With the summer winding down, European airlines are ramping up efforts to encourage passengers to keep taking to the skies. The Hungarian airline Wizz Air, for example, has just launched an All You Can Fly scheme, offering unlimited flights for a yearly subscription. Other flight carriers are holding flash winter sales. But climate activists say promotions like these are irresponsible and governments need to put an end to them. The World’s Europe correspondent Orla Barry has more.