Dwyer 1 Jeffery D. Dwyer The causes and effects of Global Warming. Like many pioneer fields of study, there are uncertainties associated with the science of global warming. This does not imply that all things are equally uncertain. Some aspects of the science are based on well-known physical laws and documented trends, while other aspects range from 'near certainty' to 'big unknowns'. Scientists know for certain that human activities are changing the composition of Earth's atmosphere. …showed first 75 words of 1216 total…

…showed last 75 words of 1216 total…