Julian Hunt.jpg- Julian Hunt is visiting professor at Delft University and formerly director general of the UK meteorological office. Charles Kennel is distinguished professor of atmospheric science, emeritus and senior advisor to the sustainability solutions institute, UCSD. The opinions expressed are their own. -

The non-legally binding "deal" agreed at the U.N. Climate Change Conference in Copenhagen among the U.S., China, Brazil, South Africa and India, has brought to a conclusion what has proved an extraordinarily complex set of negotiations.

The outcome has been criticised on numerous grounds and, in U.S. President Barack Obama’s own words, “We have much further to go”.

In effect, the agreement may ultimately amount to no more than a long-term climate change dialogue between Washington and Beijing.  While global action to tackle emissions of carbon dioxide must remain a priority, the fact remains that we may be heading towards a future in which no long-term, comprehensive successor to the Kyoto regime is politically possible.

One of the chief flaws in the Copenhagen negotiations was the fact that the overly-ambitious political deals being discussed were not realistic, nor framed to inspire people to act and collaborate with each other across the world on both a local and regional level.  Going forwards, national governments will need to be more honest about future likely emissions and also of future temperature changes.  In this crucial debate, scientists must be free to state their estimates without political bias.