AUSTIN, Texas -- Austin's mayor and hundreds of other leaders nationwide are sending a message, 'We are still in,' after President Donald Trump withdrew the United States last week from the Paris Climate Accord.

After the President's announcement, leaders joined an open letter showing their support for the agreement. Among the signatures are those of Austin Mayor Steve Adler and Dallas Mayor Mike Rawlings. Houston and San Antonio leaders had not signed the letter as of Monday evening.

"The dangers associated with climate change are real," Adler said.

Pedro DiNezio, Ph.D., is a climate scientist at UT Austin's Institute for Geophysics. He said even small steps move us all forward.

"Transportation uses so much energy and fossil fuels," DiNezio said. "Driving less is the easiest, fastest way to reduce our carbon footprint."

If you live near a bus or rail route route, DiNezio encourages you to take it since it's probably going where you want to, anyway. Second to transportation, he said food is a major contributor to a person's carbon footprint.

"Transitioning to chicken and just eating chicken will reduce your carbon footprint a lot because beef is the problematic meat," he said.

Mayor Adler said the city's already reducing its impact by adding electric cars to the fleet as it can. Additionally, leaders are ensuring government buildings are self-sufficient from an energy standpoint.

"We have set some pretty ambitious goals for the city operations to have a zero carbon footprint in just a few years--for the whole community to have a zero carbon footprint by the year 2050," Adler said.

While the region's the fastest growing in the country between 2010 and 2016, it also lost a considerable amount of density. In fact, of all the largest metro areas, Austin was only second in sprawl to San Antonio.

That means people drive further, and they leave a larger carbon footprint in their wake. Adler's hopeful a rewrite of the city's land development code, known as CodeNEXT, will reverse that trend.

"The more we are able to set up how and where we live in a way that helps our transit fill buses and increase ridership helps with the climate change challenge," Adler said.

The city's biggest single polluter is the Fayette Power Project. It co-owns the coal-fired plant along with the Lower Colorado River Authority. Mayor Adler said Austin Energy still uses the power plant to provide energy to the state's electric grid, but the city is already setting aside funds to decommission the plant within the next decade.

"The cost that we are seeing associated with running a coal plant, the LCRA is seeing as well, so the same economic pressures would be on them," he said.

Along with striving for a net zero carbon footprint by 2050, the city hopes to be zero waste by 2040. That means Austin residents and businesses will recycle 90 percent of what they discard.

Full of cities still following Paris Accord: We Are Still In.com