For 30 years, world leaders and diplomats have gathered at United Nations negotiating sessions to try to curb climate change, but Earth's temperature continues to rise and extreme weather worsens.

So this month, they're hoping for fewer promises and more action.

Past pledges from nearly 200 nations have fallen far short, and new plans submitted this year barely speed up pollution-fighting efforts, experts say.

And if the numbers aren't sobering enough for world leaders when they kick off the action Thursday, there's the setting: Belém, a relatively poor city on the edge of a weakened Amazon.

Unlike past climate negotiations — and especially the one 10 years ago that forged the landmark Paris climate agreement — this annual U.N. conference isn't primarily aimed at producing a grand deal or statement over its two weeks.

Organizers and analysts frame this Conference of Parties — known less formally as COP30 — as the “implementation COP.”

What's needed now is more money and political will for countries to put decades of words and promises into action and policy to reduce heat-trapping gases and stop deforestation.

Only that will put the brakes on global warming as it careens toward a level the world has agreed is too dangerous, according to experts interviewed by the Associated Press.

In Belém, diplomats, activists, scientists, and business leaders will discuss new national climate-fighting plans, the need to save trees that absorb carbon pollution, how communities can adapt to warming, and how to financially help developing nations hit hardest by climate change.

Host Brazil will preside and set the agenda.

Those leaders arrive Thursday for a two-day pre-meeting summit to discuss ratcheting up the fight against climate change.

That high-level meeting is likely to be missing top leaders of the biggest carbon-polluting nations: China, the U.S., and India.

They contribute about 52% of the world's heat-trapping carbon dioxide from the burning of coal, oil, and natural gas.

China is sending its deputy premier.

The U.S. is mostly skipping this conference under President Donald Trump, a climate change skeptic who's begun the process of withdrawing from the Paris agreement.

Some U.S. cities and states are coming to show that they and businesses take climate change seriously, said former U.S. Environmental Protection Agency chief Gina McCarthy, who co-chairs a group called America Is All In.

There's already a divide on the nature of this meeting.

Brazil is stressing implementation of past plans as well as what's in new emissions-cutting plans submitted this year.

But smaller island nations, such as Palau, and scientists are saying that's not enough.

It dooms Earth to 3 degrees Celsius (5.4 degrees Fahrenheit) of warming since pre-industrial times, they said.

Palau and island nations want negotiators to tell countries to be more ambitious in their new carbon pollution-cutting plans.

“The challenge today is not whether we will phase out fossil fuels. The challenge today is will we be too late?” Rockström said. “We are heading towards catastrophic 3 degrees.”

AP video by Lucas Dumphreys

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