Global warming is a cause for concern because even the rise of the average temperature on Earth by even a few degrees, can cause far-reaching effects. Due to industrialization and the increased use of fossils fuels for energy since the Industrial Revolution, many pollutants have been linked to global warming. For instance, carbon oxides (a result of burning of fossil fuels) are considered to be a greenhouse gas with links to global warming. Nitrogen oxides, produced due to combustion of fossil fuels are also greenhouse gases.
Other gases involved in global warming are methane, tropospheric ozone and chlorofluorcarbons. Scientists have researched global climate change for the past 50 years and have noted that temperatures have increased over the past century, and it can not be attributed solely to natural causes. They conclude that air pollutants have caused most of this global warming.
The effects of global warming are far-reaching. As more carbon dioxide is absorbed by the seas, the ocean will become more acidic--not all organisms will be adapted to this lower pH and could die. Polar ice caps are melting leading to a rise in sea levels. When ice caps melt, this creates a positive feedback loop, which leads to more global warming. The ocean rose 0.2 m due to thermal expansion in the 20th century--rising sea levels could increase flooding in coastal areas. Mountain glaciers are quickly melting and disappearing as is the ice in Greenland and Antarctica.
Precipitation patterns will change in different parts of the world. Some areas will have more frequent droughts, others more snow and rain and flooding. The number of storms originating over warm surface waters may increase. Some areas may experience earlier times for species to migrate and for flowers to bloom, and this will upset the balance of various ecosystems. Also, the basis of the ocean food chains--zooplankton--may die off, and this will effect the higher trophic levels that depend on them for food.
Extinction rates are predicted to accelerate when many organisms are unable to adapt to the changing climate. Heat-related illnesses affecting the sick and elderly may increase. Productivity in crops can increase due to excessive carbon dioxide levels. This may directly cause an increase in agricultural pests. These examples are some of the effects of global warming.