The internationally renowned naturalist Sir David Attenborough says that climate change is the greatest threat to the world in thousands of years.
Meanwhile, the presidents of at-risk states such as Fiji, Nigeria and Nepal are expected at COP24 talks, which aim to flesh out the promises agreed to in the 2015 Paris climate accord.
"Developed nations led by the USA will want to ignore their historic responsibilities and will say the world has changed", said Meena Ramam, from the Third World Network advocacy group.
Natural historian David Attenborough listens to speeches during the COP24 summit on climate change in Katowice, Poland, on Monday.
"Even as we witness devastating climate impacts causing havoc across the world, we are still not doing enough, nor moving fast enough, to prevent irreversible and catastrophic climate disruption", Mr Guterres said.
COP24 comes on the heels of the G-20 gathering in Argentina, where 19 of the 20 leaders signed a communique reaffirming their commitment to fight global warming, but President Donald Trump insisted on a paragraph outlining his opposition and the USA decision, under his administration, to withdraw from the 2015 Paris agreement.
The Paris deal saw nations agree to limit global temperature rises to below two degrees Celsius and under 1.5C if possible.
Net zero emissions mean that any greenhouse gases emitted need to be soaked up by forest or new technologies that can remove carbon from the atmosphere.
"We have a collective responsibility to invest in averting global climate chaos", he said.
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He said governments should embrace the opportunities rather than cling to fossil fuels such as coal, which are blamed for a significant share of man-made greenhouse gas emissions.
The remark was also directed at host Poland, which relies on coal for 80 per cent of its energy. But Poland's President Andrzej Duda told a later news conference that the coal-rich country will never entirely give up its "strategic fossil fuel".
Guterres also urged negotiators not to forget that the challenges they face pale in comparison to the difficulties climate change already is causing millions of people around the world whose homes and livelihoods are threatened by rising sea levels, drought and more powerful storms.
Guterres went on to say that the world is "nowhere near where it needs to be" on the transition to a low-carbon economy.
Schwarzenegger said he wished he could travel back in time, like the cyborg he played in his film The Terminator, so he could stop fossil fuels from being used.
"Mr Attenborough has been leading a campaign to engage ordinary people with the COP24 conference, leading a campaign called #TakeYourSeats, calling on members of the public to submit comments, questions, pictures and videos, as well as a series of global opinion polls curated in to 'the people's address" shown as part of his presentation.
Delegates from almost 200 countries now have two weeks of negotiations to finalize how those goals work in practice, even as science suggests the pace of climate change is rapidly outstripping mankind's response.