Levels of carbon dioxide in the atmosphere have jumped abruptly, raising fears that global warming may be accelerating out of control.
Measurements by US government scientists show that concentrations of the gas, the main cause of the climate exchange, rose by a record amount over the past 12 months. It is the third successive year in which they have increased sharply, marking an unprecedented triennial surge.
Scientists are at a loss to explain why the rapid rise has taken place, but fear that it could show the first signs that global warming is feeding on itself, with rising temperatures causing increases in carbon dioxide, which then go on to drive the thermometer even higher. That would be a deeply alarming development, suggesting that this self-reinforcing heating could spiral upwards beyond the reach of any attempts to combat it.
The development comes as official figures show that
It also coincides with a new bid to break the log jam over the
Mr Byers is co-chairing with US Republican Senator Olympia Snowe a new taskforce, run by the
The carbon dioxide measurements have been taken from the 11,400ft summit of
They have been taking the readings from the peak – effectively breathalyzing the planet – for the past 46 years. It is an ideal site for the exercise, 2,000 miles from the nearest land and protected by freak climatic conditions from pollution from
The latest measurements, taken a week ago, showed that carbon dioxide had reached about 379 parts per million (ppm), up from about 376ppm the year before, from 373ppm in 2002 and about 371ppm in 2001. These represent three of the four biggest increases on record (the other was in 1998), creating an unprecedented sequence. They add up to a 64 per cent rise over the average rate of growth over the past decade, of 1.8ppm a year.