UN goal on global temperature unrealistic: Study

The historic agreement reached at last year's UN conference in Paris to hold the increase in the global average temperature to well below 2 degrees Celsius above pre-Industrial Revolution levels is almost impossible to achieve, says a study.

"It would require rates of change in our energy infrastructure and energy mix that have never happened in world history and that are extremely unlikely to be achieved," said Glenn Jones from Texas A&M University at Galveston.

The overall goal of "Paris Agreement", signed by officials representing more than 190 countries, is to replace fossil fuels which emit huge amounts of carbon dioxide into the atmosphere leading to higher temperatures, with renewable energy sources such as solar and wind power and biofuels.

"Just considering wind power, we found that it would take an annual installation of 485,000 five-megawatt wind turbines by 2028. The equivalent of about 13,000 were installed in 2015. That's a 37-fold increase in the annual installation rate in only 13 years to achieve just the wind power goal," Jones added.

Similar expansion rates are needed for other renewable energy sources as well, said Jones along with Kevin Warner, a marine biology researcher at Texas, in a paper published in the journal Energy Policy.

"To even come close to achieving the goals of the Paris Agreement, 50 percent of our energy will need to come from renewable sources by 2028, and today it is only 9 percent, including hydropower. For a world that wants to fight climate change, the numbers just don't add up to do it," Jones noted.

"If we don't worry about global warming and the two-degree Celsius goal, we can continue to burn known fossil fuel reserves, but even here we will have to achieve more than 50 percent renewable energy by 2054, but warming will exceed 2.5 to 3 degrees Celsius," he warned.