Argentinian muralist Andres Iglesias, who works under the pseudonym Cobre, is about a week away from completing the enormous artwork on the side of a building in the city's central Union Square neighbourhood.
"The second step is to get angry and get active", she said of lobbying government, business and others in power to stop talking about climate change and actually do something about it.
Greta Thunberg, the 16-year-old Swedish climate activist, brought her message to North Carolina Friday - just a few days after the USA announced its plans to formally withdraw from the Paris Climate Agreement. He painted the Robin Williams mural on Market Street that has recently been demolished to make way for some high rise apartments.
As Cobre tells KPIX, "What I want from people is to realize have to do something for the world".
Cobre tells TIME that the project of Thunberg's mural began about a year ago when environmental non-profit One Atmosphere approached him after seeing the mural of Williams.
One Atmosphere is understood to be supplying all the paint and materials for the Thunberg project. Earlier this year, the UK-based aerosol artist Jody Thomas painted a 50ft portrait of the teenager on the face of the historic Tobacco Factory in Bristol.
The Trump administration announced earlier this week that the USA would officially leave the Paris Climate accord on November 4, 2020, which is the day after the 2020 election.
Her fiery speech at the United Nations inspired millions while getting mocked by those of us who recognize it for what it is: hysteria.
"You have stolen my dreams and my childhood with your empty words".
"There's something about that girl that gives me the creeps.That mural and those eyes is something straight out of a dystopian SciFy movie", one wrote, commenting on the SFist story.
"It can be hard in times like these to find hope, I can tell you", Thunberg said before the interruption. Entire ecosystems are collapsing.
"My message is that we'll be watching you", said the teen activist, whose mural will now keep watch over San Francisco, acknowledged as a city embracing environmental mindfulness.