Fears tipping point is past

SCIENTISTS fear global warming has passed an ominous tipping point after Nasa satellite data showed the already relentless melting of the Arctic increased greatly during the northern hemisphere’s hot summer months.

One expert even speculated that summer sea ice would be gone in five years.

Greenland’s ice sheet melted nearly 19 billion tonnes more than the previous high mark, and the volume of Arctic sea ice at summer’s end was half what it was just four years earlier, according to the Nasa data.