Can emerging technology defeat global warming? The United States has invested tens of billions of dollars in clean energy projects as our leaders try to save our crumbling economy and our poisoned planet in one bold, green stroke. Are we finally on the brink of a green-energy "power surge," or is it all a case of too little, too late?
The air around us is not just empty space; it is an integral part of the chemistry of life. Plants are made from carbon dioxide, nitrogen nourishes the soil and oxygen gives us the energy we need to keep our hearts pumping and our brains alive. But how did we come to understand what air is made of? How did we come to know that this invisible stuff around us contains anything at all?
NOVA follows a team of volcano sleuths as they embark on a worldwide hunt for an elusive volcanic mega-eruption that plunged the medieval earth into a deep freeze. The mystery begins when archaeologists find a hastily dug mass grave of 4,000 men, women, and children in London. At first they assume it's a plague pit from the Black Death, but when they date the bones, they're a century too early. So what killed off these families? The chronicles of that time describe a run of wild weather that devastated crops and spread famine across Europe. NOVA's expert team looks for the signature of a volcanic eruption big enough to have blasted a huge cloud of ash and sulfuric acid into the atmosphere, which chilled the entire planet. From Greenland to Antarctica, the team finds telltale "fingerprints" in ice and soil layers until, finally, they narrow down the culprit to a smoldering crater on a remote Indonesian island. Nearly 750 years ago, this volcano's colossal explosion shot a million tons of rock and ash into the atmosphere. Across the globe, it turned summer into winter. What would happen if another such cataclysm struck again today?
Modern life would be impossible without plastic – but we have long since lost control over our invention. Why has plastic turned into a problem and what do we know about its dangers? This video is a collaboration with UN Environment and their Clean Seas campaign, If you want to take action to turn the tide on plastics, go to http://www.cleanseas.org and make your pledge.