Climate change progress up in air
Like so many of its predecessors, the Durban conference on climate change ended with observers wondering what if anything had been achieved, and a sharp difference between the optimists and the pessimists.
The South African chairwoman, Maite Nkoama-Mashabame, led the optimists. "We have made history," she declared. "We have agreed a plan to save the planet for our children and grandchildren."
Everybody would like to think that Durban has placed the planet on the road to salvation, but in the real world of rising seas and freakish weather the evidence was thin enough.
The conference agreed that a new climate change treaty should be decided by 2015 and would come into operation by 2020. Earlier, the three top polluters -- the United States, China and India -- had objected to these modest ambitions.
The conference also agreed to set up a fund to help poor countries to cope with the effects of global warming.
Although the major polluters came on board, effective action remained in doubt. The proposed treaty itself got a lukewarm reception, with the United Nations climate chief, Christina Figueres, calling the wording "ambiguous".
However, the central problem is not the future behaviour of the three giants but whether the global warming process has already gone too far to reverse. The scientific evidence, though fiercely questioned by "climate change deniers", is unequivocal.
Global warming has taken place and will continue to accelerate in the absence of determined action. We really do have a planet to save.