The British Meteorological Department's new study has warned that global warming could result in a rise of 4 degree Celsius by the year 2060.
According to the Guardian, unchecked global warming could bring a severe temperature rise of 4C within many people's lifetimes, as warned by the new report for the British government that significantly raises the stakes over climate change.
The study, prepared for the Department of Energy and Climate Change by scientists at the Met Office, challenges the assumption that severe warming will be a threat only for future generations, and warns that a catastrophic 4C rise in temperature could happen by 2060 without strong action on emissions.
"We've always talked about these very severe impacts only affecting future generations, but people alive today could live to see a 4C rise," said Richard Betts, the head of climate impacts at the Met Office Hadley Centre, who will announce the findings today at a conference at Oxford University.
"People will say it's an extreme scenario, and it is an extreme scenario, but it's also a plausible scenario," he added.
According to scientists, a 4C rise over pre-industrial levels could threaten the water supply of half the world's population, wipe out up to half of animal and plant species, and swamp low coasts.
A 4C average would mask more severe local impacts: the Arctic and western and southern Africa could experience warming up to 10C, the Met Office report warns.
The study updates the findings of the 2007 report of the Intergovernmental Panel on Climate Change (IPCC), which said that the world would probably warm by 4C by 2100 if greenhouse gas emissions continue to rise.
The Met Office scientists used new versions of the computer models used to set the IPCC predictions, updated to include so-called carbon feedbacks or tipping points, which occur when warmer temperatures release more carbon, such as from soils.
When they ran the models for the most extreme IPCC scenario, they found that a 4C rise could come by 2060 or 2070, depending on the feedbacks.
According to Betts, "It's important to stress it's not a doomsday scenario, we do have time to stop it happening if we cut greenhouse gas emissions soon."
Soaring emissions must peak and start to fall sharply within the next decade to head off a 2C rise. To avoid the 4C scenario, that peak must come by the 2030s, he added.