Millions of people in 180 countries celebrated Earth Day on Sunday, including many Canadians who used the occasion to pressure the Conservative government to honour its obligations under the Kyoto Protocol.

In Canada, one of the biggest Earth Day gatherings took place at a march in Montreal where people such as Shannahn McInnis urged the Harper government to meet its Kyoto promises.

Environment Minister John Baird predicted last week that meeting the greenhouse emission targets of Kyoto would bring on a recession.

Bloc Québécois Leader Gilles Duceppe, who was present at the Montreal march, condemned Prime Minister Stephen Harper for protecting Alberta oil interests over the health of Quebec's environment.

"Canada is getting rich off oil and Quebec is paying for it," Duceppe said.

In Ottawa, about 300 mostly young activists basked in the spring sunshine on Parliament Hill where they tossed balls and Frisbees while lending an ear to political speeches.

Green party Leader Elizabeth May predicted the Tory effort will be little more than a public relations ploy designed to camouflage the issue in advance of a federal election. 

"The Harper government understands the threat of climate change as an electoral threat," May said in an interview just before her speech. "They do not understand it as a threat to the lives of our children and grandchildren."

The Conservative government was notably absent at Earth Day events, but Baird delivered his message in television interviews.

New environmental measures

Baird told CBC News that the government's new environmental measures, which is expected to be revealed later this week, will force big industry to meet specific greenhouse gas emission targets.

The government will regulate 700 of the biggest polluters, not just force them to meet targets, but also require them to clean up "on the smog and pollution side as well," Baird said.

"It's a big part of the solution," he said. "It's not the entire solution, but it is definitely the single, biggest thing we can do."

In a CTV interview, Liberal Leader Stéphane Dion proposed that government charge industry a $20-per-tonne carbon levy that would go into an environmental fund and be repaid if companies cut their emission levels.

Dion has been careful to call the levy a deposit rather than a tax, a term that raises hackles in the Alberta oil patch.

Last week, Baird faced intense criticism from political opponents and environmentalists when he unveiled a study that warned of economic recession and soaring prices if the Kyoto treaty was enforced.

Liberal MP Pablo Rodriguez accused the Tories of using "politics of fear" to undermine the Kyoto treaty.

Solar-heated showers

On Sunday, NDP Leader Jack Layton and fellow MP Olivia Chow rode their bicycles on a sunny afternoon to join an estimated 250 people in the Toronto parade after taking showers with water heated by solar power. 

Smog, combined with rising temperatures, is an immediate threat in Canada's biggest city, where extreme heat alerts have been routine events in recent years. 

Paul Mero brought along his children, aged 8 and 6, saying he wants to instill the value of the environment in them. 

Mero noted he can insulate his home and replace inefficient light bulbs, but "the government needs to do the bigger things — put the infrastructure in place to encourage people to do these things."   

with files from the Canadian Press