Zero global emissions are needed by the end of 21 century if we want to stay below the two degree Celsius threshold and prevent ourselves from the severe impact of climate change, says IPCC Vice Chairman, Prof Jean Pascal van Ypersele. He further says in case of increase in warming the impact will be more severe. He was delivering a lecture on "Challenges and Opportunities of Climate Change" jointly organized by SDPI and Belgian Embassy in Islamabad. Raja Taimur Hassan has the story...