A report by independent energy think tank Ember has warned that India’s coal production, expected to rise from 982 million to over 1.5 billion tonnes by 2030, could significantly increase methane emissions. Methane, a potent greenhouse gas, is the second-most abundant after carbon dioxide and has a more immediate but powerful effect on global warming. India's coal mining is a key source of these emissions, leaking from vents, pits, and underground cracks.