visited a few sites... even took a train ride. the final stop, back to the united nations, where he used his address to press for stronger commitments to end global warming, with a stark warning of the enduring consequences, if countries didn't step up. we will see desertification, drought, crop failure and mass movements of humanity on a scale not seen before, not because of some unforeseen natural event or disaster, but because of us, because of what we are doing now, and our grandchildren will know that we are the culprits. it's time for humanity to grow up. the prime minister chose to focus solely on the subject of climate change. he used this global stage to make the strongest pitch he could, ahead of the climate conference coming up soon in glasgow, which, he said, would be a critical point for humanity. a critical