Climate change is a serious global environmental concern. It is primarily caused by the building up of greenhouse gases (GHG) in the atmosphere. The global increases in carbon dioxide concentration are due primarily to fossil fuel use and land use change, while those of methane and nitrous oxide are primarily due to agriculture. Global Warming is a specific example of the broader term climate change and refers to the observed increase in the average temperature of the air near earth's surface and oceans in recent decades. Its effect particularly on developing countries is adverse as their capacity and resources to deal with the challenge is limited. Many studies have shown that the global atmospheric concentrations of carbon dioxide, methane and nitrous oxide which are the most important greenhouse gases, have increased markedly as a result of human activities in the society since 1750 and now far exceed pre-industrial values.