The United Nations’ 20th annual climate talks, which finished on Sunday (Lima time), threatened to fall apart in the final 48 hours, but the negotiators managed to forge a final compromise. This left many parties and negotiating blocs not entirely satisfied, but that is the nature of compromise.

The climate negotiations, called the 20th Conference of the Parties (COP20), were held in Lima, Peru. COP20 was supposed to conclude on Friday but continued until around 1.30am on Sunday morning.

For those who measure success against the counterfactual of no agreement, the final decision at Lima, labelled the Lima Call for Climate Action, was therefore a diplomatic achievement.

Earlier versions of the draft decision had provided little solace to many developing countries. There was no mention of the principles of “common but differentiated responsibilities” and “respective capabilities”, a long-standing red line for the United States but crucial for most developing countries (especially those with minimal historical responsibility and weak capabilities).

And for the most vulnerable countries (especially the Philippines, which had suffered a third consecutive annual typhoon that coincided with climate negotiations), there was no mention of the Warsaw Mechanism for Loss and Damage, which had been established at the previous year’s annual UN climate summit. That was COP19 in Warsaw.

This mechanism is supposed to manage the unavoidable impacts of climate change for those countries that are the least responsible and the most likely to suffer the worst impacts of climate-related damage. The final text reintroduced differentiated responsibilities (albeit in the light of “different national circumstances”) and recalled the Warsaw Mechanism, albeit with no specific details.

However, for those who measure success in terms of distance from a collective optimum — in this case, holding climate change below 1.5 to 2 degrees Celsius of warming — the Lima COP decision was a major disappointment.

One major setback is that the parties avoided any commitment to raise pre-2020 ambition on mitigation (i.e. reining in rising global greenhouse gas emissions). This means that the parties are under no pressure to raise the non-binding mitigation pledges they made in the immediate aftermath of the Copenhagen climate conference in 2009.

This is despite the fact the negotiating roadmap for the planned 2015 agreement on climate, to be negotiated at the next COP in Paris, had called on the parties to raise their pre-2020 mitigation ambition in light of the Fifth Assessment Report of the Intergovernmental Panel on Climate Change, released over 2013-2014.

“… most parties stuck to their entrenched position as if oblivious to the growing groundswell of public concern about the increasing risks of dangerous climate change.”

Equally disappointing from Lima was the absence of any review mechanism of the parties’ mitigation targets included in their “intended national determined contributions” (INDCs) for the post-2020 period. INDCs are national targets on greenhouse emissions. The absence of a mechanism to review the targets was largely at the insistence of the Like-Minded Group of Developing Countries, which included China and India.

The review would have entailed an analysis of whether these targets, when aggregated, were sufficient to hold warming below the 2 degrees guardrail, and whether each contribution was fair — thus creating pressure for a further ramping-up of ambition.

Instead, parties are merely called upon to make their own case as to why they think their INDCs are “fair and ambitious, in light of its national circumstances, and how it contributes towards achieving the objective of the Convention”. The UN Framework Convention on Climate Change (UNFCCC), which runs these annual summits, will provide a synthesis report by November 1, 2015. There will be no formal peer review and little time for informal review before Paris.

Nonetheless, the final decision did require parties to provide the necessary information to enable others to judge the fairness and adequacy of INDCs (i.e. targets), plus a requirement that there must be a progression beyond previous commitments — in short, no backsliding. When Australia’s Abbott government finally reveals its INDCs around mid-2015, it will be interesting to see its defence of fairness and ambitiousness — two issues it has steadfastly ignored thus far.

While the parties achieved the $10 billion threshold for finance to help developing countries adapt to climate change and reduce emissions, there was no clear pathway agreed as to how the required $100 billion would be raised by 2020. This is absolutely crucial for poor countries, dependent on this assistance for their own decarbonisation and adaptation.

The parties also avoided any serious discussion of what form the 2015 Paris agreement would take. The options range from a legally binding Paris protocol to an “agreed outcome with legal force”, which might entail a mostly aspirational agreement but with a commitment by the parties to give domestic “legal force” to their INDCs.

More generally, most parties stuck to their entrenched position as if oblivious to the growing groundswell of public concern about the increasing risks of dangerous climate change. Looking ahead, it is clear that the draft negotiating text containing the key elements of the 2015 deal, which was worked over by the parties but left bristling with unresolved disagreement, will require a lot of hard work over the next 12 months to bridge entrenched differences and bring it into a shape that might win consensus in Paris.

*Read other blog posts from University of Melbourne academics who have been at Lima here.