Katowice, Poland (CNN) The heads of state for some of the main countries causing climate change -- the United States, the UK, Germany, China, Canada and India among them -- are not present here in Poland to try to keep the wheels from falling off an agreement meant to save humanity and the planet.

So the weight of the world at the COP24 climate talks here in Poland appears to be falling on tiny nations like Vanuatu, which saw more than half of its GDP vanish after a recent cyclone.

That nation's minister of foreign affairs, Ralph Regenvanu -- call him "Minister Ralph," his delegation says -- has emerged as one of the few clear, moral voices present at these talks, which are seen by some scientists, environmentalists and policy experts as a "huge mess" that threaten to cause calamity if they fall apart entirely this week. The UN Secretary-General António Guterres on Wednesday said it would be "suicidal" for these global warming negotiations to fail.

Regenvanu stood at a lectern wearing a green tie and glasses, indicting the global community.

"[P]arty negotiators rocking meaningful progress should have much on their conscience," he told diplomats on Tuesday. "There is no political argument to counter atmospheric measurements showing that CO2 emissions have risen since Paris and are on track for a 2.7% rise in 2018," he said, referencing the 2015 UN climate negotiations in Paris -- a moment when the world stood in unison demanding an end to fossil fuels. "Whether you 'welcome' or 'note' or shamelessly ignore the science all together, the fact remains that this is catastrophic for humanity."

In the guarded world of climate diplomacy, Regenvanu's statement is a massive burn to the United States, Russia, Saudi Arabia and Kuwait. Over the weekend, those nations refused to "welcome" the latest scientific report from the Intergovernmental Panel on Climate Change, which makes clear urgent action is needed to avoid catastrophe, including superstorms, deadlier heatwaves and floods. Those countries instead asked to simply "note" the report's existence. The United States issued a statement questioning the well-established science. As did Saudi Arabia.

"The time for limitless negotiations on climate change has passed," Regenvanu said. "It pains me deeply to have watched the people of the United States and other developed countries across the globe suffering the devastating impacts of climate induced tragedies while their professional negotiators are here at COP24 putting red lines through any mention of loss and damage in the Paris Guidelines," he added, "and square brackets around any possibility for truthfully and accurately reporting progress against humanity's most existential threat."

A US State Department spokesman did not respond to a request for comment on that critique.

Important aspects of the talks, which aim to create rules for tracking carbon emissions cuts as part of the Paris Agreement, which was hashed out three years ago, have become "a huge mess," said Bill Hare, director of Climate Analytics, a research group based in the UK.

"What we're seeing now is that many countries are exploring the bottom of the drain when it comes to ambition -- and in a surprising way," said Hare, who is a climate scientist and physicist. "For those in the scientific community following this here, the levels of concern are rising." The rules as they were being discussed early Wednesday would allow for "massive loopholes" and "double counting" that would create confusion about how much countries really were doing to curb greenhouse gas emissions that warm the planet, he said. It's so bad that he's started to wonder if it might be better for countries not to agree on anything at all -- rather than to codify lasting rules that are weak to the point of irrelevance.

Hare's teenage kids have been asking him if the whole process is, in fact, irrelevant.

"If at that moment we can't see progress then people can legitimately ask what is going on with this," Hare said. "What exactly is this (Paris) Agreement doing -- and how can it be fixed? Right now, I think concern is rising but the moment of truth is not quite there yet."

The final test, Hare said, will be 2020, when countries submit updated pollution-reduction plans.

Jeff Sachs, director of the Center for Sustainable Development at Columbia University, said the discord is a sign that "this process is not working." "Leading countries -- especially the United States -- are fighting hard against," the Paris rulebook, he said. "These meetings go on and on. It's very sad ... There are not more than a handful of countries that are going to determine the fate of the world."

Jennifer Morgan, executive director of Greenpeace International, said a severe lack of leadership at the UN COP24 talks is resulting in mass confusion at this "critical" stage. It's like the talks inside this sterile conference center are on another planet from the real world, she said, where wildfires, storms and other climate calamities are becoming more severe, where the science of climate change never has been starker, and where people are demanding action.

"There is a way forward, but it requires leadership," she said. "That's the gap -- the leadership."

Instead, said Eliza Northrop, a senior associate at the World Resources Institute, there's "bickering" about basic science showing more than 1.5 degrees of warming would be disastrous. People already have warmed the climate 1 degree since the Industrial Revolution.

COP24 talks are being held in Katowice, Poland, which is the heart of European coal country. Poland has the reputation for being a laggard in climate negotiations and some observers say the country's leadership at the talks has been lacking, perhaps related to those interests.

The COP President, Michał Kurtyka, from Poland, told delegates late Tuesday that there had been "insufficient progress" at the talks. That was bold considering the sensitivities, said Jake Schmidt, who directs the international program at the Natural Resources Defense Council. Schmidt said no one is expecting wild success from COP24 -- they best to hope for is a "B" grade, he said. It's worrying that these rules don't often get stronger as negotiations trod on, he said. "It's rare that the thing gets better. It does sometimes. Paris was a rare exception," he said. "It's pretty rare to start with a low bar and work your way up at this stage ..."

Delegations from rich countries with some moral high-ground -- Germany, New Zealand and Canada, among them -- are not doing enough to rally support, observers said. The United States used to fill that role as a sheep herder, said Hare, but is noticeably absent here. US President Donald Trump's administration promotes increased coal extraction and questions the basics of climate change, despite longstanding scientific consensus that burning coal, oil and natural gas for electricity and other purposes dangerously warms the atmosphere. The US delegation drew protests here this week at an event promoting fossil fuels and technology.

The negotiations are expected to continue through Friday or likely beyond.

"The window of opportunity is closing," said UN Secretary-General Guterres. "We no longer have the luxury of time. That's why we need to have the work of Katowice finalized -- and finalized in three days."

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"Minister Ralph" is willing to hold onto whatever hope he can grasp.

The nations of the world are more linked together than ever by this common enemy, he said in an interview.

And this is a problem too significant to give up.

"We live on one planet," he said. "We're all affected by the same climate.

"We hope there will be some compromise."