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The world's carbon emissions must be cut to zero by at least 2064 if the planet is to avoid the effects of climate change becoming out of control. 

Scientists from the UN have warned that emissions from human activities, such as burning fossil fuels, should hit net zero between 2055 and 2070 to prevent temperatures rising more than 2°C above pre-industrial levels.

Other greenhouse gases, such as methane, nitrous oxide and hydrofluorocarbons (HFCs), need to follow suit so that, overall, greenhouse gas emissions reach net zero between 2080 and 2100.

Scientists claim that carbon emissions from human activities, such as burning fossil fuels (pictured), should hit net zero between 2055 and 2070 to prevent temperatures rising more than 2°C above pre-industrial levels

A certain level of carbon is emitted naturally, but the report refers to reducing man-made emission to zero - referred to as net zero.

The stark report, by the UN Environment Programme (UNEP) said that emissions need to peak within a decade, with all greenhouse gas emissions halving by mid-century, in order to avoid sea levels rising and dramatic weather conditions, such as widespread droughts.

Countries have already agreed to limit temperature rises to no more than 2°C - beyond which dangerous impacts of climate change are expected - but UNEP said that if the world carries on as it is, greenhouse gas emissions will be 'way beyond safe limits'.

It warned that even if countries meet their existing pledges to cut emissions, the world will exceed the amount of greenhouse gases that can be emitted to keep temperature rises within safe levels - by 10 billion tonnes by 2020, and 17 billion tonnes by 2030.

Countries have already agreed to limit temperature rises to no more than 2°C - beyond which dangerous impacts of climate change are expected, such as melting ice caps and rising sea levels (illustrated) - but UNEP said that if the world carries on as it is, greenhouse gas emissions would be 'way beyond safe limits'

To have a good chance of staying below 2°C, greenhouse gas emissions should drop by around 15 per cent or more by 2030, compared to 2010 levels, and be at least 50 per cent lower by 2050 on the way to net zero emissions.

The report said that there could still be room for some emissions at the end of the century if they are compensated for by measures that take in carbon, such as planting trees, to achieve 'carbon neutrality'.

But delaying taking stringent action now until after 2020 will lead to higher costs and greater risks to society. 

The Emissions Gap report is published ahead of UN climate talks in Lima, Peru, which are working towards a new global deal to tackle climate change that it's hoped will be agreed in Paris next year.

UNEP executive director Achim Steiner said: 'An increase in global temperature is proportional to the build-up of long-lasting greenhouse gases in the atmosphere, especially carbon dioxide.

'Taking more action now reduces the need for more extreme action later to stay within safe emissions limits.'

WWF chief executive David Nussbaum said the report was another stark reminder of the 'worrying chasm' between what scientists said needed to be done to avoid dangerous climate change and what governments have promised to do so far.

'If we don't close this "emissions gap" within this decade, our task will not only become harder and more expensive, but threatens the very survival of some of the world's most vulnerable communities and habitats,' he said.

'Prevarication and delay are our enemies. As the report rightly notes, postponing rigorous action until 2020 will lock in much higher costs and risks later on. This is an unacceptable legacy to bequeath to our descendants.

'We must end the era of dirty fossil fuels and move to an era of clean renewable energy as fast as possible.

'We cannot ignore one of the report's key findings, namely, that energy efficiency offers a triple win: emissions reductions, energy security and green jobs.'