A physicist at Columbia University in New York says his team has taken a major step in creating a ‘carbon scrubber’.

If he’s right, Klaus Lackner’s work may help us suck carbon dioxide out of the atmosphere and combat global warming. OK, we still need somewhere to put all that carbon dioxide, but one thing at a time.

“I wouldn’t write across the front page that the problem is solved, but this will help,” he told the Guardian. “We are in a hurry to deal with climate change and will be very hard pressed to stop the train before we get to 450ppm. This can help stop the train.”

According to the Guardian, Lackner’s breakthrough is in working out how “absorbent plastic sheets called ion exchange membranes” can trap carbon dioxide and then be made to release it when exposed to humid air. A prototype scrubber would cost about £100,000 and fit in a shipping container, says the paper.

As both the Guardian and the Telegraph point out, you’d need millions of these devices to off-set our current emissions as each one will suck up a tonne of carbon dioxide a day.

Last year Richard Branson and Al Gore offered $25 million for any invention that can remove ‘significant’ amounts of carbon dioxide from the atmosphere. This, we reported at the time, would probably have to be about a billion tonnes a year.

So Lackner’s machines are going to have to get a little cheaper or a lot more efficient before he can turn a profit on that prize.