The scientific report, compiled by Sir Nicholas Stern for the UK government, says there is only a small chance of greenhouse gas emission, particularly carbon dioxide, being kept below “dangerous” levels. The world has to act now or face devastating economic consequences.
What will happen?
If no action is taken on emissions there is a more than a 75% chance of global temperatures rising between two and three degrees Celsius over the next 50 years and a 50% chance of average global temperatures rising by five degrees Celsius. The Greenland ice sheet is likely to melt, leading sea levels to rise by 7 metres (23 feet) over 1,000 years. But much of the devastation will take place in the next few decades. The poorest countries will be most vulnerable as floods increase, crop yields decline (particularly in Africa) and rising sea levels leave millions of people permanently displaced. Up to 40% of species could face extinction and there will be more extreme weather.
The report, Avoiding Dangerous Climate Change, collates evidence presented by scientists at a conference hosted by the UK Meteorological Office in February 2005.
The economic impact
The economic impact will be considerable. Extreme weather could reduce global gross domestic product (GDP) by up to 1% and a two or three degree Celsius rise could result in up to 10% of global output being lost, and even more for the poorest countries. In a worst case scenario global consumption per head could fall by one fifth. To stabilise at manageable levels, emissions would need to stop rising in the next 20 years and fall between 1% and 3% after that. This would cost 1% of GDP.
Targets
Although the European Union has adopted a target of preventing a rise in global rising temperatures of more than two degrees Celsius that may be too high. The report says that two degrees might be enough to trigger melting of the Greenland ice sheet. Above two degrees may increase risks “very substantially” with “potentially large numbers of extinctions” and major increases in hunger and water shortage risks “particularly in developing countries”.
The report asked scientists to calculate which greenhouse gas concentrations in the atmosphere would be enough to cause the “dangerous” temperature increases. Currently the atmosphere contains about 380 parts per million (ppm) of carbon dioxide and to reach the EU’s two degree target, levels need to be stabilised at 450ppm or below. Worryingly and despite the fact that the two degree target in itself is too high, the UK government’s chief scientific advisor, Sir David King, said the 450ppm seems “unfeasible”. He expects the target to reach 400ppm in the next 10 years.
“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”, Sir King comments.
What can we do?
The options for change include: reduce consumer demand for heavily polluting goods and services, make global energy supply more efficient, act on non-energy emissions (preventing deforestation for example) promote cleaner energy and transport technology, with non-fossil fuels accounting for 60% of energy output by 2050.
The Stern Report says there are technological options to reduce emissions – for example renewable sources of energy and “clean coal”, but that the biggest obstacle lies in vested interests, cultural barriers to change and simple lack of awareness.
What is the government’s response?
Tony Blair writes in the forward to the report that “it is now plain that the emission of greenhouse gases… is causing global warming at a rate that is unsustainable”.
The government has outlined a number of measures to cut the emission of greenhouse gases and halt global warming. These include:
- create a global market for carbon pricing
- extend the European Emissions Trading Scheme (EETS) globally to bring in countries such as the US, India and China
- set new target for EETs to reduce carbon emissions by 30% by 2020 and 60% by 2050
- pass a bill to enshrine carbon reduction targets and create a new independent body to monitor progress
- create a new commission to spearhead British company investment in green technology with the aim of creating 100,000 new jobs
- take advice on the issue from the former US vice-president Al Gore
- work with the World Bank and other financial institutions to create a $20 billion fund to help poor countries with climate change
- work with Brazil, Papua New Guinea and Costa Rica to promote sustainable forestry and prevent deforestation
If you wish to read the entire report goes to www.hm-treasury.gov.uk
