Which would have produced more CO₂: the Icelandic volcano or the planes which would have flown if it hadn't erupted?  Find out in this QotW.  Plus, we ask if altitude can affect the hours of daylight one experiences.

• What has a bigger greenhouse effect, the emissions from the recent eruption in Iceland, or the plane... - Questions
• Wallpaper paste volcanoes - why some volcanoes go bang! - Kitchen Science
• Did the Icelandic volcano produce more carbon than the grounded flights would have? - Naked Scientists Science Podcasts and Science Radio Shows
• Geoengineering - How We Could Change the Climate - Interviews
• No need to change the lightbulb - we already have - Features
• How do Volcanoes affect Ocean Biodiversity? - Interviews