Biden’s Urgent Message on Day 1 of His Climate Summit with World Leaders: ‘We Have to Step Up’

Al Drago-Pool/Getty President Joe Biden delivers remarks from the White House during a virtual climate summit on Thursday.

In remarks delivered on day one of his virtual climate summit, President Joe Biden set an ambitious goal of to cutting greenhouse gases in half by the end of the decade, offering an urgent message to the assembled world leaders and others watching the event:

"We have to step up."

Calling climate change "the existential crisis of our times," the president said the world must try to keep the Earth's temperature to an increase of 1.5 degrees Celsius in order to avoid "more frequent and intense fires, floods, droughts, heat waves and hurricanes tearing through communities, ripping away lives and livelihoods, increasingly dire impacts to our public health."

In a fact sheet, the White House said the 2030 goal would entail a "50-52 percent reduction" in greenhouse gases and would be formalized in a public commitment document known as a "nationally determined contribution," or an NDC.

The document will be signed by every country that's signed to the 2015 Paris Agreement, the landmark climate accord under which countries had pledged to cut greenhouse gas emissions 26 to 28 percent below 2005 levels by 2025.

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During his first year in office, former President Donald Trump announced that the U.S. would cease all participation in the agreement, maintaining it was a deal that was not favorable to the country.

On his first day in office after defeating Trump, Biden signed an executive order recommitting to the climate accord, with the U.S. announcing it had officially rejoined the agreement in February.

Underscoring his contrast with his predecessor, Biden tweeted on Thursday: "This Earth Day, I'm proud to say science is back."

In remarks delivered in the White House briefing room following Biden's speech at the summit, the special presidential envoy for climate, John Kerry, addressed criticism from those who wonder how the U.S. will attempt to reemerge as a leader on climate change given Trump's disdain for the issue.

"In the course of the last month, first question out of people's mouths was, 'What are you guys going to do? You destroyed your credibility, left the Paris Agreement, how can we trust you? What's going to happen in the next four years?' " Kerry acknowledged.

Brendan Smialowski / AFP/ Getty World leaders attending the White House's virtual climate summit

He continued: "Regrettably, without any facts, without any science, without any rationale that would be considered reasonable, the former president ... decided to pull out of the Paris Agreement. We had to restore America's credibility, we had to prove we were serious, and I think that today does that in many ways."

In his Thursday speech, delivered to coincide with Earth Day, Biden said that he wanted to create jobs via a climate change response — a tacit response to skeptics who say economic concerns are more pressing than environmental ones — by building "a critical infrastructure to produce and deploy clean technology."

"I see an opportunity to create millions of good-paying, middle-class, union jobs," Biden said, adding that he envisioned work for people to lay energy-efficient grids, autoworkers to build electric vehicles and electricians to install "500,000 charging stations along our highways."

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Forty world leaders convened for the virtual summit, which the White House announced in a release would represent the 17 nations responsible for approximately 80 percent of global emissions and global GDP as well as others "that are demonstrating strong climate leadership, are especially vulnerable to climate impacts, or are charting innovative pathways to a net-zero economy."

The White House said that the summit will also "highlight examples of how enhanced climate ambition will create good paying jobs, advance innovative technologies, and help vulnerable countries adapt to climate impacts."