The atmosphere is the envelope of gases surrounding a celestial body, such as a planet or moon. On Earth, the atmosphere is composed mainly of nitrogen (about 78%), oxygen (about 21%), and trace amounts of other gases such as carbon dioxide, water vapor, and noble gases.

Atmosphere

The hydrosphere refers to the total amount of water on a planet, including all forms of water such as liquid, solid (ice), and gas (water vapor). On Earth, the hydrosphere encompasses all bodies of water, from oceans, seas, and lakes to rivers, groundwater, and glaciers.

Hydrosphere

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The Atmosphere

The blanket of gas that protects us.

On Earth, the atmosphere is composed mainly of nitrogen (about 78%), oxygen (about 21%), and trace amounts of other gases such as carbon dioxide, water vapor, and noble gases.

The troposphere is the layer of the atmosphere closest to the Earth's surface, extending from the surface to an average altitude of about 8 to 15 kilometers (5 to 9 miles) depending on location and weather conditions.

Troposphere

The stratosphere contains the ozone layer, a region with a higher concentration of ozone molecules that absorb and scatter ultraviolet (UV) radiation from the sun.

Stratosphere

The mesosphere is where meteors burn up upon entry into Earth's atmosphere, creating the phenomenon known as "shooting stars."

Mesosphere

The thermosphere experiences extremely high temperatures, reaching thousands of degrees Celsius, despite the low density of particles.

Thermosphere

The Hydrosphere

Also known at the water cycle or the hydrological cycle.

On Earth, the hydrosphere encompasses all bodies of water, from oceans, seas, and lakes to rivers, groundwater, and glaciers.

The process by which liquid water is transformed into water vapor (a gas) due to the input of heat energy from the sun.

Evaporation

The reverse process of evaporation. It involves the conversion of water vapor into liquid water as it loses heat energy.

Condensation

Refers to any form of water - liquid or solid - that falls from the atmosphere to the Earth's surface

Preciptation

The release of water vapor from plants into the atmosphere.

Transpiration

Also known at the water cycle or the hydrological cycle, it's all the water on Earth.

Hydrosphere

The blanket of gas that protects us.

Atmosphere

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