Answer to Question 1
Global warming is the gradual increasing of average global air temperature. Average global surface temperatures have increased by about 0.74C over the last century. Although that increase may seem insignificant, it should be noted that average temperatures during the last Ice Age were only 5C lower than they are today. The prevailing scientific view is that greenhouse gases-primarily carbon dioxide, nitrous oxide, and methane-accumulate in the atmosphere and act like glass in a greenhouse, thereby causing global warming. Global increases in carbon dioxide are due primarily to increases in the burning of gasoline, oil, and natural gas. As forests are cut down or burned, fewer trees are available to absorb the carbon dioxide (trees and other plant life use carbon dioxide and release oxygen into the air). Increases in methane and nitrous oxide are primarily due to agricultural practices.
The effects of global warming could be devastating. As ocean/sea levels rise, some island countries, as well as some barrier islands, will go under water and disappear. Low-lying coastal areas will become increasingly vulnerable to storm surges and flooding. Global warming is anticipated to affect regions in various ways. As average temperature rises, some areas will experience heavier rain, whereas other areas will become arid from receiving very little rain. Global warming will result in shifts of animal and plant habitats; some species may not survive.
Answer to Question 2
c
The range of sugar maples could be reduced by global warming
Species of reef-building corals may be able to adapt to warming waters by relying on algae
Global Patterns of Intergroup Relations: A Continuum
Projections of global temperature depend heavily on the level of future greenhouse gas emissions
Global energy consumption is rising rapidly
Global list of Threatened Species