Climate change concern

Global temperature rises could exceed "safe" levels of two degrees in some parts of the world in many of our lifetimes if greenhouse gas emissions continue to increase, two research papers published in the journal Nature warned.

"Certain levels of climate change are very likely within the lifetimes of many people living now, unless emissions of greenhouse gases are substantially reduced in the coming decades," said a study released on Sunday by academics at the English universities of Reading and Oxford, the UK's Met Office Hadley Centre and the Victoria University of Wellington, New Zealand.

"Large parts of Eurasia, north Africa and Canada could potentially experience individual five-year average temperatures that exceed the two degree threshold by 2030 - a timescale that is not so distant," the paper said.

Two years ago, industrialised nations set a two degree warming as the maximum limit to avoid dangerous climate changes, including more floods, droughts and rising seas, while some experts said a 1.5 degree limit would be safer.

It is widely agreed among scientists that global pledges so far for curbing greenhouse gas emissions are not strong enough to prevent "dangerous" climate change.

Next month, nations will meet in Durban for the next UN climate summit, where a binding pact to reduce emissions looks unlikely.

Instead, a global deal might not emerge until 2014 or 2015.

The study found that most of the world's land surface is likely to experience five-year average temperatures that exceed two degrees above pre-industrial levels by 2060.

A separate study by academics at Zurich's Institute for Atmospheric and Climate Science, the Potsdam Institute for Climate Impact Research and the UK's Met Office Hadley Centre, among others, said it would be challenging to limit temperature rises to two degrees. To achieve a greater than 66% chance of limiting a rise, emissions will probably need to peak before 2020.