KEY POINTS:
Even before the Kyoto Protocol comes into effect in the new year, the world will gather in Bali next month to see if it can muster the political will to begin negotiations on a successor treaty.
How daunting their task is, and how much New Zealand has at stake, is apparent from a book to be published this week, Towards a New Climate Treaty: Looking Beyond 2012, edited by Jonathan Boston of Victoria University of Wellington's Institute of Policy Studies.
One of the contributors is New Zealand's climate change ambassador, Adrian Macey.
In the 10 years since Kyoto was negotiated we have learned a lot more both about the climate and the technologies available for mitigating global warming, Dr Macey writes.
"Essentially emissions need to peak in the next 10 or 15 years, then decline to low levels."
The New Zealand delegation's guiding principles at Bali would be the need for environmental effectiveness and maintaining the competitiveness of the economy.
New Zealand's emissions profile is unusual in two respects: half of it comes from agriculture which is hard to reduce with current technology, and our electricity is already 70 per cent from renewable sources, limiting the scope of reductions there.
A successor to Kyoto will need to be deeper, broader and longer.
It needs to deliver deeper cuts to emissions, which are expected by 2012 to be 30 to 40 per cent higher than they were when Kyoto was negotiated, only marginally less than would have occurred under business as usual.
It needs to be broader in the sense of putting some obligations on the larger developing economies.
Kyoto's division of the world into developed and developing countries, with only the former undertaking obligations to reduce emissions, needs to be replaced with something more nuanced, Professor Boston argues, now that developing countries produce more than half of the world's emissions, and some "developing" countries like Singapore are richer than some "developed" ones, like New Zealand.
And the new agreement will need a longer life span than the five years of Kyoto's first commitment period, to give investors more certainty about the regime they have to work within.
Pamela Chasek, an expert on international environmental negotiations, reflects on some of the geopolitical challenges overhanging the Bali talks.
The Bush Administration rejected Kyoto and its mandatory cutbacks in 2001 on the grounds that they would hobble the US economy and did not apply to China and other industrialising countries.
Despite mounting domestic and international pressure it has held fast to that view.
But if the world has to wait until after George W. Bush leaves office in January 2009, there is unlikely to be enough time to negotiate and ratify a new agreement before Kyoto runs out, she argues.
A key issue for any new treaty will be deforestation.
It is estimated deforestation is responsible for 18 per cent of global emissions, more than the world's entire vehicle fleet.
And while the focus of a post-2012 agreement will be on how to "bend the curve" - get emissions to peak and start declining - there is expected to be an increased emphasis on adaptation or coping with the consequences of climate change.
