The world is increasingly at risk of “climate apartheid”, where the rich pay to escape heat and hunger caused by the escalating climate crisis while the rest of the world suffers, a report from a UN human rights expert has said.

Philip Alston, UN special rapporteur on extreme poverty and human rights, said the impacts of global heating are likely to undermine not only basic rights to life, water, food, and housing for hundreds of millions of people, but also democracy and the rule of law.

Alston is critical of the “patently inadequate” steps taken by the UN itself, countries, NGOs and businesses, saying they are “entirely disproportionate to the urgency and magnitude of the threat”. His report to the UN human rights council (HRC) concludes: “Human rights might not survive the coming upheaval.”

The report also condemns Donald Trump for “actively silencing” climate science, and criticises the Brazilian president, Jair Bolsonaro, for promising to open up the Amazon rainforest to mining. But Alston said there were also some positive developments, including legal cases against states and fossil fuel companies, the activism of Greta Thunberg and the worldwide school strikes, and Extinction Rebellion.

In May, Alston’s report on poverty in the UK compared Conservative party welfare policies to the creation of 19th-century workhouses. Ministers said his report gave a completely inaccurate picture, but Alston accused them of “total denial of a set of uncontested facts”.

Alston’s report on climate change and poverty will be formally presented to the HRC in Geneva on Friday. It said the greatest impact of the climate crisis would be on those living in poverty, with many losing access to adequate food and water.

“Climate change threatens to undo the last 50 years of progress in development, global health, and poverty reduction,” Alston said. Developing countries will bear an estimated 75% of the costs of the climate crisis, the report said, despite the poorest half of the world’s population causing just 10% of carbon dioxide emissions.

“Yet democracy and the rule of law, as well as a wide range of civil and political rights are every bit at risk,” Alston’s report said. “The risk of community discontent, of growing inequality, and of even greater levels of deprivation among some groups, will likely stimulate nationalist, xenophobic, racist and other responses. Maintaining a balanced approach to civil and political rights will be extremely complex.”

The impacts of the climate crisis could increase divisions, Alston said. “We risk a ‘climate apartheid’ scenario where the wealthy pay to escape overheating, hunger, and conflict while the rest of the world is left to suffer,” he said.

“When Hurricane Sandy wreaked havoc on New York in 2012, stranding low-income and vulnerable New Yorkers without access to power and healthcare, the Goldman Sachs headquarters was protected by tens of thousands of its own sandbags and power from its generator.”

Alston strongly criticises all those working to uphold human rights, including his own previous work, for not making the climate crisis a central issue. He said the most recent HRC resolution on the climate crisis did not recognise “that the enjoyment of all human rights by vast numbers of people is gravely threatened” or “the need for the deep social and economic transformation, which almost all observers agree is urgent if climate catastrophe is to be averted”.

Q&A Why is the Guardian changing the language it uses about the environment? Show The Guardian has updated its style guide to introduce terms that more accurately describe the environmental crises facing the world. Instead of “climate change”, the preferred terms are “climate emergency, crisis or breakdown” and “global heating” is favoured over “global warming”. The scale of the climate and wildlife crises has been laid bare by two landmark reports from the world’s scientists. In October 2018, they said carbon emissions must halve by 2030 to avoid even greater risks of drought, floods, extreme heat and poverty for hundreds of millions of people. In May 2019, global scientists said human society was in jeopardy from the accelerating annihilation of wildlife and destruction of the ecosystems that support all life on Earth. The editor-in-chief, Katharine Viner, says: “We want to ensure that we are being scientifically precise, while also communicating clearly with readers on this very important issue. The phrase ‘climate change’, for example, sounds rather passive and gentle when what scientists are talking about is a catastrophe for humanity.” Other terms that have been updated include the use of “wildlife” rather than “biodiversity”, “fish populations” instead of “fish stocks” and “climate science denier” rather than “climate sceptic”. Damian Carrington Environment editor

International climate treaties have been ineffective, the report said, with even the 2015 Paris accord still leaving the world on course for a catastrophic 3C (equivalent to an increase of 5.4F) of heating without further action. “States have marched past every scientific warning and threshold, and what was once considered catastrophic warming now seems like a best-case scenario,” the report said.

The US president is one of the few individuals named in the report. “He has placed former lobbyists in oversight roles, adopted industry talking points, presided over an aggressive rollback of environmental regulations, and is actively silencing and obfuscating climate science.”

However, the required changes to societies and economies could be an opportunity to improve poor people’s lives, Alston said. “This crisis should be a catalyst for states to fulfil long ignored economic and social rights, including to social security and access to food, healthcare, shelter, and decent work,” the report said.

Ashfaq Khalfan at Amnesty International said: “Climate change is a human rights issue precisely because of the impact it’s having on people. The primary obligation to protect people from human rights harms lies with states. A state that fails to take any feasible steps to reduce greenhouse gas emissions is violating their human rights obligations.”

He said Amnesty planned to target governments and fossil fuel companies. “We need everybody to live up to their responsibilities to act on climate change and protect human rights,” he said.