Because of our energy-intensive lifestyle and human activities, the earth is now facing various environmental problems: Extreme weathers, rise of sea levels, melt of icebergs, to name but a few. While some people consider global warming to be the most pressing issues which we have at the moment, others believe that deforestation has a more catastrophic effect of the nature. In my opnion, the later claim is more plausible, and hence this essay will then discuss the above views and provide evidence as to why cutting off trees is a more serious matter.