JOHN YANG: Just as television supplanted AM radio for drama, comedy and variety shows in the 1950s and FM radio became the medium of choice for music by the 1980s, streaming internet and podcasts have been challenging AM radio for listeners.

Now there's another threat.

Car makers are installing radios without the AM band as standard equipment on electric vehicles citing interference from electric motors on AM radios.

Critics say limiting AM radio's reach will have repercussions for politics and public safety.

Katie Thornton is a freelance journalist who researches all things radio and hosted the award winning podcast the Divided Dial.

Katie, what is left on AM radio these days?

KATIE THORNTON, Host, The Divided Dial: Yeah, as a lot of people might think of Am radio, there is a lot of talk and specifically a lot of conservative talk that's sort of, I think, what a lot of people know AM radio best for.

But what a lot of people might not know about AM radio is that it also is home to a lot of the country's sort of increasingly rare locally owned stations and it's home to a lot of non-English language broadcasts as well.

And so there's really a diversity of programming and a diversity of voices on AM that is sort of unmatched on the FM band.

JOHN YANG: There are some Republicans who say it's a plot against the conservative talk shows, but there are Democrats as well.

There's a bipartisan coalition in Congress who want to build to require AM radios in cars.

And one of the things they cite is public safety, the emergency services announcements on radio.

KATIE THORNTON: Yeah, certainly public safety is a huge part of AM radio for a lot of folks who may not have reliable cell service, may not have reliable internet access.

AM radio is still a really crucial way of getting public safety information, getting weather information, getting traffic information.

But even in times that aren't emergencies, AM radio still does play a really crucial role for a lot of folks.

I mean, specifically in rural areas, the way that the technology works, it doesn't have very good audio quality, so it's not the best for music, but it can cover really long distances and it can penetrate buildings and mountains in a way that FM just can't.

So it serves a crucial role for public safety, but also for sort of civic engagement in rural areas in particular and also in urban areas there are a number of non-English language programs that are on AMA radio.

You know, AM radio stations serve a crucial need and really provide a fill a void for in terms of diversity in our media ecosystem in rural areas and in cities alike.

JOHN YANG: Do we know what listenership is for AM radio now and how it compares to previous years?

KATIE THORNTON: Yeah, you know, I think a lot of people talk about radio generally and AM radio in particular as being sort of a dying medium.

And I think that's a really big oversimplification.

A lot of people are still listening to the radio generally.

Over 80 percent of Americans listen every week.

And it's still about neck and neck with social media for how Americans get their news.

But within that 80 percent of Americans that are listening to the radio every week, only about 20 percent of those listeners are saying that they're listening specifically to AM.

So it's certainly a smaller audience.

And it is an audience that is aging, that is getting smaller, but it's still a really large portion of the American public and it still has a lot of importance and a lot of influence.

JOHN YANG: The rise of electric vehicles that only have FM bands that have no AM bands on them.

How big a threat is that?

KATIE THORNTON: Yeah, that's a really good question.

I think it's sort of hard to parse.

There's a lot of sort of uproar right now about the fact that a lot of automakers are taking these AM radios out of electric vehicles because of electric interference.

It's even noisier even buzzier than the AM band normally is because electric drivetrain components sort of operate at a similar wavelength to AM radios.

But I think that if you ask some folks in the AM radio world, they don't necessarily see that as an existential threat to AM radio.

A lot of the places where AM radio is most vital are not necessarily places where there's currently infrastructure for electric vehicles.

And I think really since the inception of broadcast, you know, popular broadcast radio, there have been sort of rumors of its death, rumors of the death of radio for almost 100 years now.

People said that commercials on the radio were going to kill radio.

People said FM would kill AM.

TV would kill AM.

The internet would.

These are still, you know, they give AM a run for their money.

But AM really holds its own.

It's still really influential.

And so while I don't think that electric vehicles are going to be the nail in the coffin of AM radio, it is certainly a hurdle.

And it's something that I think is getting a lot of people thinking about what the future might look like for those stations that find a home on the AM band and for the listeners who rely on it.

JOHN YANG: Writer Katie Thornton on AM radio.

Thank you very much.

KATIE THORNTON: Thank you.