacts than previously believed. In the book's foreword, UK Prime Minister Tony Blair writes that "it is now plain that the emission of greenhouse gases... is causing global warming at a rate that is unsustainable." The conference set two principal objectives: to ask what level of greenhouse gases in the atmosphere is too much, and what the options are for avoiding such a level; what did it come up with?Currently, the atmosphere contains about 380 parts per million (ppm) of carbon dioxide, the greenhouse gas linked closest to climate change and the principal concern of scientists, compared to levels before the industrial revolution of about 275ppm. The European Union adopted a previous target of preventing a rise in global average temperature of more than two degrees Celsius, which, according to the book, might be too high -- enough to trigger melting of the Greenland ice sheet. Above two degrees, says the report, the risks increase "very substantially", with "potentially large numbers of extinctions" and "major increases in hunger and water shortage risks... particularly in developing countries". The book concludes, therefore, that in order to have a good chance of achieving the EU's two-degree target, levels need to be stabilized below 450 ppm.
The UK government's chief scientific adviser, Sir David King, was less than cheery about the feasibility of such an accomplishment. "We're going to be at 400 ppm in 10 years' time, I predict that without any delight in saying it," he said. "But no country is going to turn off a power station which is providing much-desired energy for its population to tackle this problem - we have to accept that. To aim for 450 (ppm) would, I am afraid, seem unfeasible."
So what are the options for avoiding dangerous concentrations of greenhouse gases in the atmosphere? The book notes that the technological options to reduce emissions do exist. It concludes that the biggest obstacles to the take up of large-scale use of technologies like clean and renewable sources of energy lie in vested interests, cultural barriers to change and simple lack of awareness. ::Avoiding Dangerous Climate Change via ::BBC