Victory for Donald Trump in the US presidential election this year could put the world’s climate goals at risk, a former UN climate chief has said. The chances of limiting global heating to 1.5C above pre-industrial levels are already slim, and Trump’s antipathy to climate action would have a major impact on the US, which is the world’s second biggest emitter of greenhouse gases and biggest oil and gas exporter, said Patricia Espinosa, who served as the UN’s top official on the climate from 2016 to 2022. “I worry [about the potential election of Trump] because it would have very strong consequences, if we see a regression regarding climate policies in the US,” Espinosa said. Although Trump’s policy plans are not clear, conversations with his circle have created a worrying picture that could include the cancellation of Joe Biden’s groundbreaking climate legislation, withdrawal from the Paris agreement and a push for more drilling for oil and gas. Espinosa said: “We are not yet aligned to 1.5C. That’s the reality. So if we see a situation where we would see regression on those efforts, then [the likelihood of staying within 1.5C] is very limited. It would certainly be a much bigger risk. “We could see a slowdown, an even bigger slowdown [in action to reduce emissions], which would unfortunately probably take us to an even more terrible scenario, unless we see strong leadership coming from other places, [such as] Europe.” She said other countries must continue with climate action even if the US were to renege on its goals under Trump, but the absence of the US would be a significant blow. “What happens in the US has a very big impact in so many places around the world,” she said. It is not all gloom, however. Espinosa was the executive secretary of the UN framework convention on climate change, parent treaty to the 2015 Paris agreement, in 2016 when Trump was elected president. She said that if other countries put up a united front in favour of strong climate action, it could help to counteract the absence of the US. “When President Trump announced that they would withdraw from the Paris agreement, there was a certain fear that others would follow, and that there would be a setback in the pace of the climate change process. Not only did that not happen but some countries that had not yet adhered to the Paris agreement did so,” she said. If Trump were to take the US out of Paris in a fresh term, she does not believe others would follow suit. “As of now, I don’t see countries really going back. I think that the process will continue.” On the contentious issue – particularly for the US – of climate finance, Espinosa said Biden was now facing difficulty in getting climate finance commitments through a hostile Republican Congress. “We are seeing a lack of leadership, including in the big countries that can make contributions,” she said. “[In the US] I think there is a willingness but there are also limitations. In the EU there has been a long period where they have been discussing the internal frameworks [for climate finance]. At the same time, we have been seeing a reduction of funds going in general to the global south, and very little is going to climate change. It’s really a question of giving it priority.” She is also concerned that too much of the focus of climate finance and efforts to reduce emissions so far has been on shifting from a reliance on fossil fuels to renewables. “We are now realising that nature will make or break net zero – decarbonising the energy sector will not be enough,” Espinosa said, calling for more emphasis on the role of nature, to halt deforestation and transform food production, which accounts for about a third of global emissions. “The 1.5C economy can only be achieved by ending deforestation and accelerating the transition to sustainable agriculture and food systems this decade.” In 2024, most of the world’s population will go to the polls in elections, in the US, Russia, India, the UK and scores of other countries. Climate action will be a contentious issue in many of these elections, as some parties are arguing for stronger policies based on stark scientific warnings, while others oppose such action. Espinosa warned of the opposition to climate action that is being orchestrated around the world. “In the US, we see a very well organised and very strong campaign intending to reduce the perception of the critical nature of action that needs to be taken.” To combat this, she called for businesses to play a greater role in pushing for a low-carbon economy. “We need to work closely with the private sector, make them aware of the important opportunities that the new [low-carbon] economy provides. There are profitable investments that protect nature and innovate technologies.”