As world leaders were meeting in Manhattan for a United Nations Climate Action Summit Monday, protesters with the Global Climate Strike this week continued calls for more steps to be taken to fight climate change.

Although President Donald Trump originally was not scheduled to be at the UN summit, he was seen attending the conference Monday for a reported 15 minutes before heading off to a religious event being held in New York, according to CBS News. The president spoke at the summit Tuesday but did not address climate change in his remarks.

The previous Friday, an estimated 4 million people around the world engaged in Climate Strikes, or demonstrations staged to compel political leaders everywhere to take action now, before it is too late.

A reported 2,500 such events were held in cities in 150 countries, according to USA Today. In Germany, 270,000 people rallied in Berlin. In England, 100,000 people turned out in London, and 100,000 rallied in Melbourne, Australia, USA Today reported, adding the event was the biggest climate change protest in history. In the United States, organizers in New York City claimed more than 250,000 people attended demonstrations there, while 40,000 people rallied for action in San Francisco.

In New York, 16-year-old Swedish activist Greta Thunberg, whose indignant Friday strikes away from school outside the Swedish Parliament morphed into the global FridaysForFuture movement that ultimately resulted in Friday’s action, electrified listeners during the demonstrations. On Monday, the Los Angeles Times reported Thunberg told UN leaders: “If you choose to fail us, I say we will never forgive you.”

Organizers estimated between 5,000 and 8,000 people attended a rally held in Pershing Square in downtown Los Angeles on Friday. Thousands of people across Southern California also demonstrated for government action against climate change in such cities as Santa Monica, Malibu, Long Beach, Anaheim, Tustin, Irvine, Huntington Beach, Laguna Beach, Claremont and Pasadena.

In Pasadena, local students from Sequoyah School, Caltech and elsewhere led an 11-minute “die-in” on the steps of Pasadena City Hall at 8:50 Friday morning; the 11 minutes represented the approximately 11 years the scientific community estimates the world has left to stave off the climate crisis’ most catastrophic effects.

Press photographers snapped photos as students, activists, parents and teachers stretched out on the pavement, some holding signs aloft: “Fossil Fools.” “Unite Behind the Science.” “System Change Not Climate Change.” “97% of Science Says It’s Imminent.” “If You Keep the Climate Cool We Will Go Back to School.” “Defend the Sacred.” “Adults: Act Like It!” A standard-sized poodle wearing a mobility service dog patch on her harness stood guard beside her owner on the ground. One elderly woman carried a sign reading, “Grandma Says Go Green.”

Students from the Sequoyah School in West Pasadena walked from their campus to Pasadena City Hall after attending a series of workshops on the environment and participated in the rally. 

“This is only the beginning of the movement to treat climate change as the crisis it is and combat it in every way we can,” said Ozzy Simpson, co-president of Sequoyah’s student council.

Throughout the crowd, students of varying ages could also be heard discussing past protests and relevant issues like carbon footprints and methane gas emissions.

Passing cars honked in support as climate strikers marched to Paseo Colorado and along Colorado Boulevard before circling back to Garfield Avenue. A tambourine could be heard accompanying handclaps as people chanted: “No more coal, no more oil, keep your carbon in the soil,” “We are the future, the mighty, mighty future” and “What does democracy look like? This is what democracy looks like.”

Reassembled back at City Hall, an “open mic” session ensued where people were encouraged to speak up. One person said they were there because they were afraid, but another woman called out, “I am not afraid. I am angry!” Others took turns making statements about keeping oil in the ground, holding the wealthy accountable (“100 companies are responsible for 70 percent of the world’s climate emissions”), reducing single-use plastics, and listening to science. When students had finished speaking, climate scientist Peter Kalmus reminded attendees that “one billion activists” are needed to save the planet, its coral reefs, forests and animals, and urged everyone to use their voices and votes to educate their community and “elect good people to Congress.”

Like the die-in at City Hall, many of the demonstrations around the country were attended by young people hoping to be heard as the climate crisis nears an irreversible point.

Another round of rallies is scheduled for this Friday, Sept. 28, the 57th anniversary of the publication of “Silent Spring,” a book written by Rachel Carson which is widely credited with starting the modern environmental movement.

At Monday’s UN meeting in New York, more than 60 world leaders attended the summit aimed at reinvigorating the Paris agreement on climate change, at a time when mankind is releasing more greenhouse gases into the atmosphere.

Trump pulled the US out of the Paris agreement in June 2017.

“I recently left my pickup truck to go to a fully electric car,” said Pasadena Councilman Tyron Hampton, who spoke to students and others attending Friday’s event at City Hall.

“It’s important the city does all it can and we do all we can to protect the environment,” Hampton said.