(CNN) US Special Presidential Envoy for Climate John Kerry said Tuesday there is "something different" happening at the COP26 climate summit taking place in Glasgow, Scotland, pointing to a level of engagement by world leaders and a sense of urgency that he hasn't seen at previous United Nations climate summits.
"There is something bigger, more engaged, more urgent in what is happening here than I have seen in at any other COP, and I believe we are going to come up with record levels of ambition," Kerry told CNN's Christiane Amanpour. The gathering in Glasgow is the 26th annual conference of parties (COP) brought together by the United Nations to address climate change.
Kerry said he believes it is possible to reach the goal that world leaders agreed to at COP21 in 2015 -- also known as the Paris Agreement -- of holding global warming to well below 2 degrees Celsius, and if possible, 1.5 degrees Celsius.
"I believe that if people do what they've laid out as their specific plans, yes," Kerry told Amanpour when asked if he still thought 1.5 degrees Celsius was still an achievable target.
The former secretary of state continued: "Is it hard? You're right, it's damn hard. It's very hard, but it is better to push for that. It's better to make that your target."
The prevailing scientific consensus is that temperatures can rise 1.5 degrees Celsius over pre-industrial levels before the most catastrophic changes -- increasingly devastating fires, floods and droughts -- begin to occur.
But significant questions remain about whether some of the world's largest emitters of greenhouse gases, including China and India, will get on board. Chinese President Xi Jinping is not attending COP26 in person.
Kerry said US President Joe Biden reached out to the Chinese President and had a "very good call" in which both leaders agreed they wanted to meet and "move forward on climate."
He noted that, over the last nine months, countries representing 65% of the world's GDP have committed to working toward the 1.5 degrees Celsius target. But he said it was essential that the remaining 35% also make the pledge.
"We have to bring those other countries to the table. We have to raise ambition," Kerry said. "But developing countries, even some big ones like India, can't do this on their own."
Kerry touted the agreement by more than 100 world leaders to end deforestation by 2030, which was announced on Tuesday at COP26, as well as a new US commitment to conserving global forests. He said there would also be some "big finance announcements" in the coming days that the US has been working on.
Biden announced the plan to conserve global forests earlier on Tuesday, saying that conserving forests and other critical ecosystems is "an indispensable piece of keeping our climate goals within reach."
The plan focuses on incentivizing forest and ecosystem conservation and forest landscape restoration, catalyzing private sector action to conserve critical carbon sinks, building long-term capacity and enhancing accountability and increasing ambition for climate and conservation action, according to the White House.
Ahead of the summit, Kerry and Biden climate adviser Gina McCarthy released a five-prong plan for the US to combat climate change: achieve Biden's goal of 100% clean electricity by 2035, transition American cars to electricity, buildings and industries away from burning fuel and toward electricity, help Americans transition to energy-efficient appliances and homes, reduce methane emissions with new rules and invest in carbon removal.