The continent of Antarctica is the fifth largest in the world. Situated in the Southern Hemisphere, the area measures over 4.5 million square miles (12 million sq. km). Ice averaging 1.18 miles (1.9 km) in thickness covers nearly the entire area; only 2 per cent remains uncovered. Antarctica experiences some of the harshest environmental conditions in the world. Frigid temperatures below −81° Fahrenheit (−63° C) and strong winds are common. Antarctica is also home to countless icebergs, which drastically range in size and shape. Anywhere from 50 to 99 per cent of an iceberg is hidden below the water. Fields including climatology and biology have taken an interest in these floating ice masses. By studying the factors influencing iceberg disintegration, climatologists hope to learn more about global warming. As floating pieces of ice melt, nutrients leak into the surrounding water. Biologists are interested in better understanding the effects these nutrients have on the aquatic ecosystem.