With the Conservatives set to unveil the details of their plan to regulate major industrial polluters, both environmentalists and industry are grumbling.

Environment Minister John Baird gave a preview on Wednesday before his major announcement set for Thursday.

"Our goal is very simple: greenhouse gas emissions are going way up and we want them to go way down," Baird told reporters Wednesday.

"That's why we're excited about our plan and our initiative . . . it's real, it's measurable and Canadians can hold us to account. We're not going to make commitments and promises we can't deliver."

Here's the broad view of the Tory plan:

• Stop the rise in greenhouse gas emissions within three to five years
• Cut emissions by 150 million tonnes, or 20 per cent from current levels, by 2020
• Cut air pollution in half by 2015

But the new targets mean the Tories have given up on trying to meet the Kyoto Accord targets that Canada ratified in 2002, critics say.

Kyoto calls for a six per cent cut below Canada's 1990 level by 2012. However, greenhouse gases have risen steadily in Canada and are were 27 per cent above 1990 levels as of 2004.

The previous Liberal government delivered a plan in April 2005 that would have achieved the Kyoto target, it claimed. The Conservatives, who opposed Kyoto's ratification, cancelled that plan after taking office in early 2006.

This looming plan drew fire from environmentalists.

"This is legislating an increase in emissions in the short term, and coming nowhere close to meeting the Kyoto targets and deep reduction targets that science is telling us we need to be aiming at," said Jaisel Vagdama of the Pembina Institute, an environmental think tank.

"This is not about comparing one party to another, this is about Canadians needing to stand up and defend climate, and what we have is a government defending industry and not defending the climate for our children," said the Sierra Club's John Bennett on Wednesday.

However, some business groups also sound gloomy.

"It will be painful,'' said Michael Murphy, policy head of the Canadian Chamber of Commerce. "You are talking about adding a regulatory burden and we're talking about both greenhouse gases and air emissions.''

Baird has recently said that trying to meet the Kyoto target would cause an economic collapse and the loss of 275,000 jobs, although he didn't warn of any dire economic consequences on Wednesday.

Christopher Green, a McGill University economist who has supported Baird's analysis, said doing so would require foreknowledge of how much new technology can contribute to meeting the target.

"This gives us more time than Kyoto, so the target is more plausible,'' he said.

Jayson Myers of Canadian Manufacturers and Exporters said it isn't known yet which sectors of the economy will fare worst.

"Certainly if we'd tried to get to Kyoto, it would have been much worse than this," he said. "But this issue is so politicized that we may be seeing requirements that are not achievable or that can only be achieved by doing serious harm to the economy."

Alberta's oilsands sector, one of the worst industries with respects to GHG emissions, is particularly holding its breath.

While tens of billions of dollars of investment are planned in oilsands projects, EnCana Corporation CEO Randy Eresman said those plants aren't high-priority investments.

"So, it's really a question of when do you choke, what extra burden is added on so that your project doesn't go ahead," he said.

Climate change's threat

In February, the Intergovernmental Panel on Climate Change report said it was 90 per cent likely that Earth's climate is warming and that human activity, particularly the burning of fossil fuels, is the reason why.

Earlier this month, the IPCC released its impacts report, which laid out some of the possible consequences of global warming if it isn't checked.

By 2050, about 20 to 30 per cent of the Earth's species could face extinction, and that's with a modest average surface increase of 1.5 to 2.5 degrees Celsius. Two billion people could face water shortages, and food production will drop in the lower latitude regions, the IPCC said.

If the temperature rises much beyond two degrees, the consequences become progressively more severe.

Holding the world's temperature rise to two degrees or less would require keeping carbon-dioxide equivalent levels below 450  parts per million. The atmosphere currently has about 380 parts per million CO2 in it.

Because greenhouse gases tend to linger in the atmosphere and have a cumulative effect, scientists say if action is delayed on cutting them, the cuts will have to be deeper in the future -- and more expensive -- if we wish to head off catastrophic climate change.

A report by economist Nicholas Stern for the British government last fall said fighting climate change would cost about one per cent of global economic output annually by 2050, but doing nothing could cut that output by five to 20 per cent.

With files from The Canadian Press