'Final warning': Lawmakers, Biden administration sound alarm over UN climate report and urge swift action

"If Senators truly followed the science in this report, we'd have 100 votes for climate action to match the 100 percent certainty that human-caused climate change is destroying our planet," Sen. Ed Markey of Massachusetts said in a statement. "This report must be the final warning to the world that time has run out to save the planet from dangerous and irreversible climate change."

The latest IPCC report finds the world is rapidly running out of time to keep human-caused global warming to 1.5 degrees Celsius. The report lays out different scenarios if world nations decarbonize and collectively limit their warming to 1.5 degrees, compared to what will happen if they don't take action -- leading to global warming of 2 or 3 degrees Celsius. The latter would have catastrophic consequences for the planet, leading to already severe weather events like fires and flooding getting worse.

"Every bit of warming matters, and every bit of avoided warming matters," Dr. Jane Lubchenco, the deputy director for climate and environment at the White House Office of Science and Technology Policy, told CNN. "We have to enhance ambition and tackle the climate crisis like the existential threat that it is."

With global warming currently at 1.1 degrees Celsius, this summer has already set new records for heat and drought in parts of the United States. Some lawmakers said they feared this summer could be tip of the iceberg.

"It's not as if this year we're experiencing is going to be a blip, it's going to be the best-case scenario if we don't make changes," Democratic Sen. Tina Smith of Minnesota told CNN. "Ranchers are liquidating their cattle herds because they can't find hay, part of the [Minnesota] boundary waters is closed off because of fire danger. I think about my grandson; is he even going to know snow in Minnesota?"

Smith and other lawmakers said the new report underscored the need for congressional Democrats to pass a $3.5 trillion budget reconciliation bill including strong climate provisions, including tax credits for renewable energy, and a Clean Electricity Standard.

Many lawmakers believe that passing a robust reconciliation bill is their best hope to achieve President Biden's goal of slashing greenhouse gas emissions by 50 to 52 percent relative to 2005 levels by 2030. Biden has also said he wants to get the United States to net-zero emissions by 2050, and decarbonize the US electricity sector by 2035.

"The world must come together before the ability to limit global warming to 1.5 degrees Celsius is out of reach," said US Climate Envoy John Kerry. "What the world requires now is real action. We can get to the low carbon economy we urgently need, but time is not on our side."

Biden and lawmakers have a series of crucial steps this summer and fall. The bulk of budget reconciliation will likely happen in September and October, teeing up the crucial United Nations Climate Change Conference where the US and other nations will meet to discuss decarbonization commitments.

"All major economies must commit to aggressive climate action during this critical decade," Kerry said. "It's the only way to put us on a credible track to global net zero emissions by midcentury. This is the critical decade for action, and COP26 in Glasgow must be a turning point in this crisis."

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