Climate Change 2007: The Physical Science Basis
Svante Arrhenius, a Swedish chemist, predicted in 1896 that the Earth’s temperature would increase by four to six degrees Celsius if carbon dioxide had a two-fold increase as a result of humans burning fossil fuels. However, until 1960, this prediction was ignored until notable changes began to emerge across the planet. Since the beginning of the Industrial Revolution, the greenhouse gases carbon dioxide, methane, and nitrous oxide have increased in the atmosphere, thus increasing the atmosphere’s overall warming. This warming has become apparent through increases in global average temperatures of the air, global average temperatures of the oceans, and the melting of snow and ice as well as the rise in sea levels. Furthermore, numerous changes are occurring to the climate including changes in the amounts of precipitation, ocean salinity, wind patterns, the frequency and intensity of storms, and Arctic ice melts. Such changes are largely the result of anthropogenic influences, especially through the burning of fossil fuels. Also, the effects of these excessive greenhouse gases are expected to continue regardless of whether or not we stop the burning of fossil fuels. In light of these expected changes, researchers have created several models to predict future scenarios. Therefore, and as depicted in one of the models, even if society switches to sustainable energy sources, the affects of current and past activities will still be felt for centuries to come.
The media often reports on the situations arising from extreme weather events around the globe such as storms, droughts, and major heat waves. Hurricane Katrina is one of the most memorable events because of the amount of destruction that resulted from storm surges, large amounts of rain, and high winds. Intense cyclonic storms on land, such as tornadoes, are also popping up on weather maps where they are not normally seen. Because of excessive heating, more significant pressure systems are being created, thus increasing the wind speeds and updrafts of warm air masses. Surface temperatures over either the water or land help to determine the intensity of the storms because higher temperatures cause increased evaporation and increased updrafts.
Furthermore, since these changes are occurring, the public is going to have to find ways of adapting to and reducing the amount of damage associated with more intensive weather. Such a feat can be more easily accomplished in developed countries where they have the funds and resources available to research new technologies to withstand the forces of nature. Lesser developed countries have no disaster relief systems, and therefore suffer greatly in droughts and floods when crops and livestock are killed.
Events that correlate with precipitation, such as forest fire frequencies, are also going to increase. Decreased precipitation levels will cause droughts which may lead to fires. With warmer temperatures, more water will be evaporated into the atmosphere, thus drying areas further. As a result, water sources are going to become more overburdened as they will be used to fight fires, assist agricultural practices through irrigation, and become reduced in size as a result of increased evaporation. Freshwater shortages are already occurring because of population and agricultural demands.
Through this dire forecast of the future, many people should be prompted to decrease their fossil fuel consumption in the hope of reducing the effects of climate change and ecosystem changes brought on by increased heating. For those people who believe there is no hope for the future because the changes necessary to adapt our current ways of thinking and lifestyles required to offset global heating and climate change are too numerous, they may choose to do nothing. After all, our existence on Earth is finite and we will one day die off, though mainly because of the consequences of our own actions, like many of the other species that we have seen disappear. It is just a matter of time, and global warming may only decrease the amount of time we have remaining.
Easton T. Classic edition sources: environmental studies. New York: McGraw-Hill; 2009. pp. 127-35.
Related link.....
CBC. In depth: Hurricane Katrina-Hurricane Katrina timeline. [Online]. Avail from: http://www.cbc.ca/news/background/katrina/katrina_timeline.html#top [2009]
