And that's the difference between problems that are additive, like CO2, 这个就是可添加性问题，像二氧化碳问题， which we go slowly up and then we tip, and problems that are depletive, in which we lose what we have, which
Last year I showed these two slides so that demonstrate that the arctic ice cap, 去年我给各位展示了两个关于北极冰帽的演示， which for most of the last three million years has been the size of the lower 48 states, has shru
Happy New Year! Everybody. This week, I traveled to Cleveland, Ohio, to talk with folks about the biggest challenge we face as a country – rebuild our economy so that, once again, hard work pays
