President Joe Biden desire to re-establish US leadership on the climate crisis will face a severe test this week at a summit the president hopes will rebuild American credibility and kickstart a spluttering international effort to stave off the effects of global heating.

Biden has invited 40 world leaders to a two-day virtual gathering starting on Earth Day, Thursday, as the opening salvo in negotiations leading to crunch United Nations talks in Scotland later this year. Scientists say the world is severely lagging in tackling the climate crisis and its heatwaves, storms and floods, with planet-heating emissions set to roar back following a dip due to coronavirus shutdowns.

Joe Biden faces major test building US credibility at climate summit
President will unveil new emissions reduction target while much will hinge upon cooperation between China and US

Much will hinge upon cooperation between China, the world’s worst producer of planet-heating emissions, and the US, historically the worst polluter. On Saturday, John Kerry, Biden’s climate envoy, struck an agreement in Shanghai to urgently address what Kerry called the “beyond catastrophic” consequences of allowing temperatures to spiral upwards.

The compact is broadly seen as encouraging but comes amidUS-China tensions on issues including human rights and trade. The US also faces a deficit in credibility after the presidency of Donald Trump, which saw the country leave the Paris climate accords and dismantle environmental protections.

Biden has returned the US to the Paris agreement but a spokesman for the Chinese foreign ministry said the move was “by no means a glorious comeback but rather the student playing truant getting back to class”.

The US is suffering from a “credibility gap” due to years of oscillating policy, according to Josh Busby, an expert in climate governance at University of Texas-Austin.

“The US return to climate diplomacy may be taken seriously so long as the Biden administration can keep its climate policy agenda alive,” he said.

On Monday Antony Blinken, the secretary of state, acknowledged America was “falling behind” China in producing solar panels and electric vehicles but promised a muscular approach in prodding other countries to do more.

“Our diplomats will challenge the practices of countries whose action, or inaction, is setting us back,” Blinken said.

“When countries continue to rely on coal for a significant amount of their energy, or invest in new coal factories, or allow for massive deforestation, they will hear from the United States and our partners about how harmful these actions are.”

The centerpiece of Biden’s summit will be the unveiling of the new US emissions reduction target, which may be the only significant new pledge at the event. The goal is expected to be at least a 50% cut by 2030, based on 2005 levels, a target broadly backed by environment groups as well as the UN secretary general, António Guterres, who has said 2021 “must be the year for action” to avoid an “abyss” of climate disaster.

Anything below a 50% cut will be seen as “completely unacceptable” to US allies in Europe, said Samantha Gross, director of energy security at Brookings Institution.

“All eyes are on the US plan – it will be crucial to American climate diplomacy,” said Rachel Kyte, an expert in international relations at Tufts University and a UN adviser.

“If it is robust and they can walk the talk and actually implement policies, that will help build momentum. Time is our enemy, it is the one resource we don’t have. There is so much catching up to do from the last four years and we really need to gather speed.”

Joanna Lewis, a specialist in Chinese energy policy at Georgetown University, said the US-China climate commitment was an “encouraging step”, including language that suggests China could make make deeper emissions cuts than previously promised.

“It’s important that Biden puts an ambitious target on the table but it’s equally important that he implements legislation to meet those targets,” she said. “Barack Obama set goals but wasn’t able to do the meaningful legislation, unlike, for example, the UK.”

Biden also faces pressure at home. Scientists and lawmakers are pressing for specific curbs on methane, a potent greenhouse gas released during oil and gas drilling. Some activists were underwhelmed byBiden proposing just $1.2bn in international climate aid in his first budget. Others are keen for Biden to reinstate a US ban on crude oil exports.

“I am risking my life to stop the reckless destruction of my community,” said Diane Wilson, a shrimper who has been on hunger strike for two weeks to protest the expansion of an oil export terminal in Lavaca Bay, Texas.

“Oil and gas export terminals like the project I am fighting pollute our air, water and climate, only to pad the pockets of fossil fuel CEOs. The Biden administration needs to stop the dredging and stop oil and gas exports.”

Whilethe Biden administration is expected to largely focus on its emissions reduction target during the summit, it has been keen to stress it shares environmentalists’ sense of urgency.

“If America fails to lead the world on addressing the climate crisis, we won’t have much of a world left,” said Blinken.

A White House official said that the summit would “up the ante on climate ambition” and would include sessions on topics ranging from building climate resiliency, clean energy innovation and the role of oceans and forests in the climate crisis.

“In short, America is back and we are rallying the world to join us,” the official said. “This is a decisive decade and people should not mistake the urgency. This is a moment of critical transition and if we don’t get it right and get it right quickly we will exceed the carrying capacity of the climate. The problems are global and the consequences are severe.”