The federal government is set to announce that it is almost halfway to meeting its emissions-reductions target — a significant leap in progress over the past year.

The Canadian Press has learned that when Environment Canada releases its next update on greenhouse gas emissions trends in August, the report will show that Canada is almost 50 per cent of the way toward meeting its 2020 goal.

That's a big jump from the 25 per cent announced a year ago.

Multiple sources say the surge is a result of provincial measures, more efficient technology and a recent international agreement that credits Canada for its large forests.

"We're trending in the right direction," said one source on condition of anonymity.

The report is expected to be made public within a couple of weeks.

Specifically, it will show that existing government measures will make greenhouse gas emissions fall to 720 megatonnes in 2020, instead of the 850 megatonnes that would have resulted from no government action.

The 720-megatonne estimate is 65 megatonnes lower than the total at this time last year.

It means that if nothing else changed on the policy front, the actions Canadians and their governments are taking now would reduce emissions by almost half the amount required under Canada's international commitments.

Ottawa has pledged under the Copenhagen accord that by 2020, Canada will have cut its emissions to 607 megatonnes, or 17 per cent below 2005 levels.

Part of the progress is math. In the past, Canada didn't count land-use change or forestry in its calculations, but now, after international negotiations, it can. That accounts for 25 megatonnes of the surge, sources said.

But the rest of the advance is because newly constructed buildings and new vehicles are far more efficient than they were in the past, and because provincial policies for reducing emissions are proving to be effective.

Quebec is implementing a cap-and-trade system to encourage a low-carbon economy, while British Columbia has implemented a carbon tax.

Plus, some federal regulations may be beginning to have an effect, sources said.

In April, Environment Canada said emissions in 2010 were no longer increasing even though the economy had resumed growth after the recession. The upcoming emissions trends report, which is subject to stringent peer review, assumes that the "decoupling" persists, sources said.

A spokesman for Environment Minister Peter Kent would not comment on the emissions trends report.

"We're in the process of crunching our numbers and look forward to releasing this year's trend report in the coming weeks," said director of communications Rob Taylor.

Still, it's an open question whether federal and provincial policies will be introduced and implemented fast enough to finish the job in time.

"If we steadfastly stick to the sector-by-sector approach ... it's just not going to be possible. There's too much time lag to develop them, and they don't do enough," said Matt Horne, acting director of the climate change program at the Pembina Institute, an environment think tank.

Ottawa has rejected both a cap-and-trade system and a carbon tax, and has instead opted to impose rules on key industrial sectors that are major emitters of carbon.

But only two sets of rules have been introduced so far.

New coal regulations are in the final stages of being ready, and oil and gas will likely be next, in early 2013. But Horne fears the federal government is in the midst of weakening its plans for coal regulations. And Ottawa faces intense pressure from the oil patch to go easy in that sector too.

Numerous experts, as well as the National Round Table on the Environment and the Economy, and the federal environment auditor, have all warned that Ottawa won't come close to reaching its target if it relies solely on those regulations.

That's because they are taking a long time to develop, and an even longer time to actually affect the way industries carries out their business.

In the meantime, companies are starting up new ventures under the existing regime, and locking in high carbon emissions -- keeping levels high for decades to come.

"Despite making progress in reducing greenhouse gas emissions, Canada is not on track to achieve the federal government's 2020 reduction target of 17 per cent below 2005 levels," the round table said June in its last major report before shutting its doors due to government funding cuts.

"Canada will not achieve its 2020 GHG emission reductions target unless significant new, additional measures are taken. More will have to be done. No other conclusion is possible."

Putting a price on carbon and investing heavily in hydro-electric power would be key ways to meeting the target, the advisory body has suggested.

"It would be tough to meet them [the target] regardless. There's not much time left," said Horne. "I'm not sure we can get all the way there."