I found the stuff in bedford is not fresh for me, and it is not easy to make mistake. In addition to bedford, the essay can be a problem. At first, I just wrote down what teacher said in class, but when I started to write the confusing things came out. The solar activity have no evident energy rising; however, the evaporation has accumulated in atmosphere more than it used to. I assumed that the carbon dioxide makes the earth warmer, then the water evaporate more than long time ago. In one word, human are still the main cause...