Late last week, from London to Paris, from New York City to Los Angeles—and in a reported 139 countries around the world—millions of people marched to call attention to climate change in what was billed as the Global Climate Strike.

It was the third in a worldwide series of climate rallies organized by school students hoping to put pressure on politicians and policy makers to act on climate issues. One young person, Swedish 16-year-old Greta Thunberg, became the face of of the issue in her plea to world leaders to act now on climate change, if not for the present, but certainly for future generations who will inherit a world where rising shorelines, devastating storms, droughts and deadly wildfires will become the norm.

In New York City alone, a reported 1.1 million youth were allowed to skip classes on Sept. 20 after the city announced it would not penalize public school students joining the strikes provided they had parental consent. At home, Downtown LA and Long Beach witnessed tens of thousands of persons marching and speaking to the urgent matter of caring for our planet in a time when political differences on Capitol Hill may discourage meaningful change for the better within the climate debate.

In the United States, demands created by environmental justice organizations include calls for a Green New Deal, the end of global deforestation by 2030, and a commitment to communities most affected by climate change. In New York City, Thunberg addressed the United Nations in an outspoken and controversial approach that, of late, has made her the global face of climate change activism.

She spoke her mind in a most provocative way: “This is all wrong. I shouldn’t be up here. I should be back in school on the other side of the ocean, yet you all come to us young people for hope. How dare you? You have stolen my dreams and my childhood with your empty words.”

Thunberg has since drawn comparisons between herself and Pakistani education activist Malala Yousafzai in relation to the young people around the world who are actively speaking for their generation. The teenagers are often dismissed by their elders for being insolent and too “in your face” in terms of economic and political fallout from their activism.

In February, Thunberg wrote on Facebook that “there is no one ‘behind’ me except for myself. My parents were as far from climate activists as possible before I made them aware of the situation.” Thunberg rose to prominence last year by taking time off from school to demonstrate outside the Swedish Parliament about the lack of action to combat climate change. Inspired by her weekly protest, millions of young activists around the globe this month endeavored to pressure their respective governments to act.

Thunberg backed up her words with action. After sailing to New York City in a zero-carbon emissions vessel, she accused leaders at the United Nations climate summit of mere empty rhetoric on climate change. Her indictments didn’t sit terribly well with President Donald Trump. He has questioned climate science and has challenged every US regulation aimed at combating climate change, most notably by pulling the United States out of the 2015 Paris Agreement aimed at reducing carbon emissions, slowing global rising temperatures, and helping nations deal with the affects of climate change.

Trump would retweet some footage of Thunberg’s speech—some attest in a mocking manner—by saying: “She seems like a very happy young girl looking forward to a bright and wonderful future. So nice to see!” Thunberg responded by changing her Twitter biography to: “A very happy young girl looking forward to a bright and wonderful future” in a nod to what type of natural environment her generation will witness by 2050.

Scientists and climate change activists have pointed to the year 2050 for specific reasons in how Los Angeles County will fare. It is the demarcation point of which most scientists agree that the effects of climate change—extreme weather, rising sea levels, wildfires, and a deepening refugee crisis—will be too dire to counter with any form of mitigation. Here are some findings released by UCLA’s Center for Climate Science:

—At mid-century, average temperatures over land areas are expected to rise by 4.3 degrees, compared with a reference period between 1981-2000;

—Warming is not uniform across the Greater Los Angeles region. Valleys and inland areas are expected to warm the most;

—The number of days hotter than 95 degrees will increase across the region (to a greater extent in the interior compared with coastal areas);

—By 2050, temperature changes may affect up to 70 percent of Los Angeles County, meaning that significant climate change is inevitable;

—At mid-century, elevations below about 6,500 feet can be expected to lose roughly half of their snowfall (compared to the period between 1981-2000), and lower elevations stand to lose about 80 percent of the snowfall recorded between 1981-2000.

This week, the public utility commissions in California, Nevada, Oregon, Washington and Colorado united in the Joint Action Framework on Climate Change Memorandum of Understanding to address climate change. These commissions would agree to collaborate and share best management practices for key principle initiatives, including:

—Regional cooperation to address climate change and to decarbonize;

—Development and use of low-carbon technologies in the energy industry;

—Promotion of cost-effective conservation methods;

—Foster a strong and continued commitment to renewable energy resources;

—To support energy planning processes that recognize the ability of low-carbon resources to provide reliability and cost-effective benefits, and,

—Advancement of regional energy and transmission markets to maximize ratepayer benefits.