Why Toba Matters What can a volcanic eruption that occurred almost 75,000 years ago teach us about today's world of air pollution, global warming, and climate change? Heaps, says Dr. Drew Shindell, a climatologist at NASA's Goddard Institute for Space Studies in New York. For starters, knowing what the massive upheaval of Indonesia's Toba supervolcano did to the planet's climate (it might have cooled global temperatures enough to kill vegetation for years on end and perhaps hasten an ice age) offers sobering insight into what pumping billions of tons of chemicals into the atmosphere as we're now doing could result...