A number of conclusions can be drawn from the present analysis in relation to the use of fossil fuels and indeed of greenhouse gas emissions over the next century. With action on deforestation a budget for fossil fuels over the next century of around 225 GtC may enable long term warming to be limited to around 1oC.
The present findings are consistent with earlier work, taking into account both the improvements in scientific knowledge over the past decade and the changes in the international policy context.
The conclusion that there must be an ecological limit to burning fossil fuels is robust to a wide range of assumptions. Even if the climate is less sensitive to human interference than the current evidence suggests, or governments fail to take a precautionary approach to setting limits, a `carbon budget' is will still result which is less than current fossil fuel reserves. This has several implications:
* Coal use needs to be phased out as rapidly as possible. Only a small fraction of the economically recoverable reserves can ever be used. Coal has the highest carbon intensity of the conventional fossil fuels. Coal is subsidised in many parts of the world and these subsidies should be moved, where necessary, to renewable energy systems.
* There should be no further exploration and development of unconventional oil and gas reserves. Estimated economically recoverable volumes of gas and oil in this category are sufficient alone to breach the `carbon budget'. These resources should not be allowed onto the market as doing so will inevitably lead to cost reductions through production scale effects. This can only make it more difficult to phase out fossil fuels.
* There will need to be significant constraints placed on the technical development and exploration of known oil and gas reserves. Volumes in these reserves, particularly when taking into account the process of reserve appreciation following technical developments are sufficient already to breach the `carbon budget'.
The timing and location of these actions is important. All of these actions should be undertaken by industrialized countries first as they have the responsibility under the climate convention to do so. It is important that policy signals are sent sooner rather than later. The recent move by Denmark to announce the phase out of the use of coal in that country must only be the beginning.
Greenpeace believes that ultimately CO2 has to be stabilized at or below current concentrations and that the maximum long term increase in temperature that policy makers should have in mind is 1oC above pre-industrial levels. Avoiding dangerous climate change would require cumulative fossil carbon emissions over the next century to be less than 300 GtC and as low as 145 GtC if no action is taken on deforestation. The central estimate of an allowed fossil fuel budget that would meet the global ecological objectives set by Greenpeace is 225 GtC.
Delaying the beginning of the phase out of fossil fuels will just reduce the amount available for later generations. With the majority of current emissions being in developed countries this could also mean that the overall budget for developing countries would be smaller.
The most important short term step in beginning the phase out of fossil fuels is the adoption by industrialized countries of a legally binding CO2 emission reduction target for the year 2005 at COP3 in Kyoto. At the same time national governments should be taking steps to:
* Begin the phase out of coal power stations and coal mining.
* Adopt policies to reduce emissions of CO2 and other greenhouse gases
* Stop plans to allow the expansion of exploration for oil and gas reserves
* Stop all development of unconventional oil and gas reserves.
The ultimate phase out of fossil fuels is technically and economically feasible. The `Fossil Free Energy Scenario' (FFES)[126] prepared by the Stockholm Environment Institute for Greenpeace in 1993 demonstrates that it is economically and technically feasible to phase out fossil fuels through major improvements in energy efficiency, especially in the transport, buildings and electricity sectors and rapidly introducing renewables such as wind, solar and biomass[127]. Based on a wide range of studies around the world and an economic analysis, the study predicts that a phase-out of fossil fuels can be achieved at a cost equal to or less than "business-as-usual" scenarios.
[126] Lazarus op.cit. Apart from the climate constraint placed on the energy system the scenarios assumes the phase-out of nuclear power by 2010. Fossil fuels are eliminated between 2075 and 2100.
[127] The assumptions for the study were deliberately taken from conventional sources used in other global energy scenario studies, and include United Nations population forecasts of 11.3 billion people in the year 2100, and huge projected increases in global GDP (up by a factor of 14 over the study period) based on IPCC and World Bank studies. They also include assumptions that countries from the South will follow the Northern model of economic development (resource-intensive industrialisation, followed by a move towards the Services sector).