Marianne Lavelle

Earth's CO2 Level Nears 400 ppm

news.nationalgeographic.com — Robert Kunzig Published May 9, 2013 An instrument near the summit of Mauna Loa in Hawaii recorded a long-awaited climate milestone today: the amount of carbon dioxide in the atmosphere there has exceeded 400 parts per million (ppm) for the first time in 55 years of measurement-and probably more than 3 million years of Earth history.

Earth's CO2 Level Nears 400 ppm

news.nationalgeographic.com — Robert Kunzig Published May 9, 2013 An instrument near the summit of Mauna Loa in Hawaii recorded a long-awaited climate milestone today: the amount of carbon dioxide in the atmosphere there has exceeded 400 parts per million (ppm) for the first time in 55 years of measurement-and probably more than 3 million years of Earth history.

Pictures: Bolivia Seeks Economic Energy in Vast Lithium Stores

news.nationalgeographic.com — In a flood-prone expanse high in the Andes, Bolivia holds the world's largest lithium reserves. Can this crucial battery ingredient provide an economic charge?

Solar Impulse, the Solar-Powered Plane, Begins U.S. Expedition

news.nationalgeographic.com — Kate Andries Published May 3, 2013 A solar-powered aircraft able to fly day and night began the first leg of its journey this morning on a mission to become the first aircraft to fly coast-to-coast across the United States without using a single drop of fuel.

Efficient Light Bulb Study Generates Heated Debate

greatenergychallengeblog.com — When we published a story this week on a study that showed the negative consequences of environmental messaging on light bulbs, we suspected the subject would spark a lively debate-and our readers delivered. The post garnered more than 2,500 Facebook "likes," 582 tweets, 93 Google+ likes, and more than 90 comments.

Pictures: Bolivia Seeks Economic Energy in Vast Lithium Stores

news.nationalgeographic.com — In a flood-prone expanse high in the Andes, Bolivia holds the world's largest lithium reserves. Can this crucial battery ingredient provide an economic charge?

Pro-Environment Light Bulb Labeling Turns Off Conservative Buyers, Study Finds

news.nationalgeographic.com — Brian Handwerk Published April 30, 2013 How many conservatives does it take to change a light bulb? A more intriguing question might be, "How many conservatives can you persuade to switch to energy-efficient light bulbs?"

A Tale of Two Ponds: NYC Park After the Storm

news.nationalgeographic.com — Hurricane Sandy left New York City's Gateway National Recreation Area in pieces, but there may be a silver lining to the storm.