A rolling protest petition car is parked Saturday in downtown Toronto during a protest of Canada's stand at the climate change talks in Bali, Indonesia. From costume parades in the Philippines to a cyclists' protest in London, marches took place in more than 50 cities around the world to coincide with the two-week Climate Change Conference, which runs through Friday.

London ? Skiers, fire-eaters and an ice sculptor joined in worldwide demonstrations Saturday to draw attention to climate change and push their governments to take stronger action to fight global warming.

From costume parades in the Philippines to a cyclist’s protest in London, marches were held in more than 50 cities around the world to coincide with the two-week U.N. Climate Change Conference, which runs through Friday in Bali, Indonesia.

Hundreds of people rallied in the Philippine capital, Manila, wearing miniature windmills atop hats, or framing their faces in cardboard cutouts of the sun.

“We are trying to send a message that we are going to have to use renewable energy sometime because the environment, we need to really preserve it,” high school student Samantha Gonzales said. “We have to act now.”

In Taipei, Taiwan, about 1,500 people marched through the streets holding banners and placards saying “No to carbon dioxide.” Hundreds marched outside the conference center in Bali. At a Climate Rescue Carnival held in a park in Auckland, New Zealand, more than 350 people lay on the grass to spell out “Climate SOS.”

At the Brandenburg Gate in Berlin, ice sculpture artist Christian Funk carved a polar bear out of 15 tons of ice as a memorial to climate protection.

Christmas markets throughout Germany were switching off the lights for five minutes, and British cyclists pedaled into Parliament Square in London. In Helsinki, Finland, about 50 demonstrators ground their skis across the asphalt along the main shopping street, calling for decision makers to give them their snowy winters back.

Fire-eaters blew billowing clouds of flames at a rally in Athens, Greece.

In London, demonstrators braved the cold, rainy December weather to descend on Parliament Square, wielding signs marked: “There is no Planet B.” Bikers circled the square earlier in the morning to protest the city’s traffic and its effect on global warming, organizers said.

The London protest has singled out one particular target – President Bush – calling his administration the biggest obstacle to progress at the Bali talks. Organizers plan to underline the point by ending the protest in front of the U.S. Embassy.

“Bush has been forced to change his language on climate but continues to be the major obstacle to progress,” said Britain’s Campaign against Climate Change. “We will not just stand by and allow Bush – or anyone else – to wreck the global effort to save billions of lives from climate catastrophe.”

Washington has found itself increasingly isolated at the climate talks. The U.S. position that technology and private investment – not mandatory emissions cuts – will save the planet has drawn criticism.

But Americans too protested Saturday. In Massachusetts, about 50 demonstrators took a quick “polar bear” plunge into the bracingly cold waters of Walden Pond.

“We want our elected leaders – the congressmen, senators and the president – to realize that global warming is a serious problem that needs their leadership,” organizer Roger Shamel said.

Three protesters dressed in polar bear costumes carried banners that read: “Please save the Earth for our babies.”

In Fairbanks, Alaska, protesters skied a frigid slope wearing just bathing suits or underwear.

It was about 19 degrees during the ski, unusually warm for this time of year.