Earth day and the Precautionary Principle

During school today I was shown the first video below, advertising Earth Hour. It struck me that the primary claim, 'The need for urgent action is now indisputable' in some quarters remains very questionable. A possible TOK and Aim 8 teaching point?  Does the very nature of the event highlight / ignores what could be done all year round? e.g. Why is Sidney harbour bridge decorated through the night? Yes the Eiffel tower looks pretty all lit up but... I have therefore included ...