But 2024's climate talks are more like the International Chess Federation world championship, lacking the recognizable names but big on nerd power and strategy. The top leaders of the 13 largest carbon dioxide-polluting countries will not appear. Their nations are responsible for more than 70% of 2023's heat-trapping gases.
The world's biggest polluters and strongest economies — China and the United States — aren't sending their No. 1s. India and Indonesia's heads of state are also not in attendance, meaning the four most populous nations with more than 42% of all the world's population aren't having leaders speak.
"It's symptomatic of the lack of political will to act. There's no sense of urgency," said climate scientist Bill Hare, CEO of Climate Analytics. He said this explains "the absolute mess we're finding ourselves in."
The world has witnessed the hottest day, months and year on record "and a master class in climate destruction," United Nations Secretary-General Antonio Guterres told the world leaders who did show up.
But Guterres held out hope, saying, in a veiled reference to Donald Trump's re-election in the United States, that the "clean energy revolution is here. No group, no business, no government can stop it."
United Nations officials said in 2016, when Trump was first elected, there was 180 gigawatts of clean energy and 700,000 electric vehicles in the world. Now there's 600 gigawatts of clean energy and 14 million electric vehicles.
Host Azerbaijan President Ilham Aliyev kicked off two scheduled days of world leaders' speeches by lambasting Armenia, western news media, climate activists and critics who highlighted his country's rich oil and gas history and trade, calling them hypocritical since the United States is the world's biggest oil producer. He said it was "not fair" to call Azerbaijan a "petrostate" because it produces less than 1% of the world's oil and gas.
Oil and gas are "a gift of the God" just like the sun, wind and minerals, Aliyev said. "Countries should not be blamed for having them. And should not be blamed for bringing these resources to the market because the market needs them."
As the host and president of the climate talks, called COP29, Aliyev said his country will push hard for a green transition away from fossil fuels, "but at the same time, we must be realistic."
Aliyev, United Kingdom's prime minister Keir Starmer and Turkey's president Recep Tayyip Erdogan are the headliners of around 50 leaders set to speak on Tuesday.
There'll also be a strong showing from the leaders of some of the world's most climate-vulnerable countries. Several small island nations presidents and over a dozen leaders from countries across Africa are set to speak over the two-day World Leaders' Summit at COP29.
As a sense of how the bar for celebrity has lowered, on Tuesday morning photographers and video cameras ran along side one leader walking through the halls of the meeting. It was the emergency management minister for host country Azerbaijan.
United Nations officials downplayed the lack of head of state star power, saying that every country is represented and active in the climate talks.
One logistical issue is that next week, the leaders of the most powerful countries have to be half a world away in Brazil for the G20 meetings. The United States recent election, Germany's government collapse, natural disasters and personal illnesses also have kept some leaders away.
The major focus of the negotiations is climate finance, which is rich nations trying to help poor countries pay for transitioning their economies away from fossil fuels, coping with climate change's upcoming harms and compensating for damages from weather extremes.
Nations are negotiating over huge amounts of money, anywhere from $100 billion a year to $1.3 trillion a year. That money "is not charity, it's an investment," Guterres said.
"Developing countries must not leave Baku empty-handed," Guterres said. "A deal is a must."