Global Climate Change

Global warming or greenhouse effect are no longer new terms for current people in the world. They are the aliases of global climate change, especially referring to the significant rising of global average temperature, which as commonly known is due to the greenhouse gases, mostly those emitted by human activities.
Greenhouse effect is never a newly-produced effect. It has been long existing, probably dated back to the birth of the earth, and undoubtedly it was a good influence of its origin because it was the greenhouse effect that provided warm environment for plants to grow and for humans and animals to live. Those natural greenhouse gases, mainly carbon dioxide (CO2), methane (CH4), water vapor (H2O) and Nitrous Oxide (N2O) act like a blanket covering over the earth to prevent the loss of heat energy. Nevertheless, things reverse themselves when reaching an extreme. The good effect of those greenhouse gases turned out to be a very bad and worrying one because human beings have been producing too much of them, and also adding new greenhouse gases, mainly chlorofluorocarbons (CFCs), especially as human stepped into the industrial era (Figure 1), let alone the huge leap happened since 1900s if we see a big picture in terms of history (Figure 2).
A huge amount of CO2 and N2O have been coming from the burning of fossil fuels, namely petroleum, coal, natural gas, which were largely relied on in every aspects of transportation, manufacturing, power energy production and so forth. CFCs is a good example of this. It was the refrigerant widely used in the 20th century. Though CFCs had been banned already, its extremely long life span allows it to stay at troposphere for up to 40 to 100 years, acting as greenhouse gas for all those years. The emission of these greenhouse gases is attributed to human’s consumption and considerably high demands of life as well. For instance, methane is a by-product of growing rice paddies and livestocks. Meat consumption, especially beef (ruminants) consumption contributes a lot to producing not only methane but also other greenhouse gases (Figure 3). Surprisingly, water vapor (H2O) turns out to be the most important contributions to the greenhouse effect. As the earth is getting warmer and warmer owing to those trapped heat energy, more and more water is evaporating into atmosphere and makes great reinforcement to other greenhouse gases. What’s more, Due to rapid development of human civilization, deforestation and desertification are getting increasingly severe, which enhance the global warming as we are reducing the carbon sink, a large area of trees absorbing tons of carbon dioxide. All these factors mentioned above seem to strengthen the effect of each other and make a vicious circle.
The global climate change is really causing enormous overall consequences, both directly and indirectly. The most obvious one is the rising temperature. Up to 2ºF average increase of global annual temperature has been measured. This means there can be a much bigger range of temperature increase in temperate latitude. More extreme weathers and natural disasters are taking place, increased storm frequency and intensity, changes of storm pattern and precipitation amounts, reduction of soil moisture content, which leads to all different consequences like flooding, drought and desertification. Other problems caused by global warming such as the rise of sea level, threats to ecosystem, shortage of food supply and the spread of tropical diseases, to name just a few.
Arctic and Antarctic ice sheet melting and changes in marine ecosystem are two main consequences of global warming, and they are closely related to a certain degree.
A lot of us may be quite familiar with the cartoon that a polar bear is sitting on a small piece of ice which can barely hold its body and the bear is even holding an umbrella to prevent the insolation (Figure 4). It is ironic but thought-provoking. Nowadays, on the