oe Biden is set for a flurry of action to combat the climate crisis on his first day as US president by immediately rejoining the Paris climate agreement and blocking the Keystone XL pipeline, although experts have warned lengthier, and harder, environmental battles lie ahead in his presidency. In a series of plans drawn up by Biden’s incoming administration for his first day in office, the new president will take the resonant step of bringing the US back into the Paris climate accords, an international agreement to curb dangerous global heating that Donald Trump exited. The Democrat, who will be sworn in on Wednesday, is also set to revoke a permit for the Keystone XL pipeline, a controversial cross-border project that would bring 830,000 barrels of crude oil each day from Alberta, Canada, to a pipeline that runs to oil refineries on the US’s Gulf of Mexico coast. The president-elect is also expected to reverse Trump’s undoing of rules that limited the emission of methane, a potent greenhouse gas, from oil and gas drilling operations. “Day one, Biden will rejoin Paris, regulate methane emissions and continue taking many other aggressive executive climate actions in the opening days and weeks of his presidency,” said Paul Bledsoe, who was a climate adviser to Bill Clinton’s White House, now with the Progressive Policy Institute. Bledsoe said Biden’s nominees to tackle the climate crisis, spearheaded by the former secretary of state John Kerry, who will act as a climate “envoy” to the world, is “by far the most experienced, high-level climate team US history. They intend to hit the ground running.” The aggressive opening salvo to help address the climate crisis, which Biden has called “the existential threat of our time”, is set to include various executive orders to resurrect a host of pollution rules either knocked down or weakened by the Trump administration. The US will convene an international climate summit in Biden’s first few months in the White House and is set to join a global effort to phase out the use of hydrofluorocarbons, or HFCs, which are used in refrigeration and air conditioning and contribute to the heating of the planet. Biden has also vowed to support federal government scientists beleaguered by years of climate change denial and sidelining of politically inconvenient science by the Trump administration. “It will be a starkly different approach to the Trump administration on almost every front,” said Helen Mountford, vice-president for climate at the World Resources Institute. “Science will once again guide America’s policymaking and inauguration day will mark a new era for climate ambition in the US. He will have a lot on his plate but there’s no doubt that Biden intends to make a full court press on climate change.” However, climate experts point out that simply re-establishing Barack Obama’s climate policies will not be enough to help the world avoid the worst ravages of heatwaves, flooding and mass displacement of people. “It’s not sufficient for where the science says we need to be and it’s not sufficient because we’ve lost critical time over the last couple of years,” said Brian Deese, Biden’s nominee for director of the National Economic Council. Planet-heating emissions dipped in 2020 due to the coronavirus pandemic but are already surging back to previous levels despite the UN warning countries must at least triple their emissions cuts promised under the Paris deal. Biden has pledged to cut US emissions to net zero by 2050 and has a $2tn plan he claims will create millions of new jobs in energy efficient retrofits for buildings and clean energies such as solar and wind. These ambitions have been bolstered by Democrats’ slender control of the US Senate, although several of the party’s senators, such as West Virginia’s Joe Manchin, who once shot a piece of climate legislation with a gun in a TV campaign advertisement, are wary of big-spending climate bills. US lawmakers have been divided and inert on climate legislation for a decade, despite polls showing record bipartisan support for climate action among the American public. The outcome of the political wrangling will be most keenly felt by poorer people and people of color who disproportionally live near sources of air and water pollution such as coal-fired power plants and highways. Biden has promised to help these communities but will need to “put his money where his mouth is”, said Mustafa Santiago Ali, a former senior official at the Environmental Protection Agency. “Folks will be more focused on the greenhouse gas side of the paradigm, which is maybe a quarter of the work,” Ali said. “There needs to be a comprehensive federal strategy for environmental justice. We have to rebuild trust with communities that we took decades to build up and then was broken. The bogeyman, which is Trump, may be gone but we still need to focus on dismantling that structural environmental racism. Trump just threw more gasoline on what was already there.”