Instead some pores are filled with water, and others with air. ... An example of capillary forces exceeding gravity is capillary rise in a thin glass tube, where water is lifted upwards against the force of gravity. ... As a result, water in the unsaturated zone is preferentially drawn into small spaces over large ones, which tend to be occupied by air. ... Toxic waste that has leaked from containment facilities has seeped into the ground. ... The primary source of surface water is spring discharge from highly fractured plutonic rocks into streams along mountain foothills (INEGI, 1986). ...

• Word Count: 696
• Approx Pages: 3
• Has Bibliography
• Grade Level: Undergraduate

Agricultural expansion into forestland is the primary cause of tropical deforestation. ... Chemicals from waste dumps in some metropolitan areas are draining into backyards. Pesticides are leaking through the soil into drinking water wells in our agricultural belts. ... Refrigerators were designed to cool, but their coolants seep into the atmosphere and thin the Earth's protective shield. Americans want clean air, yet few are enthusiastic about the inconvenience of automobile exhaust inspections. ...

• Word Count: 700
• Approx Pages: 3
• Grade Level: Undergraduate

Although opinions are various, they both consider global warming is climate change that is leading to an increase in the overall air and water temperature. ... Earth absorbs energy from the sun; at the same time, Earth re-radiates the energy back into space. Normally, the thin layer of atmosphere can trap a portion of the outgoing radiation, which keeps Earth's temperature within a comfortable region; nevertheless, the layer of atmosphere is being thickened by a great deal of carbon dioxide and other greenhouse gases caused by humans. ...

• Word Count: 1061
• Approx Pages: 4
• Grade Level: Undergraduate