"Canadians are ready to make polluters pay ... and they're not afraid of paying more" for cleaner technologies or to reduce their own ecological footprint, David Suzuki said at the cusp of a three-month tour of Canada.

Suzuki is renowned for his books, television and radio broadcasts on nature and the environment since the 1970s.

Based on his dialogue with 30,000 Canadians, he outlined five priorities in the fight to stem global warming: building more public transit, introduction of a carbon tax, tougher environmental legislation, more protections for species at risk, and the creation of a national program to penalize polluters.

"It's clear that public opinion has undergone a fundamental shift. Canadians are no longer debating whether or not climate change is occurring. Rather they're discussing what to do about it," Suzuki said.

"Canadians have changed their thinking, but they need leadership to change their behavior," he said. "Politicians have an opportunity to do the right thing because the people are behind them."

Thursday, Environment Minister John Baird outlined a doomsday economic scenario if Ottawa imposed tough new measures to cut carbon emissions in order to meet Canada's Kyoto Protocol commitment.

He told a senate committee reviewing a private member's bill to try to force the minority Conservative government to meet its Kyoto timetable that these emissions cuts would have "a devastating effect on the Canadian economy."

More than 275,000 Canadians would lose their jobs by 2009 and Canada's unemployment rate would rise by 25 percent, he predicted.

Canada's economy meanwhile would decline by more than 6.5 percent relative to current projections in 2008, falling about 4.2 percent or about 51 billion Canadian dollars (45 billion US) below the 2007 level.

"That implies a deep recession in 2008," Baird said.

"I believe this is a massive and unacceptable cost for Canadian families," he concluded.

Canada had agreed under the international Kyoto Protocol to reduce carbon emissions to 6.0 percent below 1990 levels by 2012, but a 2006 government environmental audit found emissions had instead increased by 26.6 percent.

Prime Minister Stephen Harper has maintained that the Kyoto targets, agreed to by a previous Liberal government, are unattainable.

Suzuki, whose science TV show "The Nature of Things" has been syndicated in more than 40 countries, dismissed Baird's economic forecast, saying Canada faced "total economic ruination" if Ottawa does nothing to cut CO2 emissions.

Long skeptical about climate change and its causes, the US administration earlier this month finally acknowledged the "global challenge" facing the planet and called for international solutions.

"Climate change is clearly a global challenge and we all recognize that it requires global solutions," Sharon Hays, leader of the US delegation at the Intergovernmental Panel on Climate Change (IPCC) said April 6.

A summary of the IPCC's latest technical report warned of devastating damage on all continents from global warming, saying that the resulting climate change is set to hit poor countries hardest, and threatens nearly a third of the world's species with extinction.