The 2019 Climate Change conference (COP25) is underway, as more than 50 world leaders arrived in Madrid to thrash out policy agreements under mounting public pressure to combat the climate crisis. 

This year's UN Climate Summit comes as a surge in the tangible effects of global warming – extreme flooding in North Western Europe, devastating wildfires in the Americas, and the fallout of hurricanes in the Tropics – have provoked a worldwide youth movement, one demanding that politicians take urgent action against global warming before it's too late.

UN secretary-general Antonio Guterres warned participants during the opening ceremony at Madrid's IFEMA convention centre that the lack of concrete action on climate change risked "sleepwalking past the point of no return."

"Do we really want to be remembered as the generation that buried its head in the sand, that fiddled while the planet burned?" Guterres asked, urging delegates to come to an agreement on unresolved issues from the Paris Agreements, particularly legislation around carbon trading. 

Michał Kurtyka, Poland's climate minister, who led last year's conference in the Polish city of Katowice, stressed the importance of answering the calls of young people to fight the climate crisis:

"They have the courage to speak up and remind us that we inherited this planet from our parents, and we need to hand it over to the future generations."

The new EU Council President, former Belgian Prime Minister Charles Michel, who took over from his predecessor Donald Tusk this weekend, stated: "Now we need to dramatically change how we do things and revolutionize our approach. We have had the Industrial Revolution, the technological revolution, now it's time for the Green Revolution. "

The conference was the first port of call for the new head of the European Commission, Ursula von der Leyen, who took the role over from former EC president Jean-Claude Juncker.

The former German defense minister pledged to reduce the EU's carbon emissions by at least 50% by 2030 during her inaugural speech on Sunday, repeating her plan to make Europe the first climate-neutral continent by 2050.

"In 10 days, the European Commission will present the EU Green Deal. Our goal is to be the 1st climate-neutral continent by 2050. If we want to achieve that goal, we have to act and implement our policies now. Because we know that this transition needs a generational change," she stated on Twitter.

COP25 is the last UN Climate Summit ahead of 2020, when a large number of countries will have to submit new climate action plans, with delegates hoping to use the two-week conference to bring some energy to the debate and get past their policy differences.

However, some of that momentum has been damaged by the decision of US President Donald Trump to formally pull out of the Paris accords. 

In a separate forum, US Congressional leader Nancy Pelosi, who was representing the United States due to Trump's absence from the conference, told delegates that the world could still count on the United States:

"We're here to say to all of you, on behalf of the House of Representatives and the Congress of the United States, we're still in it, we're still in it."

For two weeks, the world's climate change experts come together under one roof for COP25.

Every day, CGTN will be asking one of them what they would do to stop global warming.