By Richard Black
Environment Correspondent, BBC News website
November 2005: the Kyoto Protocol has been in force for six years, emissions of greenhouse gases are falling fast, and all governments accept the message of urgency coming from mainstream climate science.
Flying pig: Same chances as a meaningful deal in Montreal?
With the Kyoto targets already achieved, the Montreal summit will focus on the next round of commitments for developed and developing countries alike.
Richer states are preparing to pledge cuts of 30% by 2020, as a step towards their declared aim of 90% reductions by 2050; while developing nations have agreed an initial target of 5%.
There is consensus across the board that every citizen of the planet should be entitled, in the long term, to the same allowance for emitting greenhouse gases.
The only potential problem Montreal delegates may face is the number of flying pigs migrating north-eastwards from Lake Ontario.
Reverse through the looking glass
Well, that's how the meeting could be panning out - if we lived on a parallel Planet Earth.
Certainly, the picture painted above is more akin to the visions which climate specialists had in 1997, rather than today's uncomfortable morass.
In reality, of course, the protocol came into force only this year; and while many interested parties continue to insist on firm targets and timetables beyond 2012 - the period covered by Kyoto - there are now powerful forces pulling in the other direction.
What, then, can we expect from the Montreal talks? Will they be meaningful negotiations, or merely talks about talks about talks - cubic kilometres of hot air jumping through hoop after pointless hoop?
HOW ARE THE TALKS CONSTRUCTED?
This is the 11th round since it all began at the Rio de Janeiro Earth Summit in 1992.
The Rio de Janeiro Earth Summit: Where it all began
But, for the first time, the two-week-long talk-in consists of two meetings in one.
Some of the discussions will concern the Kyoto Protocol; and countries which have put themselves outside the protocol, such as the United States and Australia, are permitted only to observe.
Other discussions pertain to the original UN Framework Convention on Climate Change (UNFCCC) and will include everyone.
After a fanfare of arrivals, the first week will consist largely of behind-the-scenes negotiations, with ministers arriving only for the final few days.
WHAT IS THE SCIENCE TELLING US?
Since the Kyoto Protocol was signed in 1997, the evidence for human-induced (anthropogenic) climate change has grown apace.
There is hardly a single scientifically qualified climate specialist on the face of the planet who believes the Earth's surface is not warming.
Uncertainties remain as to the likely extent and to the degree of human involvement.
But there is general agreement that whatever happens now politically, there will inevitably be a warming of between one and two degrees Celsius, with potentially serious consequences in some regions, principally in poorer parts of the world.
One of the burning questions of the moment is what constitutes dangerous climate change?
All countries present, even the Kyoto naysayers, have a duty under the Framework Convention to stabilise greenhouse gases at levels which do not cause "dangerous anthropogenic interference with the climate system".
But what "dangerous" means has not been defined, though there is a consensus growing around two figures:
- an average global temperature rise of more than two degrees Celsius
- a carbon dioxide concentration in the atmosphere of more than 400 ppm (parts per million)
At the current rate of rise, 400 ppm will be reached in 10-15 years; and, as noted above, concentrations of greenhouse gases may already be high enough to make a temperature rise of one-and-a-half degrees inevitable.
WHAT IS HAPPENING TO EMISSIONS NOW?
The more developed the country, the more reliable the data; the Kyoto Protocol requires Annex 1 nations (those which are required to make cuts) to provide in-depth annual reports.
Thirty-seven Annex 1 countries now remain inside the protocol.
Of these, about half are seeing their emissions rise, while the other half have seen a fall since 1990, the baseline for UN calculations.
Broadly, the ex-Soviet bloc countries are the ones where greenhouse gas production is going down - 39.6% between 1990 and 2003 - while it went up by 9.2% during the same period in the others.
Although the US and Australia have pulled out of the Kyoto process, their emissions have risen less than some nations which remain within the treaty.
The International Energy Agency calculates that rising energy demands will mean a global increase in industry-related emissions alone of 62% between now and 2030.
By contrast, accepting the figures of 400 ppm for CO2 and two degrees Celsius for temperature rise would suggest that emissions need to come down by something in the order of 62% between now and 2030.
WHAT ARE THE BIG PLAYERS BRINGING?
Much of the discussions will involve the minutiae of the Kyoto Protocol, though there are serious issues here.
One is the Clean Development Mechanism (CDM), a system set up to enable richer countries to meet their targets through investing in developing nations.
CLIMATE CHANGE: TIMELINE
1988 - IPCC formed to study climate change
1990 - first IPCC report concludes scientific basis for man-made greenhouse warming is sound and major impacts may occur
1992 - Earth Summit - nations pledge to prevent 'dangerous' climate change
1995 - second IPCC report hardens scientific case
1997 - Kyoto Protocol signed
2001 - IPCC third report - warming of up to six degrees Celsius by end of century
2001/2 - US and Australia withdraw from Kyoto Protocol
2005 - Protocol in force
2005 - Asia-Pacific Partnership announced
2005 - Montreal meeting - where now?
It does not appear to be working terribly well, and there are likely to be calls for more investment, resources and oversight.
What there should logically be, now that the Kyoto Protocol is in force, is discussion on further targets and timetables, something which is enshrined in the treaty's wording.
But of firm numbers, there has so far been almost no mention.
This may be because countries which are so far off meeting existing targets do not want to discuss new ones; while developing states know that if they push the west for tougher action, they may be pressed to adopt targets themselves.
In a news briefing the week before the Montreal discussions opened, President Bush's chief environmental advisor, James Connaughton, made clear the US would not support binding targets.
"We don't need them," he told reporters, pushing the case that "many of the more consequential initiatives [on cutting emissions] have occurred outside of a treaty process."
United States officials have pledged not to oppose targets if that is what other nations want, but some observers greet that with scepticism.
In July, the US, together with five other coal-intensive countries, announced the formation of the Asia-Pacific Partnership on Clean Development and Climate.
The stated aim is to reduce emissions though voluntary partnerships and technology while safeguarding economic growth.
Although their agreement acknowledges the primacy of the UN process, it provides a rival model of emissions reduction which appears highly seductive.
Though the Bush administration has accepted since 2001 that the climate is changing and humans are partially responsible, Mr Connaughton also denied there was any consensus on what constitutes dangerous climate change.
"We remain committed to stabilisation," he said, though at a level which is "not defined".
The European Union, though, has adopted two degrees Celsius as a threshold which should not be crossed.
But precisely what cards Europe will play in Montreal is a different question.
The delegation will be led by Britain, which currently holds the EU Presidency; and as my colleague Roger Harrabin discusses elsewhere on these pages, there have been signs of a recent movement by British leaders towards the US position.
"We are hoping that British ministers will stick formally to an approach based on industrialised countries having greenhouse gas targets based on the most recent science," said Tony Juniper, executive director of Friends of the Earth UK.
"That is something that is non-negotiable as far as the EU core position is concerned."
WHAT WILL DEVELOPING COUNTRIES BE PRESSING FOR?
Traditionally, the loudest developing country voices have been those arguing that their economies should be allowed to develop without restrictions on greenhouse gas emissions - and, by implication, on economic growth.
But there is also growing alarm about the potential impacts of climate change.
Rajendra Pachauri, who chairs the Intergovernmental Panel on Climate Change (IPCC), the body charged with providing scientific evidence to feed into UN negotiations, believes that economic concerns will win out.
Coal remains a vital but controversial energy source
"There is a lot of concern about the impact of climate change," he told the BBC News website.
"But developing countries make repeated reference to the clause in the Framework Convention which talks of 'common but differentiated responsibilities'.
"This accepts that developed countries must take the first steps, and the fact remains that in per capita terms, emission levels from countries like India and China are much lower than in the developed world; so I think developing countries will remain against binding targets for now."
WHAT ARE THE LIKELY OUTCOMES?
On the really big questions - whether there should be a binding treaty post-Kyoto, and whether developing nations should be subject to any targets at all - little progress is likely.
Look for plenty of noise in the corridors and alleyways - lots of vocalising against the US and Australia, and pressure on the EU and Japan to stay firm - but few concrete signs.
Where meaningful progress is likely is on issues like the CDM, on helping developing countries to monitor emissions, perhaps also on expanding avenues for technology transfer.
Chances of the flying pigs materialising? Close to absolute zero.