UN Chief warns countries that the 'point of no return' on climate change is fast approaching

UN Secretary-General Antonio Guterres warned Sunday that lawmakers and citizens alike across the world should be wary of climate change's "point of no return."

Guterres also dismissed efforts by governments across the world as "utterly inadequate" in his comments ahead of a two-week international climate conference in Madrid, adding that effects from climate change's rising temperatures are already being felt by humans and other species around the world.

Though nations are equipped with the knowledge and resources to confront the changes, Guterres said that "what is lacking is political will" to tax and limit coal, fossil fuels, and carbon.

"The point of no return is no longer over the horizon," Guterres told reporters. "It is in sight and hurtling toward us."

The COP25 summit, which begins this week, will gather delegates from around 200 countries who signed the 2015 Paris climate accord, which President Donald Trump notably announced the US would be leaving this year.

Though Guterres said some countries had made progress with environmental policy and committing to pledges to stop emitting greenhouse gases by 2050, "we also see clearly that the world's largest emitters are not pulling their weight."

"Without them, our goal is unreachable," Guterres said.

The upcoming climate conference comes after a wave of activism aimed at sparking action from world leaders. Leading the charge is 16-year-old climate advocate Greta Thunberg, who sailed to New York City from Sweden on a zero-emissions sailboat to attend the UN's first-ever Climate Action Summit in September.

Around the time of her visit, children and teens in countries across the world skipped school to stage public demonstrations in massive climate strikes.

Thunberg made headlines for delivering an impassioned speech to the General Assembly in which she admonished world leaders for inaction and "empty words" on climate policy.

"This is all wrong. I shouldn't be standing here. I should be back in school on the other side of the ocean," she said with tears in her eyes. "Yet you all come to me for hope? How dare you. You have stolen my dreams and my childhood with your empty words."

Thunberg echoed Guterres' stern warning about the consequences of climate change that are being felt across the world.

"People are dying. Entire ecosystems are collapsing," Thunberg said.