The 92-year-old naturalist addressed the delegates from more than 200 nations in Katowice, as teams work to find ways to ensure implementation of the historic 2016 Paris Climate agreement that seeks to slash global greenhouse emissions from 2020.
Over the weekend, 19 G20 member states reaffirmed their commitment to the Paris climate accord - except for the U.S., which pulled out of the landmark agreement a year ago.
This is response to the Talanoa Dialogue, which was launched at COP23 in Bonn in 2017, with the aim of raising conversation in which countries would check the progress and seek to increase global ambition to meet the goals of the Paris Climate Change Agreement.
Hosting the talks in the heart of its coal region of Silesia, Poland tried to set the tone for the two-week meeting by promoting the idea of a "just transition" for miners and other workers facing layoffs as countries adopt alternative energy sources.
But the Paris agreement let countries set their own emissions targets.
Addressing the event, World Bank President Jim Yong Kim highlighted the plight of the world's smallest and financially weak countries in the face of climate change, saying that they will bear the brunt of the impacts from climate change, CNN reported.
Belgian police said some 65,000 people participated in Sunday's "Claim The Climate" demonstration, many of them on their bikes.
To contain warming at 1.5 deg C, man-made global net carbon dioxide (CO2) emissions will need to fall by about 45 per cent by 2030 from 2010 levels and reach "net zero" by mid-century, according to the UN Intergovernmental Panel on Climate Change (IPCC).
"America is more than just Washington or one leader", he said, calling Trump "meshugge" - Yiddish for "crazy" - for deciding to withdraw from the Paris accord.
Officials from almost 200 countries now have two weeks to finalize how those goals work in practice, even as science suggests the pace of climate change is rapidly outstripping mankind's response. "They are behind you, along with civil society [who are] represented here today, supporting you in making tough decisions, but also willing to make sacrifices in their daily lives", he added.
Meanwhile, on the occasion of the 24th Conference of the Parties (COP24), the German Embassy in Dhaka organised a "climate breakfast" on Monday.
But Katowice comes ahead of an end-of-year-deadline for the United Nations to agree on a "rule book" for enforcing action on climate change.
And researchers have also found that climate change is contributing to the destruction of some of the world's most vulnerable natural habitats and is compounding natural disasters, like hurricanes, by increasing rainfall.
Delegates said that one of the trickiest issues could be monitoring emissions as the United States, which cannot quit the pact until 2020, uses the talks to press for a level of detail it perceives as useful to its foreign policy dealings. 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 urged developed nations to deliver on this commitment, while urging Member States "to swiftly implement the replenishment of the Green Climate Fund".