London (PTI): Scientists have warned that climate change could soon begin to get out of control, with concentration of carbon dioxide in the atmosphere touching a record high.

Scientists at the Mauna Loa observatory in the US state of Hawaii say that CO2 levels in the atmosphere now stand at 387 parts per million (ppm), up almost 40 per cent since the industrial revolution and the highest for at least the last 650,000 years.

Based on some 11,000 ft high volcano, the Mauna Loa observatory is regarded as producing among the most reliable data as its remote location ensures that its sensors are not confused with other possible sources of the gas.

According to the US National Oceanic and Atmospheric Administration, the latest figures also confirm that carbon dioxide, the chief greenhouse gas, is accumulating in the atmosphere faster than expected.