LA Times: This week, President Obama is the chief guest of Prime Minister Narendra Modi at India's Republic Day celebrations. At the close of the historic visit, the two leaders are expected to announce cooperation on a suite of climate and clean energy measures, with the ultimate goal of reining in India's rapidly rising carbon dioxide emissions.
But during his visit, the president, just like New Delhi's 25 million residents, will be exposed to another kind of dangerous carbon pollution: black carbon....