KING GEORGE ISLAND, Antarctica — Ahead of international climate talks, U.N. Secretary-General Antonio Guterres visited globally-important Antarctica, where ice that’s been frozen for millions of years is melting due to human-caused global warming, to send the message that “we absolutely need to act immediately.”

“What happens in Antarctica doesn’t stay in Antarctica,” Guterres said. In addition to reflecting lots of sunlight away from the Earth, Antarctica regulates the planet’s climate because its ice and cold waters drive major ocean currents. When massive amounts of ice melt, it raises sea levels and changes things like salinity and the habitats of ocean animals.

At the annual Conference of the Parties, known as COP, nations are supposed to strengthen commitments to addressing climate change. But so far these have not been nearly enough to slow global warming, caused by greenhouse gas emissions that result from the burning of fossil fuels.

Guterres is on a three-day official visit to the southern continent. Chilean President Gabriel Boric joined him for an official visit to Chile’s Eduardo Frei Air Force Base on King George Island. Scientists and members of the Chilean military gathered with Guterres aboard a ship where they viewed glaciers and sea birds, including penguins.

Guterres described COP28 which begins next week in Dubai, as an opportunity for nations to “decide the phase-out of fossil fuels in an adequate time frame” to prevent the world from warming 1.5 degrees Celsius (2.7 degrees Fahrenheit) above pre-industrial temperatures. Scientists consider that an important demarcation to avoid devastating climate extremes for millions of people. But language for such a phase-out has not found its way into the agreements that emerge from these conferences, which have a strong presence and influence of participants from fossil fuel companies and countries.

Guterres said COP28 also gives nations the chance to commit to more renewable energy projects and improve the energy efficiency of existing electrical grids and technologies.

Sultan al-Jaber, the head of the Abu Dhabi National Oil Company, is president-designate of this year’s talks. Guterres said his ties to the sector give him a “bigger responsibility” to encourage the fossil fuel industry to make more clean energy investments.

“He needs to be able to explain to all those that are responsible in the fossil fuel industry, and especially to the oil and gas industry that is making obscene profits all over the world, that this is the moment to use those profits instead of doubling down on fossil fuels,” Guterres said.

Pope Francis will also be the first pontiff to attend the U.N. climate conference. Guterres said he is “very hopeful” the pope’s presence will convey to political leaders that “it is a moral imperative to put climate action as an absolute priority and to do everything that is necessary to move from the suicidal trajectory that we are having today.”