John Kerry, U.S. special presidential envoy for climate, speaking at a summit in New York City in September. Source: Riccardo Savi/Getty Images Entertainment via Getty Images

Buoyed by international commitments ahead of COP26 and the promise of technological breakthroughs, top U.S. climate diplomat John Kerry is heading to the Glasgow summit with optimism.

The lead up to the talks, which kick off Oct. 31, has already summoned more climate pledges than ever before, according to Kerry, the former U.S. secretary of state who now serves as U.S. President Joe Biden's special envoy for climate.

"In that regard, Glasgow has already seen success," Kerry said during an Oct. 28 event at the London School of Economics and Political Science.

COP26 will see the U.S. return to the negotiating table after former President Donald Trump removed the country from the Paris Agreement on climate change, through which nations agreed to limit global warming to 2 degrees C and ideally below 1.5 degrees.

"No-one is exaggerating when they call [climate change] an existential threat," Kerry said. "That is what makes this the decade of decision, and now we must make it the decade of action."

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During the years of U.S. disengagement, the U.K., Europe, as well as cities and other stakeholders across the U.S. filled the breach, the climate envoy said, adding that the world owes them a debt of gratitude. Under President Biden, "Every department, every agency, every cabinet official is at the table."

"Paris did pull us back from the brink [and] gave the world a chance to save ourselves," Kerry said. Nationally Determined Contributions from countries laying out their commitments toward delivering on the Paris goals are a "huge improvement of where we had been," and send an important signal to the market, with investments in renewable energy surging, he said.

Indeed, renewables dominate investment in new power generation and are expected to make up 70% of 2021's total of $530 billion spent on fresh capacity, the International Energy Agency said in June.

'Let's get this done'

While some countries have already been able to transform their power systems to rely mainly on renewables, many developing nations face legitimate economic challenges as they seek to transition away from fossil fuels, Kerry said. Consensus on financial support from the developed world is a key agenda item for COP26, with a target of $100 billion.

"What I want to see in Glasgow ... is to get a better understanding of how to deploy that money," Kerry said. Partnerships between developed and emerging economies can be an effective tool for this deployment, he said, drawing on the example of a U.S.-India partnership on rolling out India's renewables fleet. If successful, India can in turn rally others in the developing world and lead by example, he said.

Seeing the promise of green business models, even oil-rich nations such as Saudi Arabia are beginning to pivot their economies toward clean energy, Kerry said, pointing to a green hydrogen project in the country that is aiming to export the fuel into Europe.

"These are not just sketches of the imagination, these are real things people are investing in," the climate envoy said, adding that economies not yet backing the transition will soon feel financially compelled to not miss out.

"The race for the new technologies is going to result in unbelievable numbers of new jobs and a lot of money is going to be made," he said, referring to technologies like batteries, direct air capture and hydrogen.

"Let's get this done, it's doable," Kerry said about the COP26 talks. "I head to Glasgow an optimist."