Professor John Sweeney:

I will begin by noting how important this Bill is and the need for effective action to tackle climate change. It is now quite clear that the world is warming at a faster rate than anticipated, by about 1oC, while the latest data show the landmass of Europe has warmed by between 1.7oC and 1.9oC. We are getting close to the point where it will become very difficult to comply with our Paris obligations unless we take really radical reductions in emissions.

Sometimes we think of climate change as a thing that is happening outside Ireland, but we know that Ireland is now 0.5oC warmer than it was in the 1960-1990 period. It is wetter and we are seeing quite a lot of extremes of weather and climate. I do not need to tell the committee of some of the consequences of flooding, for example, which were evident in Cork this morning. We saw the stormiest winter for 143 years, the wettest winter over most of Ireland since records began, and relatively unusual behaviour for Atlantic hurricanes, not going from east to west, but from west to east and maintaining hurricane status until getting very close to Ireland. It is not necessary to reiterate the problems of winter flooding. Climate science has advanced to the point where we can now attribute many extremes in terms of probability as a consequence of human action rather than something that might have happened naturally. The data show alarming increases in probability, such as for the French heatwave of 2019, of the order of ten to 100 times more probable. More recently, heatwaves in Eurasia this summer, where there were extreme temperatures right at the northern tip of Siberia, were about a thousand times more likely as a consequence of human action. It is important that this Bill tackles effective reductions.

I will make some recommendations on the Bill. As many members will know, I was the rapporteur on the 2015 Bill. I have watched with some dismay the language that was used there and which was subsequently proven ineffective being repeated in the amended version here. The first thing that must be tackled is to remove some of those "have regard tos" and "mays" and make the Bill something that achieves its purpose rather than something that is more designed to be defensive.

The State should achieve that. It is interesting to note that this morning the Northern Ireland Assembly received submission of a climate Bill which sets a target for decarbonisation of 2045. Dr. Jackson may go into that in more detail. We should not tie our policy completely to 2050. We should have the option of achieving that target earlier, as may happen at European level anyway.

It is important to have interim targets. I do not subscribe to the belief that they are not needed. Many Bills include interim targets. For example, the State is subject to interim targets for its existing 2020 obligations on an annual basis and has been exceeding those targets since 2017. The Bill should have a glide path with annual figures to indicate whether we are on the right path or trajectory. If we are not, then corrective action needs to be taken. It is very important to have a provision similar to that in the equivalent legislation in Scotland, in which annual values are provided. Interestingly, the Scottish environment minister was criticised because the 2018 reduction of 50% on its 1990 targets did not reflect the 54% which the annual value specified. It is a discipline which should be stressed.

On carbon budgets, there is a great deal of loose language. We must make carbon budgets consistent rather than having regard to the matters in section 3 (a) to (d) of the Bill. It is surprising that section 3, for example, does not mention Article 4 of the Paris Agreement. The long list from (a) to (y), which one might refer to as alphabet soup, does not refer to the Intergovernmental Panel on Climate Change, IPCC. If one wishes to have a Bill that is scientifically rigorous, the IPCC should be mentioned. I have an issue with the reference to "having regard to Government policy". Government policy is likely to fluctuate through the years. It is not clear to what the policy relates and whether it relates solely to climate or also to other considerations. That should be clarified. One can say with certainty that if it was solely relating to the programme for Government, we know the carbon budget for the next ten years will be approximately 429 million tonnes of CO2.. If that was the only criterion today, the issue then would be how to offload and segregate that into the two five-year periods. That will be a crucial issue in the coming months as we begin to decide that carbon budget. It may be that Government policy does not take into account what Ireland's fair share of the remaining carbon budget would be. There are other considerations. The more of this loose language there is in the Bill, the less likely one is to achieve the end goal.

I refer to carbon leakage. I do not know where that came from but it seems very unwise to include carbon leakage because it cuts both ways in terms of its legal definition. Some countries have ignored the environmental burden of production and exported their products to Ireland or are deemed to wish to so do. There are other countries that have stricter carbon emission reduction requirements than does Ireland. That may be the case, for example, in a situation where products being exported from Ireland will be deemed to be leakage from Ireland. I am thinking in particular of countries such as the Netherlands, where very strict reductions in emissions and its dairy herd are now being considered and production companies are seeking to establish new enterprises in countries such as Ireland. We must look very closely at that particular leakage phrase. I do not think it should be included in the Bill.

The issue of biogenic methane is a very complex one on which I may have to revert to the committee because it is not something that can be explained simply. The traditional and established way of measuring methane reflects its greater potency as a greenhouse gas. For example, in 20 years it will produce 86 times as much warming as one tonne of CO2. The bottom line is that there are slight differences between CO2 and methane in terms of their longevity in the atmosphere. The half life of methane is approximately ten years. It is still present in the atmosphere after that and much of it converts to CO2 thereafter. It is important to realise that the traditional way of measuring it, that is, the 100-year global warming potential, underestimates the potency of methane in shorter time periods. As a result, alternative methods of recognising those different lifetimes in the atmosphere, such as GWP*, have been suggested. It is important to emphasise that no matter what method one uses, it becomes clear that any increase in methane emissions will, for Ireland at least, very badly compromise our ability to comply with the Paris Agreement. In contrast, any significant and sustained reduction in methane will have a greater impact in helping us achieve our Paris Agreement targets than a comparable reduction in CO2. Methane is a critical gas which must be reduced. In the case of Ireland, its contribution to warming over the past few decades relative to that of CO2 has been enormous. All of this must be taken into account in the context that whatever way we wish to measure methane, the reporting requirement is simply established at United Nations Framework Convention on Climate Change, UNFCCC, level according to IPCC methodology, and that is the 100-year global warming potential criteria. When it comes to Ireland reporting, that is the only criteria that applies. Unless we can change the minds of 197 countries, that is the only way in which our greenhouse gas emissions will be reported in the years to come. Although it is open to policy makers to measure separate gases such as SF6 or methane and to have separate quantification of them, it is not open to them to start changing the reporting requirements at present.

I refer to the paragraphs of section 6 dealing with overshoot and undershoot. The section relates to circumstances where the carbon budget is not exceeded and the Minister may, effectively, bank those credits. I do not think one should be rewarded for achieving such a target. One should not be rewarded by being entitled to pollute more heavily in the next five-year budget, but that is another issue.