The mood is about to shift, the hours grow longer and the already high sense of urgency somehow amps up even more as the United Nations climate summit heads into its final week.
Every sentence, every word – especially those about the future elimination of planet-warming fossil fuels – will matter at the UN conference in oil-built Dubai in the United Arab Emirates.
Professional negotiators who have been working on getting options into shape will turn over their work to senior national officials, many at minister levels, who will have to make the tough political choices.
"We're heading into quite a political process, less access into the negotiating rooms, negotiations will go deep into the night, a number of nights," said David Waskow, international climate initiative director for the World Resources Institute.
The central question of the talks is what to do about the fossil fuels that are causing climate change. Activists, experts and many developing nations say they must be phased out quickly in favor of clean energy alternatives that can avert the worst damage on a warming planet. They accuse big energy companies and oil-rich nations of dragging their feet by supporting a slower and ambiguous "phase down."
Even with the hard work to come, some of those who are about to do it have this sense of optimism, especially because everyone has the day off on Thursday.
"We had a pretty damn good week here in Dubai already. Now, obviously, there are some complicated issues to still resolve. We all know that. Nobody is ducking and nobody is going to pretend about that," U.S. Special Envoy John Kerry said. "The negotiators are basically trying to put together in each section a relevant set of options. And then we ministers will have the fun and pleasure next week of kind of noodling through those options."
Multilateral negotiations - involving in this case nearly 200 parties - are much different and often more difficult than the horse-trading two countries can do in bilateral talks, said veteran diplomat Adnan Amin, the COP28 CEO.
The key document is called Global Stocktake. It's the first of its kind in U.N. climate negotiations, saying how far the world has come from the 2015 Paris agreement - where nations agreed to limit warming to 1.5 degrees Celsius (2.7 degrees Fahrenheit) since preindustrial times - and what it has to do next. A draft came out late Monday and negotiators have been pouring over it. Next, officials like Amin will get "a very clear sense by the end of the week where people stand on the text."
Amin said there's a rhythm to these climate talks.
"You start off very hopeful, euphoric," Amin said. "Things are happening. Then the negotiations get hard and people start spreading rumors and conjecture and a little bit of depression, and then things start to come up again. And the clarity of the negotiation process becomes clearer. Then you have the political engagement, and that's where the real intensity and excitement comes."
This is all going the way it should, even if it seems overwhelming, said German special climate envoy Jennifer Morgan.
"There's now a text with many, many brackets (choices), 30 different groups of options for the global stocktake that now needs to be consolidated so that ministers next week can start getting into each of those topics and finding solutions," Morgan said. "There's this moment when one thinks, oh, my gosh, so many texts, so many brackets. But I think, actually the process is going along as it should."
EU negotiators say the core document is in pretty good shape and are confident the key issues are clearly defined. Options remain open for ministers taking over the negotiations which is not often the case at this stage of these difficult multilateral talks.
They expect a new text with the latest amendments to be issued in the early hours of Friday morning, for talks to begin in earnest on Friday at a ministerial level and for a presidential-led process similar to talks Glasgow or Paris.
EU countries, along with small island countries - often victimized by climate change - and some progressive Latin American countries are aligned on calling for a phase-out of fossil fuels, negotiators said. While there will be strong resistance to this measure, officials are confident references to fossil fuels will appear in the final text for the first time and within a timeline compatible with U.N. science reports.
Representatives for poor nations and climate advocates are putting a lot of pressure on negotiators for the fossil fuel sections.
"The success of COP28 will not depend on speeches from big stages," said Uganda climate activist Vanessa Nakate. "It will depend on leaders calling for a just and equitable phase-out of all fossil fuels without exceptions and distractions."
Wopke Hoekstra, the European Union climate commissioner said the bloc will make a big push on the issue, "giving it our all."
A phase-out "will cost money," Avinash Persaud, climate envoy for Barbados said, asking who'll pay. "I don't understand why they are pushing for it to be global. The United States and Canada are two of the richest countries and largest producers of fossil fuels. Why don't we have a phase-out there? It's the cheapest place to phase-out and will have the biggest impacts."
Kerry said he gets that.
"There has to be fairness in the air here," Kerry said. "You know, we don't want people just coming ... feeling maybe, you know, punched a little bit here."
And it's not just fossil fuel language.
"One way or another, next week is going to be really difficult," said Power Shift Africa policy adviser Amy Gillian-Thorpe. "I think we're leaving the lights on for the second week. And that's really unfortunate that we haven't been able to move forward, particularly on adaptation issues."
Kerry said the sense of urgency will win out.
"I'm not telling you that everybody's going to put kumbaya on the table," Kerry said. "But I am telling you we're going to make our best effort to get the best agreement we can to move as far as we can, as fast as we can, and that's what people in the world want us to do. It's time for adults to behave like adults and get the job done."
