Q&A: Copenhagen climate change conference 2009

The world is on the brink of an environmental calamity of Biblical proportions, scientists believe. So what can 11 days in Copenhagen do about it?

By By Julian KossoffPublished: 4:42PM GMT 19 Nov 2009

Hu Jintao and Barack Obama must attend the Copenhagen summit it is to be successful
What is the Copenhagen climate change summit?
From 7 December 2009, the leaders of the world's 180 countries -backed by a 20,000-strong army of officials, advisors, experts and journalists - will attend a United Nations meeting in Copenhagen to thrash out a new international deal to tackle climate change.

Whatever is agreed at Copenhagen will come into force on 1st January 2013, and supersede the last attempt to save the environment, the Kyoto protocol.
Who are the key players?
US President Barack Obama and President Hu Jintao of China must attend if there the chance of something significant being agreed.
Other important figures will be the representatives from the developing economies of India and China. It is feared that the newly industrialised nations are on course to repeat the mistake of over-reliance on fossil-fuel energy begun in Europe, North America and the former Soviet Union.
Gordon Brown was the first world leader to announce in September that he was ready to go to Copenhagen to help secure a deal.
Do summits work?
Kyoto in 1997 was considered a qualified success.
The Treaty signed there bound by law the world's 37 richest countries to cut their emissions by 5.2 per cent from 1990 levels by 2012.
America bailed out of the negotiations (and subsequently went on increasing emissions by 20 per cent) but as a group the target should be achieved, helped by the one-off bonus of the collpase of heavy industrial output in the former Soviet Union.
What are the main aims of the summit?
In the long term, wealthy countries are under pressure to agree to emission cuts of greenhouse gases of up to 80 per cent by 2050 (Britain has already signed up to this) and limit global climate change to 2C.
Copenhagen must bring the USA on board. Its 250-million strong population (less than 5 per cent of the world total) gorges itself on energy producing up to 30 per cent of all emissions.
Convincing developing nations they must not follow the West's profitable mistakes, which means billions of dollars and a fair share of the latest green technology.
Is doing nothing an option?
If we do nothing, scientists predict climate change will rise by 6C by the end of the century triggering a catastrophe including: extreme weather, sea level rise, water shortages, food shortages and the extinction of up to a third of known plant and animal species.
However, climate change sceptics dismiss the arguments of human interviention in climate change and argue that natural phenomenon, for example volcanoes erupting , are to blame for the increase in carbon dioxide since the industrial revolution.