A major oilsands producer claims to have reduced its greenhouse gas emissions "intensity" over the past year, but an environmental activist calls that a "shell game."

Suncor admits in a report released Wednesday that its absolute emissions rose by 3.6 per cent between 2006 and 2007.

The company did say its emissions intensity has fallen by 25 per cent across the company and 44 per cent at its oilsands operation north of Fort McMurray, Alta.

When the company refers to emissions intensity, it means the amount of emissions created to produce a barrel of oil has decreased.

"What they don't talk about that much is overall emissions and the fact that they are producing way more barrels than they used to," Mike Hudema, a climate and energy campaigner with Greenpeace Canada, told Canada AM from Edmonton on Wednesday.

"Since 1990, Suncor's carbon emissions have more than doubled, and they're set to double again by 2012."

Climate activists have taken aim at the oilsands because they are considered Canada's "dirtiest" source of oil.

Hudema said it takes anywhere from three to five times as much carbon energy to produce a barrel of oil from the oilsands as to produce a barrel of conventional oil.

A Suncor spokesman wasn't available to speak to Canada AM.

The oilsands contain proven reserves of 173 billion barrels of oil, with a potentially recoverable reserves estimated to be 315 billion barrels, according to the Alberta government.

Conventional oil reserves in Alberta are in decline.

Investment in expanding oilsands capacity has driven Alberta's economy to frenetic heights in recent years.

Alberta's Premier Ed Stelmach, who won a huge election victory this winter, promised not to put the brakes on oilsands development.

His climate plan calls for a 14 per cent reduction in total emissions, compared to 2005 levels, by 2050. The Alberta plan centres on carbon capture and storage, which isn't yet a proven technology.

"We need to see reductions based on climate science," Hudema said.

Most climate scientists say the world needs to reduce its emissions to at least 50 per cent below 1990 levels by 2050 in order to stave off dangerous climate change.

Canada's Kyoto Protocol target calls for this country to cut its emissions by six per cent below 1990 levels by 2012.

Hudema said the oilsands expansion "will make it harder to address climate change in any meaningful way in Canada."

"By 2020, the industry is predicting that over 141 million tonnes of greenhouse gases are going to be emitted into the atmosphere by the tar sands," he said.

"To put that in perspective, that's almost double all the emissions of all the cars and trucks in Canada."