All countries and their inhabitants are responsible for the future of the Earth, especially the new generations that will inherit a world in a coma, so it is not only necessary to re-educate ourselves in terms of habits of lifestyle and consumption, but also to assume that politics, through the vote, gives citizens the opportunity to favor those who are seriously committed to the urgency that climate change imposes on us. The Conference of the Parties of the United Nations on Climate Change, for its acronym in English, COP, will hold its 25th annual meeting in Santiago de Chile between December 2 - 13 of the current year. Heads of State and/or governments shall adopt agreements and measures aimed at mitigating the effects of human action that are already evident in all continents and in each of the countries. Previously, in Costa Rica, the preparatory meeting or Pre-COP 25 will be held between October 8 and 10, and this is where negotiators and technical teams will discuss and analyze the proposals to be presented at the conference. This means that Latin America will be the scene of one of the meetings that could be decisive to impose rationality, strengthen multilateralism and the commitment of governments, the private sector, academia and civil society to take concrete measures aimed at leaving the state of inertia behind, recovering lost time and reducing emissions before it is too late for everyone.

There is consensus in the academic world that approximately since 1850 the increase in emissions has had a geometric progression in the world. While all countries are responsible for increasing emissions, some are more than others. The issue today is not to blame those who have emitted more, but rather to discuss which concrete steps we must take to stop and/or reduce them. We know that the growing use of fossils is one of the main causes of the increase in CO2, and we are aware that it is not realistic to think that their use will end overnight. This will be a process, depending on the political will of governments or of the agreements that can be adopted internationally. Although since the beginning of the COP, in Rio de Janeiro in 1992, greenhouse gases have not stopped rising, they have managed to slow their increase as well as generating a positive effect on citizens and governments that have increased the use of renewable resources. That is why it is essential to know what the great powers will do, and we hope that the United States will again become part of this conference. What measures will countries such as China, Germany, France, India or Brazil propose? We do not know, but the world expects their contribution in order to avoid a catastrophe.

Recently, the journal Science published a complete study carried out by a multidisciplinary scientific team funded by Germany and with the support of the Zurich Institute of Technology (ETH) and FAO, which features a nature-based solution to mitigate emissions temporarily in a significant way. It consists of a global plan for restoration of degraded land and reforestation that would comprise some 900 million hectares, equivalent to one billion (this is a 1 plus 12 zeros) of new trees, which would have a planetary impact because they are an efficient natural agent absorbing the CO2 that humans produce. If we achieve this plan, in the next 20 years emissions could be balanced, and during this period the concentration of gases in the atmosphere would not be aggravated. Countries would have reasonable time to implement other -more capital intensive- alternatives using less polluting energy and means of transport as well as to rethink the growth model.

The technical proposals therefore exist, and it is possible to put them into practice in the course of a generation that could be the last to have the possibility of curbing climate change. It only requires a small detail: the political will of governments to carry it out. It is a unique possibility for giving multilateralism an opportunity to materialize a government agreement which initiates a global plan for restoration of degraded land and reforestation. We know all about the available space, we know the costs and the time it would take to perform this gigantic task. A precursor idea known as the Bonn Challenge, which in a decade restored millions of degraded hectares around the world, showed that an alliance between the private sector and governments is possible - as has been done in Germany -, allowing for the identification and initiation of restoration of 350 million hectares at the planetary level. The new challenge of the ETH and FAO study, after identifying degraded lands, is to multiply the Bonn Challenge by three without competing with land destined for food production, nor with urban areas and can be started immediately. The studies carried out suggest it as the lowest-cost global option, estimating that with 300 billion dollars, the bulk of the program would be implemented. Therefore, this investment is infinitely less than others that border 1% of global GDP annually.

Therefore, an implementation scenario can be proposed for three sub-regions of the world.

1. America. In the current circumstances it is likely that the United States won’t participate at federal level, but that some of its states would. You can count on countries like Canada, Mexico and Brazil, which would be joined by most of the others in the region. Together they could multiply efforts and reach the equivalent of one third of the overall goal.

2. Europe and Africa. They can develop a massive restoration plan by expanding the activities undertaken today by 11 African countries in the Great Green Wall. Europe would provide the funds and Africa the land and the workforce, which would add a second third of the final objective.

3. Asia. An effort on that continent, led by China, India and Russia, with financial support from Japan, Australia and Korea and involving all island states, could reach the last third necessary to give humanity a break for the next 20 years.

International Organizations cannot be blamed for the current state of the planet, but one should bear in mind that they are only executors of what the governments of their member states authorize. COP 21, held in Paris in 2015, was the first binding agreement between all countries at a global level on the climate - and immediately the United States announced its withdrawal. Today the scientific evidence has left no doubt about the effect of human action. So, what can we expect from the next meetings in Costa Rica and Chile? It will depend on how much the dramatic increases in temperature, droughts and floods which we are witnessing have affected public opinion and governments. The year 2019 will be remembered as the one that has registered the highest temperatures since there are records. But it could be or will surely be worse in the coming years. Climate change is not an ideological problem, it is one of survival.

In forestry, Chile and Costa Rica have led by example and can now promote this global initiative.

Article by René Castro, former Minister of Foreign Affairs, Environment and Energy of Costa Rica, FAO Deputy Director General in charge of climate change and Fernando Ayala, former Ambassador of Chile, FAO consultant. Translation from Spanish by Anke Kessler.