called for immediate action to address some of our biggest environmental challenges. he's been speaking to our science editor, david shukman, during the filming of a new documentary series, the green planet. this is a thermal camera. and it will tell me the difference between the surrounding temperature and the temperature in the centre of a daisy flower. the surroundings — 12 degrees. in the centre of the flower — 21. new technology to film the humble daisy. and action, david. at kew gardens in london, we had rare access behind the scenes to the making of green planet. but it looks like you get a lot of enjoyment out of... out of making these programmes. well, they're all old friends, aren't they? that's the nice thing.