Millions of people around the world are facing disaster from flood, droughts, heatwaves and other extreme weather, as governments fail to take the measures needed to adapt to the impacts of climate breakdown, the UN has warned. Nearly three-quarters of countries around the world have recognised the need to plan for the effects of global heating, but few of those plans are adequate to the rising threat, and little funding has been made available to put them into force, according to the UN environment programme’s Adaptation report 2020, published on Thursday. Last year was the joint hottest on record, with a heatwave in Siberia, wildfires in Australia and the US, a destructive Atlantic hurricane season and storms and floods in many parts of Asia. But spending on measures to adapt to extreme weather has failed to keep pace with the rising need, according to UNEP. Only about $30bn (£22bn) is provided each year in development aid, to help poor countries cope with the effects of the climate crisis, which is less than half of the $70bn currently estimated to be needed. Those costs are set to increase further, to between $140bn and $300bn by the end of the decade. About half of global climate finance should be devoted to adaptation, the UN secretary-general, António Guterres, has said, with the rest going to efforts to reduce greenhouse gas emissions. However, while private companies are often willing to provide funding for some projects to reduce emissions, such as profitable renewable energy generation schemes in rapidly emerging economies, projects that help people adapt to the impact of climate change, such as early warning systems, flood barriers or storm drains, are often more difficult to finance. Many countries will also struggle to find the resources for climate adaptation because of the coronavirus pandemic, the UN warned. The economic impacts of Covid-19 have pushed adaptation further down the political agenda across the world, while in the longer term the consequences of the pandemic are likely to put additional pressures on public finances, and “might change national and donor priorities in support of climate action”. The UK government recently slashed its overseas aid budget, though the climate spending portion has been maintained. Yet if countries were to prioritise a “green recovery” in their Covid-19 economic stimulus packages, they could help to solve many of these problems, UNEP noted. Economic studies have shown that measures to increase resilience to the impacts of the climate crisis – including planting trees, building flood barriers, restoring natural landscapes and protecting and updating infrastructure such as transport and communications networks – can all provide “shovel-ready” jobs of the kind needed to lift economies out of recession. That opportunity will be missed if countries stick to the economic rescue packages announced to date, which so far have failed to focus on a green recovery, according to the report. The report also found that nature-based solutions should be prioritised. These include planting trees to act as carbon sinks, and as natural flood barriers; restoring mangrove swamps as buffers against coastal storms and sea level rises; halting the destruction of coral reefs; re-wetting bogs and wetlands; and allowing areas of degraded land to regenerate naturally. These tend to be among the most cost-effective ways to adapt to extreme weather, and many also help to reduce greenhouse gas emissions, as healthy soils, vegetation, seas and landscapes store more carbon than degraded land and seas. Reducing greenhouse gas emissions, while an important priority, will not be enough to erase the need to adapt to increasing extreme weather. The report found that the world would face a rising toll from climate impacts, even if the goals of the Paris agreement – limiting temperature rises to well below 2C, with an aspiration of holding heating to 1.5C above pre-industrial levels – are met. Temperatures have already risen by 1C above the historic norm. Inger Andersen, the executive director of UNEP, said: “We are not saying we can adapt our way out of climate change, but the impacts of failing to invest in adaptation to climate change will be very severe, and it is the poorest in wealthy countries and the poorest in the world who will pay the highest price, and who are most exposed to these impacts.” She said extreme weather events were already taking a toll, so governments should see adaptation as an urgent issue. “The more we can expedite adaption investments, the lower the human costs and the economic costs will be,” she said. “It makes good sense for society.” While governments are struggling with the impacts of the coronavirus pandemic, they should plan to use stimulus money with a view to making their countries more resilient to the impact of the climate crisis. “There is a massive injection of the next generation’s money into the Covid recovery – are we going to leave the next generation with a massive debt as well as a broken planet?” She said the first wave of stimulus spending had not prioritised green investment, but that further waves of spending should do so. “There are opportunities here,” she added.