The 2012 target was to restrict emissions of six climate- warming gases, including carbon dioxide, to 53.226 million tonnes. The latest Greenhouse Gas Inventory shows the actual adjusted figure was 55.6 million tonnes.
The new figures represent a rise of 0.8 per cent over the past year, in contrast with an overall drop of nearly 30 per cent from the 1990 baseline level.
The recent increase in emissions north of the Border mirrors the UK trend, with reports showing a country-wide rise of 2.9 per cent since 2011.
Despite this, Scotland leads the UK in cutting emissions with a reduction of 29.9 per cent between 1990 and 2012. This compares with 23.9 per cent for England, 17.7 per cent for Wales and 15 per cent for Northern Ireland. The EU reported a drop of 18.5 per cent over the period.
Scotland’s aim is for an 80 per cent decrease by 2050.
Despite exceeding its emissions limits for the third time, environment minister Paul Wheelhouse said Scotland remained on track to meet its flagship target for a 42 per cent reduction by 2020.
“Scotland chose to have stretching targets because we were aware of the scale of the challenge of climate change,” he said. “However, since then we have also improved the method for calculating emissions. That was the right thing to do, but it now shows the task is in fact even harder than parliament and society realised in 2009.
“The Scottish Government has put together a package of measures to demonstrate our resolve to meet future targets.”
The package includes a new cabinet sub-committee dedicated to tackling climate change as well as plans for action on cycling infrastructure, energy efficiency, transport planning and electric vehicles.
Environmental campaigners criticised the missed target but described the new measures as “important first steps” in battling global warming.
Gina Hanrahan, of Stop Climate Chaos Scotland, said: “While acknowledging changes to how we measure greenhouse gas emissions has on this occasion made the targets harder to meet, this shouldn’t distract from future efforts to develop a low-carbon economy.”
She added: “These are important first steps and we will need to build on them to realise the full potential of the Climate Change Act.”
Green MSP Patrick Harvie said: “This latest failed target will strengthen the growing mood in support of bolder action from government.
“There’s agreement across Holyrood for a series of additional policies to cut our greenhouse gas emissions, and it’s not good enough for ministers to wheel out the same old rhetoric.”
The latest missed target is “deeply embarrassing for a Scottish Government that continually heralds them as world-leading”, Labour environment spokeswoman Claire Baker said.
“The minister must now fully explain why, under his watch, emissions have risen in the past year.”
The baseline for measuring emissions has been adjusted by 5.4 million tonnes since targets were set. If the 2012 target had been revised accordingly, Scotland would have met it with 1.647 million tonnes to spare.