The energy in LA’s Japanese American National Museum was palpable. The Live Ride Share conference was sold out and the room was jam-packed when Hasan Ikhrata kicked things off.

The job ahead: No new freeways

Mr. Ikhrata, the executive director of the Southern California Association of Governments, didn’t shy away from the big issues.

His region, he told us — already home to half the state’s population — anticipates substantial population growth. And his job, he said, is to make sure these additional people can get from point A to point B without ever building a new freeway.

Yes. Everyone was listening.

The era of freeways, which Los Angeles pioneered, is gone, continued Mr. Ikhrata. New freeways are not good for the climate, our health, or the economy. Expanding public transit and building homes close to jobs are two key parts of the solution.

We at ClimatePlan couldn’t agree more.

Ride sharing — a new option

It was an exciting note to start on at this first-ever conference on mobility sharing. Ride-sharing technology, Mr. Ikhrata believes, will be a third part of the solution to the massive challenge that he faces — that we all face — as our state grows and our climate changes.

From the turnout, it was clear that a lot of people agree.

What are mobility sharing and ride-share technology? Examples are services like Sidecar, Carma, and others that enable people to use their phones to carpool. (There is some debate over how much Lyft and Uber qualify as “sharing,” but they’re generally included too.) You could also include the many car-sharing services, such as ZipCar, the non-profit City CarShare, GetAround, and more. And public services like San Francisco’s “SchoolPool” trip-sharing website. And of course the exciting new bike-sharing programs springing up around the country.

All of these create new options for people to get where they need to go with less driving, or without owning a car at all.

Research from UC Berkeley shows that ride-sharing can take many cars off the roads and go a long way toward reducing greenhouse-gas emissions. Ride-sharing may suit Southern California especially well because many trips are too short for transit, but too far to walk.

Covering the last mile

These services can help address the “first-mile last-mile“ problem — how do you get to the station from home, or to your destination from the MetroLink or bus stop?

Good transportation is all about options. Bicycling is of course one great way to do the first and last mile — if the streets are made safe for it. Ride-sharing technology offers a new option, making it cost- and time-efficient for people to get a ride to their destinations. Bike-sharing is also an excellent new option in some cities.

Options for whom?

We shared the excitement about the potential of ride-sharing technology. But what about low-income communities and communities of color?

Research bears out what you might assume — currently, ride-sharing technology is typically used by younger, well-educated, upper-income Caucasians in urban areas. Low-income communities also don’t participate heavily in existing bicycle-sharing programs.

Some ideas came up at the conference to address this. One was reducing parking in new housing developments to create more affordable homes, and offering ride-share programs in these developments.

It was widely acknowledged that the housing-transportation cost burden for low-income communities is one of our biggest challenges.

We need to figure this out, and make ride-sharing available to the people who need it most.

The bottom line

Amanda Eaken from NRDC laid it out — our state has to meet greenhouse-gas reduction targets, and we don’t have a lot of time to do it.

Los Angeles is undertaking the most ambitious transportation improvement effort in the country, investing $40 billion in mass transit infrastructure. But it’s going to take more than bus and rail transit to meet our targets on time. Every option, including shared-use mobility, should be on the table.

David Bragdon, executive director of New York City’s Transit Center, said the world is watching Los Angeles, because as California goes, so goes the nation.

Mr. Ikhrata, we’re here to help.