NEW YORK (CBSNewYork/AP) -- Scientists took to the streets in New York and around the world Saturday in defense of scientific work from attacks including U.S. government budget cuts.
The March for Science began with a rally at 10:30 a.m. near Columbus Circle at Central Park West.
Thousands of participants then walked Broadway to 52nd Street.
"Everything from environmental and climate justice, to justice for people living day to day with clean water," one marcher said.
"We want to get across the message that Americans really care about science, and we care about this world, and that we really need science to help us thrive," scientist Dawn Cohen said.
Scientists and their supporters say they're worried about political involvement in science that rejects, for instance, climate change and the safety of vaccines. Activists say the immigration policies of the Trump administration could keep some foreign scientists from working in the United States.
"The message is that we don't care about your politics. We care about the planet," a marcher told WCBS 880's John Metaxas. "The planet needs people to pay attention to it. It's calling us. It's crying."
Marchers held signs with such slogans as, "The oceans are rising and so are we," and, "Denial is not a policy."
Some marchers also held signs with a silhouette of President Donald Trump and messages such as "absolute zero" and "black hole."
"It says Trump makes me a mad scientist and I'm carrying it, because I'm mad that the government is defunding a lot of science projects that are very important to saving the planet," a marcher said.
A small crowd of about 200 also gathered in Foley Square, 1010 WINS' Andrew Falzon reported. Julie from Mamaroneck made the trek for her voice to be heard.
"Climate change; I'm against Trump's assault on animals. He's repealed the ban against Alaskan wildlife, so now he's opened up hunting on refuges," Julie said.
The events in the city drew large crowds and caused gridlock through Midtown. But a woman named Matilda said it was worth the inconvenience.
"We have a wonderful civilization that we built, but we built also a lot of destructive things, and we have to stop that once we see the harm it does," she said.
A crowd estimate for the march was not immediately available.
Marches for science were also held in other cities around the country and world. In Chicago, a huge crowd gathered in Grant Park and marched to the Field Museum of Natural History, where more than 50 science-related non-profits and research groups were set up for a three-hour expo.
Meanwhile this Earth Day, cars have been banned on a 1.6-mile stretch of Broadway. Car Free Day means a ban on motor vehicles on Broadway between Union Square and Times Square beginning at 10 a.m. Saturday and continuing until 4 p.m.
Thirty blocks of Broadway were shut down to traffic for the second annual Car Free NYC, making room for bikes, aerobics, and even Parkour, CBS2's Ali Bauman reported.
"The city is filled with opportunities to grow, and move and play," Jesse Danger, who was partaking in Parkour, said.
"You don't have to worry about cars all around, and trying to fight the lanes with the cars," bike rider Evan Chang said.
"Mainly we want New Yorkers to get out and have a fun day. But our message today is also an environmental message, it is Earth Day. And just to talk about reminding people what we should be all doing together to reduce emissions, to combat climate change," city Transportation Commissioner Polly Trottenberg said.
Pedestrians will have the run of traffic-cleared streets, where they can catch an outdoor performance or go on a walking tour.
"This is a day when we imagine a city where people are walking and biking and people have good alternatives to get out of their car," Trottenberg told WCBS 880's Myles Miller.
In Washington Heights, no cars were allowed on St. Nicholas Avenue between 181st and 190th streets.
"It's a celebration of the respect that we have to give to mother Earth," said City Councilman Ydanis Rodriguez (D-10th). "But it's also inviting the private and public sector to do better when it comes to improving several services in our buses, in our trains."
Rodriguez, who chairs the City Council Transportation Committee, noted that most New Yorkers do not own cars. He said the only way to make reduce the number of cars on the streets is to make investments in public transportation – especially in transportation deserts like the Bronx and Queens.
"New York should have choices -- especially those who live in transportation deserts – to make a decision of owning a car where they have to invest a lot of money or use public transportation," he said.
Gov. Andrew Cuomo released a statement Saturday honoring Earth Day and noting the challenges facing the environment.
"From combating climate change and reducing carbon emissions to safeguarding our coastal communities and strengthening resiliency in the face of extreme weather -- New York must continue to lead the way forward," Cuomo said in the statement.
Cuomo noted that the state is planning to source 50 percent of its electricity from renewable sources by 2030, and is maintaining record funding for the state Environmental Protection Fund. The state is also advancing solar, wind, and energy efficiency initiatives, Cuomo said.
"And even as the federal government in Washington abdicates its responsibilities, New York is committed to exceeding the targets of the Clean Power Plan and setting a national example for progress," Cuomo said in the statement.
Mayor Bill de Blasio also announced for Earth Day that the NYC Green Job Corps will be launching its first class of pre-apprenticeships. The program – developed in cooperation with the Building Construction Trades Council – will train more than 3,000 workers, according to the Mayor's office.
"This Earth Day, we're making a statement: fighting climate change and creating good-paying jobs go hand-in-hand," de Blasio said in a news release. "The NYC Green Jobs Corps will support the training of 3,000 workers who will be instrumental in making this a cleaner and better city. New Yorkers are working together to help realize our shared vision for a more sustainable, resilient and just city."
State Attorney General Eric Schneiderman also emphasized the need to clean up the earth.
"It is no secret that there are some who are attempting to weaken—and reverse—these important gains that we have made, which would cause untold damage to our air, water and climate," Schneiderman said in the statement. "It is inspiring to see thousands marching across the country today who are fighting for a healthier and cleaner environment, and I stand behind them and will use every tool to ensure that we move forwards, and not backwards, in protecting our planet."
President Trump himself also honored Earth Day in a statement, emphasizing that environmental protection must be balanced with job creation.
"My Administration is committed to keeping our air and water clean, to preserving our forests, lakes and open spaces, and to protecting endangered species," Trump's statement said.
The statement continued: "Economic growth enhances environmental protection. We can and must protect our environment without harming America's families. That is why my Administration is reducing unnecessary burdens on American workers and American companies, while being mindful that our actions must also protect the environment."
Trump also said science can benefit economic growth.
"Rigorous science is critical to my Administration's efforts to achieve the twin goals of economic growth and environmental protection," Trump's statement said. "My Administration is committed to advancing scientific research that leads to a better understanding of our environment and of environmental risks. As we do so, we should remember that rigorous science depends not on ideology, but on a spirit of honest inquiry and robust debate."
Twenty million Americans celebrated the first Earth Day in 1970, sparking the birth of the environmental movement. Enormous celebrations in hundreds of cities across the country eventually led to the creation of the Environmental Protection Agency.
(© Copyright 2017 CBS Broadcasting Inc. All Rights Reserved. The Associated Press contributed to this report.)
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