求一篇关于"全球变暖意义"的英文文章?

Global climate unexpected turn of events is warm
Earth’s atmosphere is ideally composed for life, with just the right mix of elements to sustain and support plants and animals. This mix includes small traces of greenhouse gases such as carbon dioxide, methane and nitrous oxide. Because they are composed of molecules of three atoms or more – C02, CH4, NO2-- they thicken up the atmosphere and help trap incoming sunlight after it has bounced off the Earth in the form of heat. Without them, the Earth would be a frozen iceball with temperatures hovering around 0 deg. Fahrenheit.

Greenhouse gases are a good thing, but we’ve all heard about the problems of too much of a good thing and that is clearly the case with greenhouse gases. Human activities are making massive changes in global atmospheric chemistry. Since the dawn of the industrial revolution 250 years ago, carbon dioxide has increased in the atmosphere by 31%, methane by 151% and nitrous oxide by 17%. And we have