Hindu: The present challenge faced by the world lies in returning to a path of sustainable development and this is much bigger than meeting the threat of climate change, R.K. Pachauri, chairman of the Intergovernmental Panel on Climate Change (IPCC), said here on Saturday. For over 150 years, the world pursued the process of industrialisation and the path of development was clearly proving more and more unsustainable. What was required was “to bring our forces and intellectual capacity in …