Air pressure is caused by the weight of the air pressing down on the Earth, the ocean and the air below. Air pressure is also known as atmospheric pressure and barometric pressure. More » Science Earth Science

Differences in temperature causing differences in air density lead to differences in air pressure. As the temperatures of portions of the atmosphere increase, the air in these portions expands and rises, causing low-pres... More »

Altitude sickness can occur following a drop in air pressure at altitudes above 8,000 feet. Altitude sickness usually only occurs when a person has not been gradually exposed or acclimatized to the low air pressure in ad... More » Health Pain & Symptoms

The ocean ecosystem, also known as the pelagic zone, is the largest collective ecosystem on Earth. Open waters have the greatest volume and depth of any living zone on the planet. The basis of ocean life is plankton, whi... More »

Jacques Piccard was an ocean explorer famous for being one of the first to venture into the Challenger Deep, the deepest part of the ocean and the lowest point on the Earth's crust. Piccard developed a specially reinforc... More » Science Earth Science

An ocean current is "any more or less permanent or continuous, directed movement of ocean water that flows in one of the Earth's oceans," according to Currents are created by a variety of forces. More »

The ocean's surface currents move warm and cold water around the world, affecting air temperature above the currents and moisture content. Surface currents have the biggest affect on the climate of coastal regions. More »