GEOFF BENNETT: Scientists project that sea levels around parts of Florida could rise as much as eight feet over the coming decades.

The majority of Miami-Dade County is roughly six feet above the ocean today.

And one local artist is doing what he can to sound the alarm.

Jeffrey Brown reports from Miami for our ongoing coverage of the intersection of art and climate change and our series Canvas.

XAVIER CORTADA, Artist and Activist: You're at 10 feet.

You're at five feet.

You're at eight feet.

You are at four feet.

JEFFREY BROWN: At a community event in northern Miami, artist and climate activist Xavier Cortada is reminding residents just how vulnerable their homes are.

Each number represents how many feet of property sits above sea level.

The idea, says Cortada, to make people aware and get them talking in a city where sea level rise is becoming an existential crisis.

XAVIER CORTADA: It calls out the problem.

It literally creates this process where neighbor tells neighbor, these are the facts.

This is the quantifiable problem that we have.

JEFFREY BROWN: His Underwater project starts with a visit to this Web site where participants enter their address and discover their home's elevation.

After writing that number on a sign designed by Cortada, residents place them in their own front yards.

XAVIER CORTADA: That's what my art is about.

You invite your neighbor to get in a conversation with you about that.

And together you begin to figure out what you can do about it.

And enough of that happens, I think we can begin to move the needle on this.

JEFFREY BROWN: Cortada grew up in Miami, the child of Cuban refugees.

His interest in art began at a young age watching his father and uncle paint.

As a law student in the 1990s, he became involved in addressing a variety of local community problems, including drug abuse and gang activity, and began to see how art can be part of such efforts.

A 2006 fellowship in Antarctica, where he saw a close the impact of climate change, changed his life and his direct commitment to using art as a tool of activism.

By 2022, he'd become the inaugural Miami-Dade artist in residence.

XAVIER CORTADA: I think art plays that role, and I think artists are thought leaders.

I don't think they're decorators.

I don't think they're object makers.

I think they help frame and invite society to see and approach things.

JEFFREY BROWN: A painter, sculptor and University of Miami professor, his objects tell a story of rising seas, as with these concrete elevation sculptures, which he places in public parks across Miami.

Always, he wants to reach people where they are.

JENNIFER POSNER, Climate Resilience Academy: I think that's the kind of area where Xavier's work is really important.

JEFFREY BROWN: Jennifer Posner is director of programs for the University of Miami's Climate Resilience Academy, which supports research and solutions to address climate challenges.

JENNIFER POSNER: He's able to reach communities in a way that brings attention to this and makes them aware of what's coming in an approachable way, in a way that they can kind of connect with.

JEFFREY BROWN: She says art projects like Cortada's are especially important to reach the communities most vulnerable to climate change.

JENNIFER POSNER: The fact is that the communities that are most in need that have been historically the most disadvantaged, overlooked are the ones that are experiencing the challenges of climate change the most acutely.

I think it's one thing when we see maps on the news that say, in 20 years, we're all going to be underwater.

He's been so successful in making these really hyper-local connections for people.

Where do they live?

How high is their elevation?

And what does that mean for them?

XAVIER CORTADA: Our planet is in a little bit of trouble.

JEFFREY BROWN: A critical part of Cortada's work connecting with younger generations, on this day at a summer camp at a school in Miami's North Bay Village.

Here, the message was in the form of a mural.

XAVIER CORTADA: This is the elevation, the feet above sea level of your school.

JEFFREY BROWN: Taking it all in, 18-year-old Ezequiel Salvant and 13-year-old Alyn Diaz.

EZEQUIEL SALVANT, Student: These signs, when you see kids more engaged, the parents will be more engaged as well, and overall just help, like, what's going on in our community.

ALYN DIAZ, Student: Art to me is like a way to express yourself and how you feel And your thoughts.

So I believe that it was a great way to portray that.

JEFFREY BROWN: Cortada well knows the political and other tensions over climate change and possible solutions, but he avoids that framing.

XAVIER CORTADA: Framing this as a partisan issue isn't going to solve the problem.

What I'm trying to do is let your neighbor from another party across the street understand that it's black and white.

It's the elevation of your home.

Science in many ways should be the owner's manual for this planet, that it shouldn't be politicized, because Antarctica doesn't care who you're voting for.

It's still coming.

JEFFREY BROWN: Jennifer Posner, who works with a wide variety of community groups and government officials on climate resiliency efforts, believes artists can make an essential contribution.

JENNIFER POSNER: Artists, as usual, are sort of ahead of the curve in this way.

This is going to be a very helpful entry point for policymaking.

JEFFREY BROWN: And, for Xavier Cortada, it's personal.

XAVIER CORTADA: The son of Cuban refugees who have seen their entire island and governance and nation fall apart and understanding that the only place I have ever called home will not be here within a century.

JEFFREY BROWN: He hopes soon to have thousands of yard signs and several hundred elevation sculptures across Miami-Dade County.

For the "PBS News Hour," I'm Jeffrey Brown in Miami.