Leaders from nearly 200 nations convened in Belém, Brazil, for the United Nations' COP30 climate summit to address escalating global warming challenges.
The absence of high-level officials from the top three greenhouse gas emitters — China, the United States, and India — dimmed prospects for major breakthroughs.
While China and India sent senior delegations, the Trump administration opted out entirely, with President Trump having dismissed human-caused climate change as "a hoax."
California Governor Gavin Newsom and New Mexico Governor Michelle Lujan Grisham attended to highlight state-level U.S. climate initiatives.
At events in São Paulo and Belém, Newsom lambasted the federal withdrawal, questioning tariffs on Brazil and warning that U.S. inaction cedes clean energy markets to China.
"China is flooding the zone and will dominate in the next great global industry," Newsom said.
He positioned California, with its economy ranking fourth globally and seven times more renewable energy jobs than fossil fuel ones, as a reliable partner in green technology.
Newsom emphasized bipartisan historical actions by California Republican presidents and asserted the state's commitment to compete despite national policy reversals.
A decade after the Paris Agreement aimed to limit warming to 1.5°C, current national plans project a 2.5°C rise this century, with 2024 marking the hottest year on record.
U.N. officials noted emissions are bending downward for the first time, projecting a 12% drop by 2035 from 2019 levels if commitments hold, though far short of the 60% needed.
Delegates anticipate updated pledges, a $125 billion Brazil-led rainforest fund, scrutiny on fossil fuels, and increased pressure for wealthy nations to finance developing countries' adaptations.
Expectations remain low for sweeping agreements amid scarce data on prior finance deliveries.