Climate change is defined, according to National Oceanic and Atmospheric Administration of the US (2007), as a long-term shift in the statistics of the weather. It could be presented, for instance, as a change in normal climate level at a given place and time of year. The main evidence of climate change includes rising sea levels, melting glaciers and increasing extreme weather. What causes climate change can be divided into natural aspects and human aspects. The former refers to volcanic eruptions, biotic processes, variations in solar radiation received by Earth, while the latter includes burning fossil fuels, damaging forests and other human activities.
There is statistical evidence that clearly shows the rapid climate change. In the past 20th century, sea level around the globe increased close to 8 inches. However, the rate rose to almost double that of the last century over the past twenty years. (Church & White, 2006). In Antarctic and Greenland, the ice sheets have shrunk in mass. Data from the NASA's Gravity Recovery and Climate Experiment show that, Antarctica had an ice decease of some 152 cubic kilometers between 2002 and 2005, while Greenland had an yearly decrease of 150 to 250 cubic kilometers from 2002 to 2006. In terms of temperature, since the late 19th century, surface temperature of the earth has gone up some 2.0 degrees Fahrenheit, which is resulted in large part from increasing human-made emissions, including carbon dioxide, into the atmosphere. The year of 2016 was the warmest year in historical records, and eight in twelve of its months were also the warmest on record for those respective months (NASA, 2017).
In conclusion, in face of the global challenge of climate change, which can cause the reduction of biological diversity, damages to agricultural production and threats to coastal cities and countries, the typical countries of China and the US has taken different policies. China, as a developing country, used to seek rapid development while polluting its environment, on which its long-term development is based. Therefore, it now pursues a low-carbon economy and actively takes part in global efforts. In addition, it of importance for China to gain more leading place and force itself to improve its renewable energy sectors by doing so.