The functional role of a particular species in an ecosystem is called its niche .
Niche : the position (way of life) of a species in an ecosystem in terms of the physical characteristics (such as size, location, temperature, and pH) of the area where the species lives and the function of the species in the biological community.
Video: Humpback Whales' Feeding Frenzy
A niche may be described in terms of space utilization, food consumption, temperature range, requirements for moisture or mating, and other factors.
A niche is not a habitat (a location), it’s a pattern of living.
The part of its fundamental niche that a species occupies is called its realized niche .
Realized niche : the range of resources that a species uses, the conditions that the species can tolerate, and the functional roles that the species plays as a result of competition in the specie’s fundamental niche
The realized niche is only a small portion of its fundamental niche which reduces competition among species.
Rain and snow carry the sulfuric acid back to the Earth’s surface.
This acidified precipitation is called acid rain .
Acid Rain : precipitation that has a pH below normal and has an unusually high concentration of sulfuric or nitric acids, often as a result of chemical pollution of the air from sources such as automobiles exhaust and the burning of fossil fuels
The major cause of ozone destruction is a class of chemicals called chlorofluorocarbons (CFCs) .
Chlorofluorocarbons: hydrocarbon in which some or all of the hydrogen atoms are replaced by chlorine and fluorine; used in coolants for refrigerators and air conditioners and in cleaning solvents; their use is restricted because they destroy the ozone layer
CFCs were invented in the 1920s because were considered extremely stable, supposedly harmless, and a nearly ideal heat exchanger.
The average global temperature has been steadily increasing for more than a century, particularly since the 1950s.
In the Earth’s long history there have been many such periods of global warming , often followed by centuries of cold.
Scientist hypothesize that sunspot cycles may contribute to these cyclical changes in global temperature, but many scientists suspect that human activity may be significantly contributing to global warming.