Using more than 1,200 individually painted tiles, youth climate activists with the nonprofit Our Climate constructed a giant mosaic on Boston Common this weekend. They arranged the tiles in the shape of a mother and calf pair of North Atlantic right whales, a critically endangered species threatened by climate change.

"As our ocean's acidity, salinity and temperature increases, we and the right whales are at a greater risk than ever before," said Izzy Goodrich, a 15-year-old Boston resident and climate activist. "Whales are the perfect rallying flag for devoted activists and climate-conscious politicians to fight to preserve the human race and push back against political corruption, corporate greed, extreme right wing ideology and the promotion of ignorance surrounding climate issues."

A young child examines every tile before placing them inside the whale mosaic on Boston Common. (Miriam Wasser/WBUR)

The day began around 10 a.m. when, against the backdrop of the State House, dozens of young people — and their adult allies and supporters — started arranging recycled fabric sheets into the shape of the two whales. They periodically paused their work to answer questions or talk about climate change with curious people walking by.

After the border was properly secured with wooden stakes, the teens placed the recycled cardboard tiles inside. They were aided by a few very young children, including an 8-year-old girl who said she was concerned about the fate of the right whales.

The activists supplied blank tiles and markers so people passing by the mosaic could partake in the art exhibit. (Miriam Wasser/WBUR)

The artistic prompt for the tiles was "what we stand to lose to climate change." Many students painted polar bears, whales and penguins, while others wrote more harrowing messages like, "my city," "water is life" and "our house is on fire." More than a few tiles included language about carbon pricing, one of Our Climate's main legislative priorities.

"We are advocating for some Massachusetts leadership on all sorts of climate policies, especially carbon pricing," Eben Bein, Our Climate's New England field coordinator, explained. "If we do not make polluters pay for their actions, young people will foot an enormous bill later. Those disasters will be devastating and expensive."

He called the mosaic project a call to action for adults and young people alike.

After completing the whale, youth activists pose for a drone photograph. (Miriam Wasser/WBUR)

Boston Latin student Punnya Kalapurakkel, 16, said young people need to be involved in climate action and policy "because we are going to be the next generation that has to take care of [the planet]. It's important that we show up earlier rather than later." Not doing so, she added, will result in catastrophic consequences for all life on Earth.