Rising Sea Levels June 2014 | Page 4

Issues

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Issues

Overview

Over the past century, the global sea level has started to rise at an alarming rate. It has risen by about 4-8 inches due to two main factors: thermal expansion and melting of glaciers and ice caps (4).

What is Thermal Expansion?

Thermal expansion is the largest contributor to sea level rise. The concept of thermal expansion is essentially that when water heats up, it expands (5). The particles of water start to move at an increasing rate, maintaining a greater separation and thereby expand the substance. Every drop of water in the ocean expands infinitesimally multiplied by the entire ocean mass, it adds up (6).

Global Warming

Thermal expansion and the melting of ice caps and glaciers both result from global warming. When humans burn fossil fuels, massive amounts of heat trapping gases are emitted into the atmosphere (5). The Earth's temperature then rises, and the ocean absorbs about 80% of the heat (4).

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