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Plans to artificially turn the Arctic Ocean white in an attempt to reduce the impacts of global warming are likely to fail, new research has shown.

This would involve floating white grains or producing microbubbles in the ocean to help reflect some of the sun's heat back into space, ultimately reducing the melting of sea ice.

But a new study has now found that despite the huge cost and effort that would be required, such an extreme approach would have little impact on stopping melting in the Arctic.

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The white sea ice in the Arctic Ocean (shown above) helps to reflect some of the sun's heat back into space but as it reduces, due to global warming, there are fears it will increase the impacts of climate change. Some scientists have proposed artificially turning the sea white to replicate the effect of the ice and reduce warming

The proposals are the latest in a number of technological approaches, known as geoengineering, to be put forward by scientists as a way of slowing climate change. 

Researchers at the Carnegie Institution for Science in Stanford found that for every square mile of ocean 'whitened', just three quarters of a mile of sea ice could be restored.

The ocean whitening would have even less effect on the permafrost in the Arctic Circle as this would still melt and release huge amounts of methane - a potent greenhouse gas.

Whitening of the ocean would also have impacts further afield, causing wetter and milder winters in the south west United States and cooler conditions in the eastern US.

The findings come amid fears from environmental campaigners who fear that geoengineering could have drastic impacts on wildlife and the environment as a whole.

Dr Ken Caldeira, an expert on global ecology at the Carnegie Institution for Science who took part I the study, said: 'Simply put, our results indicate that whitening the surface of the Arctic Ocean would not be an effective tool for offsetting the effects of climate change caused by atmospheric greenhouse gas.

'Furthermore, it is not clear to me that there is a technologically feasible way of actually doing this, and even if you could do it, the direct negative consequences of reducing the amount of sunlight available to marine ecosystems could be huge.'

The most recent report by the United Nation's Intergovernmental Panel on Climate Change last year suggested that it may be necessary to use geoengineering to reduce the impacts of global warming.

Whitening the Arctic Ocean may restore sea ice but not climate

The researchers ran simulations of what would happen to the Arctic sea ice if the ocean was whitened using geoengineering technology (as shown in the example above) and found it would have a modest impact. On the left is the extent of September sea ice without ocean whitening (abledo) and right is after six years

It warned that as carbon emissions have already committed the world to warming, it may be necessary to tinker with the atmosphere to keep temperature rises below 2°C.

Among the measures put forward are spraying aerosols into the atmosphere to reflect sunlight, and increasing the iron content of the sea to increase carbon uptake.

Others have suggested outlandish ideas such as putting mirrors into orbit to reflect some of the heat from the sun.

However, such steps have drawn criticism due to fears they would have unintended, and sometimes harmful, consequences on the environment.

Whitening the Earth's polar regions would help increase the albedo effect – where sunlight is reflected back into space by the white surface.

There are fears that as the Arctic warms, melting of the ice will reduce this effect and cause more heat to be absorbed by the dark ocean and ground - creating a feedback loop of warming.

By artificially whitening the ocean, some geoengineers have suggested it could help reduce this effect and prevent further melting in the region.

Dr Ivana Cvijanovic, a climate researcher now based at Lawrence Livermore National Laboratory, who led the research, said: 'By the middle of the century, the Arctic Ocean is predicted to be ice-free during part of the year.

'This could create substantial ecological problems in the Arctic, including habitat range changes and loss of biodiversity. 

The researchers found that the amount of permafrost in the northern hemisphere would continue to reduce even with ocean whitening technology, as shown in the graph above, which shows how much permafrost would be left compared to the current day (1xCO2) with and without the geoengineering being applied

This graph shows how surface air temperature conditions would change over a 50-year period. The black line indicates current carbon dioxide levels, the solid red line depicts four times pre-industrial carbon dioxide levels, the blue lines represents different levels of sunlight being reflected back into space by whitening

'However the problem is not only local-a number of studies have indicated that Arctic sea ice loss can affect weather patterns across the northern midlatitudes, including Europe, most of North America, and much of Asia.'

Using specially developed climate models, the researchers, whose work is published in the journal Environmental Research Letters, to examine how effective Arctic whitening would be in a world where carbon dioxide levels reached four times the pre-industrial levels.

Under current models this would result in the Arctic warming by around 10°C (18°F).

Dr Cvijanovic said whitening would have little impact on melting if applied across the whole ocean.

But she added: 'Ocean whitening and the sea ice recovery achieved in this way could lead to wetter and milder winter conditions in the southwestern United States and cooler conditions in the eastern United States.'