Climate target ‘overshoot’ raises risk of legal actions and massive financial penalties

Q&A: Carbon budgets, EPA projections and their implications explained

The environmental group An Taisce has released analysis by climate experts Prof John Sweeney of Maynooth University and Prof Barry McMullin of DCU highlighting “a rapidly widening gap between Irish climate ambition and Irish climate action” because of an overshoot in the legally-binding 2021-2025 carbon budget adopted by the Oireachtas. Here is the issue explained:

What is a carbon budget?

A carbon budget represents the total amount of greenhouse gas emissions that may be emitted in the State during a five-year period, measured in millions of tonnes of carbon dioxide equivalent (Mt CO2 eq). It is calculated on an economy-wide basis.

The Climate Change Advisory Council (CCAC) proposed three five-year economy-wide carbon budgets up to 2035, to assist in achieving Ireland’s national climate objectives and EU targets agreed. These were adopted by the Oireachtas and, critically, they are legally binding.


All emissions and all relevant sectors are included in budgets, which are best described as ceilings on the amount of carbon that can be expended. They are an indicator of progress in decarbonising the economy – or not.

So for 2021-2025 the limit is 295 Mt CO2 eq requiring an average cut of 4.8 per cent annually. For 2026-2030 it is 200 Mt CO2 eq, an average cut of 8.3 per cent.

Approaching the midpoint of the first carbon budget, the CCAC said timelines for delivery of core measures within the Government’s climate plan were not progressing fast enough, ie emissions were too high.

Where does the EPA come in?

The EPA (Environmental Protection Agency) monitors emissions on behalf of the EU and regularly updates its projections for coming years on likely scenarios. The most recent update was last week.

It shows Ireland will definitely exceed its carbon budget to 2025 and is set to overshoot again for the period to 2030. As a consequence we are unlikely to comply with legal targets to halve our overall emissions by decade end with a 2018 baseline. Overshoots are projected by large margins.

The EPA provided emissions projection scenarios – called WEM and WAM – based on data for existing and projected additional Government policies. These projected emission pathways over time are then compared them with the legally-binding carbon budgets approved by the Oireachtas. It found the 2026-2030 budget is exceeded by 125 MtCO2eq for WEM and 80 MtCO2eq for WAM. None of this is disputed.

Where does the issue arise about its latest projections?

An Taisce, backed by analysis from climate specialists Profs Sweeney and McMullin, highlights the consequences of the carbon budget “overshoot” – ie sectors exceeding their ceilings – up to end of 2025.

They state the 2021 Climate Act “is very clear in its requirement that any overshoot of the first five-year budget must be carried forward to reduce the following five-year budget for 2026–2030 and this critical analysis, which is essential for decision-makers, is missing from the EPA report”.

In short, their analysis factoring in the overshoot concludes we are in a much worse state along the decarbonisation pathway, so much so it suggests the Government needs to intervene with “emergency course correction measures” across the economy to reset trajectories and in particular to avoid the huge implications for future governments that are likely to be placed in an even worse bind.

Even if meeting carbon budgets is not achieved in a particular period, Ireland’s commitment to the Paris Agreement means radical policies and measures to reduce use of fossil fuels and nitrogen fertiliser, and to limit timber harvest rates and peat extraction, “must still spell out the deepest possible emission reduction pathways for each sector”, An Taisce says.

The EPA has not commented on the overshoot implications, while the Department of the Environment, Climate and Communications acknowledged that where a carbon budget is exceeded “corrective or additional measures shall be introduced to ensure targets are met” in the next budget.

What are the implications of the sting in the tail from the latest EPA projections?

Correcting the carbon budget overshoot currently projected by the EPA may now require limiting emissions-intensive activity in sectors such as private transport, data centres, intensive agriculture and aviation, Sweeney and McMullin conclude. “Robust, effective, interventions will continue to be required at least until our economy and society can be properly redirected onto a genuinely sustainable trajectory.”

Clearly there should be less talk about targets and more attention on actions and removing obstacles to progress in forcing down emissions as quickly as possible. But missing carbon budgets “has profound legal and political implications”, they warn. There is a heightened risk of legal action facing future governments and massive financial penalties. And the failure of the current administration to respond adequately will severely limit future options for others.

Kevin O'Sullivan

Kevin O'Sullivan

Kevin O'Sullivan is Environment and Science Editor and former editor of The Irish Times