The Earth is made up of five interdependent spheres: the geosphere (lithosphere), hydrosphere, biosphere, cryosphere, and atmosphere. The spheres are so closely connected that a change in one sphere often results in a change in one or more of the other spheres. Changes that take place within an ecosystem are referred to as events. Events can occur naturally or they can be caused by humans. An event can cause changes to occur in one or more of the spheres or an event can be the effect of changes in one or more of Earth’s four spheres. This cause and effect relationship between an event and a sphere is called an interaction. Water in the lake seeps into the cliff walls behind the dam and becomes groundwater or evaporates into the air. Which spheres are interacting in this example?
A) hydrosphere only
B) hydrosphere and atmosphere
C) biosphere, hydrosphere, and cryosphere
D) hydrosphere, geosphere, and atmosphere

Project: analyze it! data collected over the past century shows the earth currently in a slight warming trend, with an increase over that period of a little more than 1.0°f in average global temperature. the question of what is causing the trend has sparked controversy in both scientific and political circles. some argue that while temperature fluctuations are a normal part of the earth's climate cycles historically, an increase in co2 produced by industrial pollution and other forms of human activity is contributing to and even accelerating the increase, potentially leading to significant environmental problems. others argue that pollution-caused co2 is not a factor and that the increase is caused by natural cycles alone. objectivesresearch credible positions for and against the existence of global warming. write a short essay briefly outlining each perspective. directions locate two well-researched, credible articles, one for and one against global warming. after reading the articles, write a 300-word essay addressing the following: what is global warming, as described in the articles? what arguments are given for and against the idea. what actions are recommended by each position? in your opinion, what can be learned from the debate? what would you like to do next?