For more than 20 years, international climate talks have been dominated by a schism between those who created the problem of climate change (largely the United States and nations of the European Union) and those who would greatly contribute to it moving forward (largely China and India). But as climate negotiators meet in Lima, Peru, this week and next, and news reports are full of gloomy predictions that the negotiations will produce little, there are increasing signs that this stalemate may have been broken. This emerging shift is due in large part to China and its decision to break ranks and join the United States in making commitments to reduce greenhouse gas emissions.

One critical question now is whether India – the country that has stood by China’s side in climate talks and is now the world’s third-largest emitter – will follow suit in a meaningful way at the Lima negotiations. And there seems to be a surprisingly high chance that India will.

China and India share a common domestic problem – one that has motivated China’s leaders to act, and could motivate India’s. That is, the fossil fuels that cause climate change also produce local air pollution. This has risen to deadly levels, with all of the Chinese and Indian cities that the World Health Organization monitors for air pollution failing the organization’s test for acceptable levels of airborne particulate, widely believed to be the most dangerous air pollutant for human health. More than half of these cities also fail their own countries’ particulates standards…