- The Intergovernmental Panel on Climate Change (IPCC) Working Group 1 (The Physical Science Basis) has given a broad, systematic summary of the scientific literature on climate change and has concluded that the anthropogenic emission of greenhouse gases has led to an increase in the surface temperature of the Earth.
- The relationship between climate forcing and the response to climate forcing is complex and can only be reliably identified for periods of several decades and for hemispheric and global domains. This is supported by both empirical and modelling studies. Trends of shorter periods are unreliable and masked by the chaotic behaviour of the climate system. However, based on detailed theoretical and modelling studies, IPCC concludes that the observed warming of the climate from around 1970 is in broad agreement with the increase of greenhouse gases and aerosols and consequently considers this to be the most probable main cause of the present global warming.
- IPCC has undertaken modelling studies to estimate the effect of anthropogenic greenhouse gases and aerosols on climate during the next 100 years based on different emission scenarios. These studies indicate a global surface warming at the end of the 21st century of 1.5-3.5 °C compared to present-day conditions. A large part of this warming is related to positive feedback from water vapour that increases rapidly with higher temperature.
- Regrettably, we are not yet in a position to determine with any precision what is going to happen.
- The EU is now sending a forceful and clear signal to other countries in the run-up to the climate meeting in Copenhagen. We are prepared to show the political leadership necessary to save the climate and reach an agreement in Copenhagen that will keep global warming to under two degrees Centigrade.
- Long-term targets for the EU of 80-95 per cent emissions reductions by 2050 compared with 1990 levels.
- Clarification of EU demands on industrialised countries and developing countries alike. Industrialised countries are to reduce their emissions by 25-40 per cent by 2020. The reductions of developing countries will be 15-30 per cent compared with a situation in which no measures had been taken.
I have commented the statement on climate change by the Academy on my blog, and would like answers to the following questions posed there:
- Has the Academy made an independent evaluation of the science presented by IPCC, and if so what is the result?
- If not, why does the Academy as a scientific academy make a statement only repeating what IPCC says?