What the countries actually committed to in Paris - and how the agreement will affect us in Ireland
The parties to the Paris Agreement have committed to the following points - each one with implications for Ireland.
To hold the increase in the global average temperature to well below 2C above pre-industrial levels and pursue efforts to limit the temperature increase to 1.5C.
The planet has already warmed by 1C this century, and the science says that if it exceeds 2C, catastrophic climate change will arise and it will be near-impossible to adapt. The 1.5C goal is included at the request of the most vulnerable countries.
The only way to achieve this is to reduce emissions from industry, power generation, transport, our building stock and agriculture.
As part of the EU, Ireland has agreed ambitious targets, with a 40pc cut for 2030, ramping up to 80pc-95pc by 2050. That means sharp reductions, with details on how much from each sector to be decided in EU negotiations to be held next year.
To aim to reach global peaking of greenhouse gas emissions (GGE) as soon as possible, and balance emissions in the second half of this century.
The lack of definition and targets is considered a disappointment, but the deal effectively says that from 2050, all parties can only produce emissions if they can be compensated by carbon sinks, such as forests or bogs, which absorb GGEs.
The agreement also says that parties should take action to conserve and enhance these sinks and reservoirs of greenhouse gases - that means an end to widespread turf-cutting on a commercial basis and for power generation, as well as a need to plant trees.
Developed country parties are to provide financial resources to assist developing countries.
This is all about money, with $100bn (€91bn) to be given every year to vulnerable nations to help them adapt to climate change.
The funding must be from the public purse, and should be increased over time.
Ireland has committed just €2m for 2016, a sum widely considered inadequate, but Environment Minister Alan Kelly said that he would announce further funding in the coming weeks. Observers point out that the average contribution per head of population at the moment stands at around $20 - this means our contribution would have to increase to around €90m to be on a par.
To communicate intended nationally determined contributions (INDCs), and increase ambition over time.
Each party to the Paris Agreement must set out by how much it intends to reduce emissions (in targets called INDCs). These are expected to increase over time, to decarbonise the economy. Parties are not allowed to reduce their commitments.
As Ireland is part of the EU, we are part of the bloc's INDC commitments. As they increase, it will trickle down to member states, and agreement will have to be reached on the amounts to be cut from each sector of the economy.
Parties are to provide the information necessary for clarity, transparency and understanding.
This is so emissions cuts can be verified, and was a key sticking point. Countries like China aren't keen on being open to scrutiny, and therefore criticism, so the text says that verification will be "non-intrusive" and "respectful of national sovereignty".
This has no effect on Ireland. We already publish this information as part of our reporting requirements for Europe.