Governments have agreed (in COP16 in Cancun) on a long-term goal to limit warming to less than 2°C above pre-industrial levels – taking urgent action to meet this goal, consistent with science and on the basis of equity. They also agreed to consider strengthening this goal to limit warming to 1.5°C in light of recent science, which is what they are currently doing under the 2013-2015 review.

However, what countries haven’t so far done is to translate this long-term goal into the actual emissions phase out it requires. Taking this obvious next step in the Paris Agreement will help short term ambition and create a scientific backbone for future commitments and avoid a purely “bottom up” regime taking root.

Maximum 2°C warming translates into a need to urgently peak and rapidly decline global greenhouse gas (GHG) emissions towards zero. Specifically, carbon dioxide (CO2) emissions must be phased out to zero decades faster than all GHG emissions, as it is the cumulative emissions of CO2 that largely determine global mean surface warming.

The IPCC AR5 translates the 2°C maximum warming target into a carbon budget of maximum 1000 billion tons (Gt) of CO2 that can be emitted after 2012. Since early 2012, we have already used up 100 Gt of this budget. If CO2 emissions now peaked by 2020 and declined linearly thereafter, CO2 emissions would have to reach zero by around 2050.

Keeping warming to maximum 2°C requires carbon emissions to be phased out to zero by mid century (i.e. full decarbonisation). The Paris Agreement must acknowledge this fact.

Momentum is growing

Civil Society momentum for a long-term goal expressed as emissions phase out has grown rapidly over the last 18 months. Momentum at leader and negotiator level is gathering but is often patchy and inconsistently expressed. In Lima a goal of zero carbon by 2050 was included in the ‘elements paper’ – the list of all the possible building blocks to be used to construct the 2015 agreement. In Geneva this paper is to be turned into a proper negotiation text. On route to COP21 we need to:

  • Retain the inclusion of the carbon emissions phase out by 2050 goal in the draft treaty
  • Support it with language that signals fossil fuel phase out and renewable energy phase in
  • Build the army of allies that will fight for it in Paris and beyond.

What happened in Lima?

Off the back of the UN Climate Summit in New York momentum for the long-term goal was high. Thousands had marched on the streets calling for a 100% clean future and leaders from across the world had spoken up for a phase out of emissions.

In Lima civil society consistently pushed for the long-term goal – side events, lobbying, statements, actions and articles. And the high level platform for Climate Action hosted by the Peruvian presidency saw the World Bank, NCE, French, business, pension funds all rallying around a long-term goal of emissions phase out. Nearly 90 countries in one form or other supported the idea of such a long term goal.

This energy landed in Lima through the inclusion of various references to a long-term goal expressed as global emissions reductions in the elements paper – found in Section A (Preamble), Section C (General /Objective) and options in Section D (.Mitigation). One of them includes the kind of ambition civil society is looking for:

”carbon neutrality / net zero emissions by 2050, or full decarbonization by 2050”

However, this still requires further work to be as clear a message we want it to be to encourage fossil fuel divestment. After all, zero carbon implies zero fossil fuel emissions.

What might happen in Geneva?

Geneva is intended to deliver the draft text for negotiation at June and in Paris. There is no possibility that the Geneva session will itself secure the inclusion of a phase-out goal in the Paris agreement. However it is a key moment for building momentum with civil society and parties to increase the likelihood of securing it in Paris. It is thus crucial that the long-term goal options – and in particular the one referring specifically to the 2050 timeline – are not lost or downgraded in the text in the streamlining process that will take place in Geneva.

Which emissions pathway can keep us below 2C?

In end we have to get to zero emissions to cap warming at any temperature. CO2 emissions will have to be brought to zero decades faster than all GHG emissions. When considering the likelihood of a long-term goal option fulfilling the 2C obligation there are two key factors to keep your eye on greenhouse gas type and timeframe.

The below is a simplistic take on the latest IPCC scenarios (with some help from Ecofys and Carbon Action Tracker). If we don’t get to zero fast enough then negative emissions will be necessary – i.e. active removal of CO2 from the atmosphere with extensive afforestation or reforestation, carbon dioxide storage in combination with direct-air-capture, or by schemes that combine bioenergy use with carbon capture and storage, all of which are highly speculative at this stage and come with many uncertainties and real-world limitations.

For a likely (66%) chance of staying within 2C of warming:

  • CO2, net zero by 2055 – 2070, assuming net negative emissions follow thereafter. Less or no net negative emissions would require zero CO2 to be reached earlier.
  • All GHG, net zero, 2100

For a high (85%) chance of staying within 2C of warming:

  • Fossil fuel combustion & industry, net zero, 2055 – negative thereafter
  • All GHG, net zero, 2070 –negative thereafter

All the above options can get us to 2C but they differ on likelihood of delivery in a scientific (as above) and cultural (more or less agency for implementation) sense.

Can an emissions phase out be fair?

There is no fair scenario in a world that warms beyond 1.5/2C. People all over the world will be exposed, the vulnerable most of all. As ODI explains ‘poverty eradication will be difficult, if not impossible, if climate change is not tackled.’

But, is it fair to stop developing countries emitting? As the Mary Robinson Foundation-Climate Justice puts it, ‘enabling developing countries to continue investing in fossil fuel infrastructure would severely impede their development pathways in the long term… It is access to energy, not emissions, that is central to development.’

But, is it fair for them to take all the extra cost? The Mary Robinson Foundation-Climate Justice once again, ‘The only feasible way to achieve this is through the provision of support, both financial and technological, from those countries with greatest capacity. Only with this support will the phase out be achieved on a timescale which avoids dangerous climate change.’

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