There has been a lot of speculation about what any future climate agreement will look like. By 2015, the world's leaders are scheduled to come to a decision on what direction it will take.
Many developing countries are calling for a continuation of a stringent rules-based and legally binding protocol as the only way to motivate nations to commit to emissions reductions.
On the other hand, developed countries – and Australia in particular – are pushing for an agreement which allows countries to set their own targets and means for achieving them.
The contrast between the two positions symbolises the overarching debate over whether a 'top-down' or a 'bottom-up' approach to climate change mitigation should be adopted. While the former involves prescribing countries what they must do to alleviate climate change and forcing them to comply, the latter allows them flexibility to work it out altogether themselves.
Whatever the new agreement is, it needs to do three things: raise ambition, foster widespread participation and ensure compliance.
But Christiana Figueres, the UN's top climate change envoy, has said she foresees a compromise between the two approaches instead. She has also suggested that a dynamic hybrid of agreements, where countries can pick and choose from an assortment of prescribed commitment schemes is likely to be part of any solution. This 'house with many rooms' approach will allow nations to have some flexibility in choosing their commitments based on what their national circumstances permit them to take.
One solution would be to have a core agreement with several optional annex groupings among which countries can decide the best one for them to belong to.
For example, one of these annexes could potentially consist of rigorous Kyoto-style emissions targets for developed countries, while another could take the form of domestic policies parties commit to implement.
An agreement of this kind will have some perks.
By drawing enough of a middle ground between the polarised interests of all the parties, it would be successful at fostering widespread participation and compliance.
The hope is that over time, participation from a diverse range of nations will provide dynamic feedback and more scope for review, while also generating the trust and confidence across countries which is lacking at the moment.
However, the agreement will categorically fail to generate the level of ambition across countries in the short term needed to achieve the global goal of capping the global average temperature rise at two degrees Celsius by 2050.