Over the past decades, the Earth has continually faced disasters. Many scientists have identified them as signs of climate change. The causes of climate change can be divided into two main factors: natural events and human activities. “As human beings, we are prone to confuse what is unprecedented with what is improbable. In our daily experience, if something has never happened before, we are usually safe to assume it won't happen in the future, but waiting can kill you and climate change is one of those exceptions », Expressed the former President of the United States. Vice President Al Gore (Climate Change Quotation, Internet). Although it is not certain whether these changes are caused by nature, human activities are certainly the main contributors to atmospheric changes. This essay will illustrate the connections between human activities and natural events in the context of climate change. Climate change is a long-term change in the statistical distribution of weather patterns over periods of time. These may be changes in average weather conditions or a change in the distribution of weather events relative to an average. Climate change is a global phenomenon; its effects therefore impact every corner of the Earth (Defining Climate Change, 2011). For example, climate change can decrease or increase precipitation, affect agricultural crop yields, influence human health, increase the risk of dangerous floods, strong winds, increased temperature, stimulate changes in forests and other ecosystems, or even modify our energy supply. According to the IPCC Fourth Assessment Report, in 2100, global average temperatures are expected to increase by 2°F to 11.5°F, depending on the level of future greenhouse gas emissions...... middle paper..... .particularly by burning fossil fuels. Compared to natural processes, our CO2 production was about 29 gigatons and this is only a small amount, but it accumulates in the atmosphere because the land and ocean can only absorb about 40 % of additional CO2. Thus, it appears that human-caused CO2 emissions are altering the natural balance of the carbon cycle and the extra amount is cumulative because the natural process cannot absorb all the extra CO2 (How Human CO2 Emissions Compare to natural CO2 emissions, 2007). In conclusion, it is true that human activity has played a greater role than natural events as a contributor to climate change. And without prevention, the Earth's temperature will reach a critical level in the future. All measures must therefore be taken as quickly as possible to ensure that all human species can live comfortably and safely on earth...