Introduction

Nearly 200 hundred years ago, the English poet Samuel Coleridge wrote the now famous phrase “Water, water, everywhere, Nor any drop to drink.” The painful dilemma of a man becalmed at sea with no fresh water immortalized in the Rime of the Ancient Mariner now faces far more than a few unlucky sailors. Very little of Earth’s water is fresh – less than 3% of the total. As the human population grows, as industrial and agricultural water demands escalate, and as streams and groundwater sources become more and more polluted, chronic and acute water shortages are becoming increasingly common. Already 40% of the world’s population lives in areas subject to severe water shortages.

The planet’s greatest stores of freshwater lie far away from the arid, heavily populated regions that need it the most. Nearly 70% of all fresh water is locked in the polar ice caps. Just the new icebergs that form every year around Antarctica hold enough water to meet the needs of every person on Earth for several months. Longstanding proposals to tow icebergs to lower latitudes where their valuable water can be harvested have been met with both skepticism and interest. To date, no successful attempts have been made.

In this activity, you will investigate some of the logistical problems involved in moving enormous chunks of ice long distances through often turbulent seas.

Instructions

The exercise below gives you six opportunities to take an iceberg in tow and haul it to a seaport where fresh water is needed. In each box, click on the iceberg and observe what happens. View all six animations, and then answer the questions that follow.