A study presented at United Nations climate talks does not think that global warming limit of 2 degrees Celsius is safe and in fact, new target should be 1.5 degrees Celsius.

Researchers were of the view that harmful effects of global warming like heat waves and sea level rise are increasing. These factors suggest the need for 'radical transition' to a greener economy.

The research unveiled that impacts of global warming are one rise despite the fact that the average temperature has increased only 0.85 degrees Celsius above pre-industrial times. Zou Ji, a co-leader of the UN review of consultations about science policy for governments working on a UN climate deal in Paris in December, was of the view that negative impacts are something that can be seen now.

A common belief is that government promises with regard to curbs on greenhouse gas emissions were not enough strong to stay below the 2 degrees Celsius goal. "Limiting global warming to below 2°C necessitates a radical transition ... not merely a fine tuning of current trends", unveiled the report.

In order to witness such a level of change there will be need deep cuts in greenhouse gases, shift of dependence from fossil fuels like coal and oil to renewable energies like wind, hydro and solar power.

Report's co-leader Andreas Fischlin said that the concept of 2°C was considered to be safe. But now it is better if it is seen as an upper limit.