The Great Lakes
The Great Lakes contain about 23,000 km3 (5,500 cu. mi.) of water, covering a total area of 244,000 km2 (94,000 sq. mi.) The Great Lakes are the largest system of fresh, surface water on Earth, containing roughly 21 percent of the world's supply and 84 percent of North America's supply. Only the polar ice caps contain more freshwater.
In spite of their large size, the Great Lakes are sensitive to the effects of a wide range of pollutants.
Without water, life would not exist. It is a prerequisite for all human and economic development.
Nearly one billion people – about one in eight – lack access to clean water. More than twice that many, 2.5 billion people, don’t have access to a toilet. Only 2.53 percent of Earth’s water is fresh, and some two-thirds of that is locked up in glaciers and permanent snow cover.
Climate change is a problem that is affecting people and the environment. Earth-orbiting satellites and other technological advances have enabled scientists to see the big picture, collecting many different types of information about our planet and its climate on a global scale. Studying these climate data, collected over many years, reveals the signals of a changing climate.
Greater energy efficiency and new technologies hold promise for reducing greenhouse gases and solving this global challenge.