Professor John Sweeney:

It is difficult to know where to start. There have been so many questions that it would occupy a full college course on the topic. I will do my best, however.

The build-up to the Paris conference was the key to its success. I attended the abortive 2009 Copenhagen conference but came away from it disillusioned, realising that it set us all back by seven years. To get back on track for where we hoped to be after Copenhagen, there was a sense in the world community that it could not happen again that way in Paris in 2015. Several matters conspired in getting the choreography right before Paris actually happened. The first was the effort by the US President, Barack Obama, to forge an agreement with China. That agreement was forged in the later stages of his presidency but it was one that took much of the sting out of any agreement that might be reached for the rest of the world.

The second factor was the efforts of the Secretary General, Ban Ki-Moon, who has worked tirelessly over the past few years to bring world leaders together in the build up to Paris to ensure that an agreement was reached. There were several summit meetings at the United Nations and he travelled throughout the world to meet on a one-to-one basis with many leaders to get them on side before Paris.

The third factor was the efforts of the French diplomatic system. We were blessed here in Ireland by having a very active French ambassador who was himself a negotiator at Kyoto in his earlier days and who also worked actively behind the scenes within the Irish system here. As part of a large scale effort in the global sense, the French diplomatic system worked very hard. President Hollande visited most of the key people at least once over the course of the previous year.

The fourth factor, which was quite influential behind the scenes, was the Papal Encyclical, Luadato si'. Here was something which was written in plain English, which was not overburdened by theology but which could actually bring the message home to people in a very effective way. It has had a profound background effect on many of the political figures around the world since its publication in June.

All of this set the scene for a conference which one sensed would be different right away when one arrived in Paris. The mood was different from all the other COPs I have attended. There was a feeling that an agreement would emerge and so it did. After the third day of the second week, the optimism dissipated briefly when things went down on paper and negotiators did not see their pet projects appearing, but the process was resurrected and quite a considerable framework agreement was achieved. That is the important point today. It is a framework agreement which puts the ball back in countries' courts. It is up to countries now to live up to the obligations they made.

I can address a couple of the other points briefly. The point Deputy Eric Bryne raised about the River Shannon was a very valid one. It brings home to us the consequences at a local level of what is happening at a global level. To provide a snippet of scientific research published by the UK Met Office in December, it estimated that the probability of a ten-day extreme rainfall event such as the UK had experienced had increased seven-fold as a result of the loading of the atmosphere with greenhouse gases. The research was based on a very comprehensive modelling effort. It brings home to us the fact that we face a greatly increased hazard. There are adaptation responses we can make to that. The Deputy is right that we can with judicious planting reduce flood hazard in some places. With judicious planting of forest, we can gain some sequestration of carbon which will help us with our obligations in the future. We have to be very careful where we plant new forests, however. If we plant them in carbon rich soils and remove the carbon from that soil as a consequence, we are actually undoing some of the benefits we would otherwise achieve. It has to be done with a very careful policy in mind.

In terms of farming, the farmers of Ireland are among those I admire most in the country. They are excellent farmers and stewards of the landscape. We have to face the idea of rewarding them by putting some of the single farm payment towards farmers who are willing to let lands close to the Shannon flood in the winter time to allow that reservoir of water to be stored for a while rather than to run down the river to flood high amenity urban land elsewhere. We need thinking out of the box on how we manage the area around the Shannon. It has been a bugbear as we know for almost a century at this stage, but there are options available.

In terms of what we should be doing and what we would we do not like about the Paris agreement, the most significant decision was the ratcheting effect. That is the effect whereby every five years a country must come back with increased efforts. That may not sound all that bad now but if it is implemented and one multiplies it by ten, 15 or 20 years, it will mean getting to grips with the problem.

The most disappointing thing for me was the absence of shipping and aviation from the agreement. Those very powerful interest groups managed to get themselves excluded. If one adds up the emissions from shipping and aviation globally, they account today for the combined emissions of the UK and Germany. It is a very substantial loss. We hope that the aspirations and commitments they made to tighten up their emissions and avoid burning high sulphur and heavy fuel oil where it is unnecessary will begin to produce results in that area.

Oil prices are a problem as Deputy Olivia Mitchell was saying. It is a two-edged problem. As oil prices fall, fertilizer costs for the developing world will also fall so that some farmers in developing countries will benefit considerably from their ability to farm more efficiently. For some of the large developing countries like India and Brazil, it may be more of a problem and it may well be that they would prefer higher oil prices. We have to think about how we are going to spend the taxation from energy in that situation of falling oil prices. Should we ring-fence more of it towards encouraging renewable energy for example?

I was asked what I would change in the climate legislation. The awareness issue raised by Deputy Maureen O'Sullivan is very important. The budget for climate awareness in the last five years has been very small indeed and not much has been spent to enhance climate awareness in Ireland apart from initiatives like the encouragement of the green schools system. I would like to see more of that. Responsibility and policy coherence are critical here. I would have hoped that responsibility for the climate change Bill would have been taken by the Department of the Taoiseach rather than left to individual silos to fight their corners individually. That has been a bugbear which has affected progress on mitigation over the last few years.

I was asked about animals and plants. We tend to forget about biodiversity. The person who asked the question was right. The Papal encyclical was actually very strong on the point that we share the planet with other organisms and have no right to render them extinct to suit our own needs. It is a very valid ethical point which we have to take cognisance of.

I have talked enough and should pass on to someone else at this point.