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"Governments are better informed than ever to be able to make scientifically sound decisions towards decarbonisation."

Canadell, UAB alumni and scientific advisor to CREAF, described the moment in which we are in, with an average increase in temperature of 1.2 ºC in comparison to pre-Industrial Revolution times due to greenhouse gas emissions. He also spoke on the impacts already being experienced. As one of the most influential scientists in the world on issues related to ecology, he emphasises the need to act quickly and globally if we want to stop this continuous increase in emissions in which we now find ourselved.

— Will we manage to limit the increase in global warming to 2 ºC by 2030 as set down in the Paris Agreement?

— At this moment, the tendency in fossil fuel emissions and other greenhouse gases is increasing and with the national policies in force around the world we will reach an increase in temperature that is much higher than the 2 ºC increase since the pre-industrial period.

— What role do fossil fuels play in global warming?

— There are many sectors producing greenhouse gases that cause global warming, but the most important source is fossil fuels, mainly gas, coal and oil. These emissions have been growing since the beginning of the Industrial Revolution in the order of billions of tonnes each year. Carbon dioxide, which is the most important gas, accumulates in the atmosphere and remains for thousands of years. To stabilise climate change, which is not hte same as solving the problem, these emissions have to go to net zero: what is emitted for what is captured. Moreover, within fossil fuels there is also methane, which is much more potent than carbon dioxide, and which continues to grow and accumulate emissions. The only advantage is that, if we stop or reduce them, we will soon see a reduction in global warming due to this gas.

— What will happen then, if we pass this 2ºC limit?

— What is already happening now, when we have a global average increase of 1.2 ºC? Globally, in the past ten years four billion people, half the world's population, have suffered and experienced weather extremes they had never before seen in their lives. And all of this is happening with a very low level of increase. What we are learning now is that even the 2 ºC of the Paris Agreement is too much. Ten or twenty years ago our goal was to avoid the worst-case scenarios of 4 or 5 ºC increases. But now we see that even with lower emissions the impacts will be very significant for human health, ecosystems, and overall quality of life, and that we will need to address major adaptation strategies. Even if we manage to stay at 1.8 or 1.9 or 2 ºC above pre-industrial levels, which does not appear to be the case, there will be a very significant warming with a high level of impacts even here in Catalonia. 

— What effects can we see in weather events such as drought, fires and flooding?

— Now we already have the imprint of climate change in many extreme phenomena. Not all of them, because the climate system is very variable in a natural way and, therefore, we have to extract the anthropogenic component from the natural component. But what we see is that events such as heat waves last longer, are more frequent and more extreme; as well as heat waves in the ocean. Shorter rainfalls, lasting less than half a day, that lead to flooding in many parts of the world and certainly in Europe and the Mediterranean, have increased and intensified. Fire weather is becoming more intense and frequent. We have very good statistics from many parts of the world, from the Mediterranean region, from the great boreal forests of Canada and Siberia, from much of the United States and Australia, where we see distinctively a very rapid increase in the areas burned and the carbon dioxide emissions coming out of these areas.

— Do we have a very local view on the effects of climate change?

— When we talk about climate change, if we don't become global citizens and believe it, we won't solve it. We all live on the same planet, with a shared atmosphere - let's try to develop a global society, we are citizens of the world! If we do not have a global perspective in which we help each other to decarbonise the planet, we will not succeed. Here we are only thinking about ourselves and the nuclear power plants, which will be shut down in 2033, and what we will do. But Catalonia, as a developed, rich and intelligent country, has to do more. We have to do our decarbonisation here and we have to help the world to do it. We have to help, give support and technologies to other countries that need it, we have to show solidarity and help them to decarbonise. And it is also very important to have initiative and leadership. And here in Catalonia I don't see a strong leadership.

— Are you surprised that there are still people denying climate change?

— During the 1990s and 2000s, denialism was very strong, had a lot of influence on governments and was very important in the battle we had with the big multinational fossil fuel companies. Now, in 2024, we think it no longer has a voice. The population understands better what climate change is and what produces it and governments, through the very big efforts we make, for example from the Intergovernmental Panel on Climate Change (IPCC) of the United Nations, are very well informed of what is going on. All this denialist noise is becoming less and less noisy, although now they have the new tactic of making the changes as slow as possible. These are very difficult battles to win individually, but governments are better informed than ever to be able to make scientifically sound decisions towards decarbonisation.

— Yet, at the UN Climate Change Conference, or COP 28, at the end of last year, there were no binding declarations from governments.

— It was not the goal for countries to come to the table with more restrictive emission mitigation targets than before. It is next year when they will have to establish what they want to do by 2035. But there was one interesting aspect, which was to put on the negotiating table the food production system, which has not been talked about much. In this system we have an excess of nitrogen, which comes from the excessive use of fertilisers and slurry, and from animals for the meat industry. For the first time, the need to apply innovations in technologies that can help reduce emissions was discussed. There are always decisions to move towards decarbonisation, the big disappointment is that they are not taken fast enough.

— Are there countries managing to reduce their emissions while maintaining their economies?

—  Yes, there are already 26 countries with this mitigation trend and with economies that are growing. They are sufficiently diverse, not only countries like Norway, for example, but also from Africa and Asia, and many European countries, which are also different from each other. They all, in one way or another and for different reasons, want to accelerate renewables. It is a good time to analyse all these cases and learn what we can apply at home for the emissions profile we have, which in Catalonia is unique and different from all those other countries. We have to develop our own decarbonisation pathway. There is a lot of experience and technology that we do not have to develop ourselves, but we have to know how to adapt it.

— What type of technology needs investment?

— The most important to start with is the power grid. This grid has to be 100% renewable, clean and it has to grow. It has to be even more interconnected than it is now, because this can then support the decarbonisation of many other sectors. The mobility sector is the clearest. We have no doubt what the future of mobility is, now we no longer talk about whether it will be biofuels or hydrogen, we know it is electrification.

— Is a new Industrial Revolution necessary?

— A new Green Industrial Revolution, which implies replacing all greenhouse gas emitting components of all economic sectors. And this involves issues such as how we make energy, how we move and how we produce food. We need a lot of solar panels and a lot of wind turbines to do this decarbonization process and also to be able to electrify as much of our economy as we can, such as heating our homes. Now we know that by transforming it and electrifying it we will save primary energy and, if we set up this electricity grid that has no emissions, we do two things at the same time: we stop emissions and we become much more efficient. The roadmaps serve to analyse sector by sector what can be electrified and explore possible solutions for what cannot be done to reduce emissions.

— And what will be the role of forests in decarbonisation?

— We are saying that we have to have net zero emissions by 2050, but we are sure that we will not achieve that. There will be a percentage of emissions, 10 or 15%, that we will not be able to stop emitting. We may have machines to eliminate emissions, but developing them will be very expensive. We need to consider the carbon dioxide sinks provided by forests, crops and the landscape in general. We need to explore win-win strategies. We can have a more restored, resilient and renewed landscape that captures those residual emissions that we are not able to remove completely or that are ridiculously expensive to remove technologically.