Photo by comedy_nose via Flickr CC Dear Pablo: Two airlines have recently switched from paper flight records to iPads. Is this really an environmental improvement? TreeHugger recently covered news of two airlines (, followed by United Continental) that

Photo by comedy_nose via Flickr CC Dear Pablo: Two airlines have recently switched from paper flight records to iPads. Is this really an environmental improvement? TreeHugger recently covered news of two airlines (, followed by United Continental) that have switched to iPads to replace about 38 pounds of paper in the cockpit and reduce greenhouse gas emissions by an estimated 3,208 metric tons. Writer Jaymi Heimbuch asks "But when you stop to think that the savings is equivalent to about two people flying across the country, is the savings really worth it?" Well, is it? And is the iPad really better than all that paper?... Read the full story on TreeHugger

Image credit: Bernd Sieker, used under Creative Commons license. Dear Pablo: Does installing commercial rooftop solar PV (with the dark-colored PV cells) negate the effect of painting that same roof white to alleviate the "heat island" effect in

Image credit: Bernd Sieker, used under Creative Commons license. Dear Pablo: Does installing commercial rooftop solar PV (with the dark-colored PV cells) negate the effect of painting that same roof white to alleviate the "heat island" effect in cities? When the sun's energy arrives at the Earth's surface it is either reflected or absorbed. When more energy is absorbed than normal, such as in a city with lots of dark asphalt and concrete, we get a "heat island" effect. We're exploring if solar panels contribute to this effect, and if so, whether or not this impact is offset by their benefits.... Read the full story on TreeHugger