350: Science --> Poetry --> Music

350 parts per million is the "safe upper limit" for CO₂ in our atmosphere presented by NASA scientist Jim Hansen in December 2007 and widely agreed upon.  From that number 350.org .was born. On October 24, 2009, 350 Poems celebrated an international day of climate action with a posting, from poets all around the world, of 350 poems of 3.5 lines each --  each responding to concern for man-made climate change.