Green news roundup: Environment app, birdsong and butterflies

Green news on your iPhone • Environment news on your iPhone? There's an app for that A free, customisable app for iPad and iPhone, built by Taptu and powered by Guardian content, makes it easy to get all the latest green news, comment and images while on the move Environment news • International airlines will be charged for carbon emissions, EU court rules • 'Green deal' will fail, government's climate advisers warn • Scientists to study psychological benefits of birdsong • British fishing industry lands controversial EU deal • MoD reveals 15 radioactive UK sites • Extreme weather baffles British butterflies On the blogs • Paper bags or plastic bags: which are best? • Does using a dehumidifier help to reduce heating costs? • Even Canada doesn't believe its own spin on tar sands • Caroline Lucas: We need to design a new economic order • George Monbiot: Why is it so easy to save the banks – but so hard to save the biosphere? • What is the best way to draught-proof stripped wooden floors? Multimedia • Flying with birds in BBC's Earthflight - in pictures • RSPCA young photographer awards - in pictures • The week in wildlife – in pictures • 'Non-stuff' Christmas gifts for nature lovers - in pictures Best of the web • SciDev.netClimate change killing trees across the Sahel, says study • ChinaDialogue: The problem with green rankings • Yale Environment 360: 'The whalers have won absolutely everything': veteran activist For more of the best environment comment and news from around the web, visit the Guardian Environment Network . ...And finally • Facebook 'unfriends' coal and 'likes' clean power Agreement to power its operations using clean and renewable energy follows a two-year campaign by Greenpeace