The carbon tax is succeeding in cutting greenhouse gas emissions in the parts of the economy where it applies, Labor and the Greens say, as they vow to resist Abbott government plans to scrap the key climate change policy.

Figures due out later this week from the National Greenhouse Gas Inventory will show emissions for the year to June - the first year of the carbon tax - fell just 300,000 to 545.9 million tonnes, the government said.

The government estimates the carbon tax bill is $8 billion, implying it cost about $26,700 per tonne of emissions abated.

That emissions total, though, indicates emissions were 2 per cent lower in the year ending June than the 12 months to March 31.

Fairfax Media sought a breakdown of the national emissions total from the office of Environment Minister Greg Hunt.

If the inventory figures for the year to March are any guide, though, power sector emissions are sliding.

Industries only partly covered by the carbon price, or not at all - such as agriculture, transport and fugitive emissions from gas and coal operations - are seeing rising emissions, nullifying the gains from electricity generators.

John Connor, chief executive of the Climate Institute, said the release of overall emissions figures without showing the carbon tax's direct impact was misleading: ‘‘It is at best disingenuous to leak a proportion of it and not have the full report at the same time.’’

Mr Hunt released a similar statement in October with the March greenhouse emissions total, but with much less media pick-up than resulted from Sunday's partial disclosure to Murdoch newspapers.

Repeal push

The government has used the flat emissions result to push its case that the carbon tax - now at $24.15 per tonne - should be repealed when the Senate sits this week, and be replaced by a direct-action plan to pay polluters to cut back.

A limited reduction in national emissions, as shown in the year-to-June figures, would not in itself be new.

Inventory figures available on the government's website for the year to March also reveealed almost no change in emissions. They edged 0.1 per cent lower to 557 million tonnes over that period.

The June quarter, though, saw a cut of 11.1 million tonnes on an annual basis, or about 2 per cent, from that March total.

The March 2013 annual figures also detailed which sectors are experiencing emissions growth and which are in decline - trends unlikely to have changed significantly in the April-June period.

For the year to March, emissions from the carbon tax electricity sector, which is affected by the carbon tax, fell 12.1 million tonnes, or 6.1 per cent.

Non-taxed emissions jump

That decline – partly due to slumping demand but also a carbon tax-prompted switch away from black coal-fired power plants – was masked by big increases in areas of the economy only partly affected by the carbon price.

For instance, fugitive emissions from the gas and coal mining industry jumped 12.7 per cent in the year to March to 45.8 million tonnes. Both industries continue to expand rapidly.

In transport, another growing sector, emissions rose 3.1 per cent in the 12 months to March 31, while emissions from agriculture rose 3 per cent.

While aviation, rail and marine transport, for instance, has to pay a carbon price, general transport does not. Similarly, while fugitive emissions face a carbon price, most gas for processing gets free permits and the coal industry has access to compensation to help limit the carbon cost.

The government used the total emissions to the year to June – without revealing its breakdown by sector – to press Labor and the Greens to drop their opposition in the Senate to its carbon tax repeal package.

The inventory figures show the "tax is a rolled-gold failure”, Mr Hunt told journalists on Sunday.

"We have an $8 billion-a-year tax with virtually no impact," he said. "There couldn't be a clearer demonstration of an utter carbon con.

“There can be no more excuse, no more delay, for [Opposition Leader Bill] Shorten to stand in the way of repealing the carbon tax,” he said.

Opposition environment spokesman Mark Butler said the release of more complete greenhouse gas figures would show emissions from electricity generation had dropped 6 per cent while driving a 25 per cent increase in renewable energy.

“This information flies in the face of Tony Abbott's last-ditch attempt to bully the Senate into agreeing to scrap an effective climate change policy without having a credible alternative,” Mr Butler said.

“The government doesn't believe in the climate change science and doesn't believe in effective climate change action.”

Australian Greens leader Christine Milne said the government “can pick, choose and release data to suit its own ideological position against action on global warming but that won't change the fact that the price on pollution is working. We will continue to see bigger and bigger cuts as the scheme comes to maturity.”

The Greens intend to call on the Coalition to reveal its plans for emissions in sectors not covered by the emissions trading scheme.

“Deforestation from land clearing and fugitive emissions from coal and gas are increasing. What will Direct Action do to stop that?” said Senator Milne.

Mike Raupach, a climate scientist with the CSIRO, said the future expansion of the mining industry will make it harder for the government to meet the bipartisan target of cutting Australia's greenhouse gas emissions by 5 per cent on 2000 levels by 2020.

‘‘Anticipated developments in a variety of industries, particularly coal seam gas, open the possibility for a further emissions increase," Dr Raupach said. "The Direct Action scheme would need to both overcome (the increase) in other areas, or exceed it, to get down to five per cent below (2000 levels).