The largest glacier in the Swiss Alps, the Aletschgletscher, is melting rapidly and could disappear altogether by 2100. Geir BraathenThe world’s climate is changing rapidly and these changes are evident on a daily basis. Global temperatures are rising, rainfall patterns are changing and the weather in many parts of the world is more erratic and unpredictable than ever before. The effects are widespread; natural habitats are changing, biodiversity is being lost, farming cycles are being disrupted and water stress is becoming more common than not. Natural hazards such as floods, droughts, hurricanes and heatwaves are becoming more extreme and frequent costing countries billions of dollars and destroying homes, infrastructure and livelihoods. The climate crisis is threatening people’s well-being, food security and worsening poverty.In June this year, the UN Secretary-General said the world needs to create conditions for “harmony between humankind and nature.”What is meant by a nature-based solution?Nature-based solutions are actions that protect, sustainably manage, and restore natural or modified ecosystems, that also address societal challenges, thereby simultaneously providing human well-being and biodiversity benefits. So, whether its food security, climate change, water security, human health, disaster risk or economic development, nature can help us find a way. And climate change is a very important part of the solution puzzle. There are many ways to address climate change, but one of the most effective and immediate ways is using what is on our door step… nature. For example, nature-based solutions can focus on reducing emissions from deforestation and agricultural practices and enhancing the ability of natural ecosystems to remove carbon dioxide from the atmosphere. Remember, it is carbon dioxide that contributes to the greenhouse gases that lead to global warming.The UN Secretary-General’s Climate Action Summit provides an opportune moment to catapult nature-based solutions to the forefront of climate action. What range of solutions are available?Most nature-based solutions for climate change come from strengthening or restoring existing natural ecosystems. For example, forests don’t just absorb carbon, they also defend us from its most devastating impacts. Carefully planted tree species can act as firebreaks, keeping trees next to farmland can protect crops from the erosive forces of intense rain, and forests can alleviate inland floods due to the sponge-like way they absorb water. World leaders will be gathering at the United Nations in New York next week at a Climate Action Summit convened by the UN Secretary-General António Guterres and Ms. Andersen will be there to promote the idea of nature-based solutions to combatting climate change.UNEP is supporting one of the nine summit action tracks designated by the Secretary-General under the leadership of the Governments of China and New Zealand. UN News asked Ms. Andersen how nature can help to reverse climate change.How is climate change affecting the natural world? Mangroves provide effective and cheap natural barriers against coastal floods and shoreline erosion. Changing our land practices alone could deliver 30 per cent of the emissions reductions that we need to achieve the goals of the Paris Agreement on climate action by 2030.Restoring peatlands and other natural ecosystems are also effective nature-based solutions. Find out more here about the benefits of peatlands: How effective are they and at what financial cost?Nature is available now and we should use it; there are no quick technological fixes that have the same scale of impact that nature-based solutions offer. In fact, these solutions could deliver more than a third of the emissions reductions needed globally by 2030. Crucially, what is urgently required is an increase in investment to unlock the potential of nature. Right now, these solutions receive less than three per cent of available climate funding, even though they are extremely cost effective. And, they offer a very high return on investment potentially adding trillions of dollars to the global economy. For example, the building of the Great Green Wall an ambitious project to reverse desertification in the Sahel region of Africa could create 10 million jobs there by 2030 and have other benefits including slowing migration.These solutions have to be integrated into climate adaptation and mitigation efforts. Globally, governments must align their efforts and commit to investing in these solutions as part of their national policies. How important are nature-based solutions in the overall fight against climate change?The bottom line is that we cannot limit warming to 1.5°C (or 2°C for that matter) without natural climate solutions. Nature-based solutions have the potential to reduce emissions of carbon dioxide by 12 gigatons each year. This is roughly equal to emissions from all the world’s coal fired plants. At the same time, it is important to keep in mind, firstly, that increasing ambition requires us to commit simultaneously to an energy transition and greater investments in nature. And secondly, if we don’t act on nature now, then nature’s ability to protect humanity will diminish even more. So, nature is on the table as a solution to climate action, but only just and we have to seize the moment. The good news is nature is forgiving and it’s time we gave it the chance it deserves. Are there enough projects underway right now globally to make a difference? The Executive Director of the UN Environment Programme, Inger Andersen, addresses a meeting in Nairobi, Kenya. UNEP/Cyril VillemainWe are in a period of global emergency, but also in a period of unprecedented momentum. Young people are holding us to account, and every week a government somewhere in the world, commits to climate action. Nature-based solutions are immediately available, cost-effective and can be scaled up depending on need. And every country in the world can act. And we have many examples of success. When the Great Green Wall is completed in 2030, restored land will absorb carbon dioxide equal to keeping all of California’s cars parked for 3½ years. In Niger, farmer-led reforestation has improved tree cover, reducing women’s time in collecting firewood from three hours to 30 minutes. And Medellin in Colombia reduced temperatures by more than 2°C through turning their concrete jungles into urban forests.So, we need to scale up initiatives like this, build on political momentum and deliver at the scale and pace needed to propel us beyond the ambitions of the Paris Agreement because when we give nature a chance, we have a better shot at achieving the Sustainable Development Goals.