2255

clipped from brneurosci.org Another issue that people are confused about is the rate of increase of carbon dioxide. Some people think that CO2 is rising dramatically. This is probably because of graphs like the one below. However, in hard science journals, the graph above would be considered dishonest, because the y-axis starts at 290 instead of zero. This misleads the reader into thinking that CO2 levels have undergone a huge increase when in fact, CO2 levels have only increased by 23.7% since 1900. According to the US Department of Energy, only about 14.8% of this increase, or 11.88 ppm, is man-made. The remaining 68.5 ppm is caused by natural forces, such as volcanoes and forest fires [26]. From this, researchers have estimated that, when water vapor is taken into account, anthropogenic CO2 contributions cause about 0.117% of the Earth's total greenhouse effect [25]. At the current rate of increase, CO2 will not double its current level until 2255.