Earth's Water

Air front

The boundary between two air masses of different temperatures is called an air front. An air front is where two different air masses meet, often causing changes in weather.

Air mass

A huge body of air with similar temperature and moisture throughout. Air mass. An air mass is a large volume of air in the atmosphere that has uniform temperature and moisture.

Air pressure

The weight of the air pressing down on a surface. Air pressure. Air pressure is the force exerted by the weight of air molecules on a surface.

Anemometer

An instrument that measures wind speed. Anemometer. An anemometer is a device used to measure how fast the wind is blowing.

Atmosphere

The layer of gases that surround the Earth. atmosphere. The atmosphere is a mix of gases like oxygen and nitrogen that surrounds our planet, protecting life and helping regulate temperature.

Barometer

An instrument that measures air pressure. Barometer. A barometer is a tool used to determine atmospheric pressure, helping forecast weather changes.

Climate

The average weather conditions of an area, over a long period of time. Climate. Climate is what you expect in terms of weather patterns over many years in a specific region.

Cold front

The boundary of a mass of cold air where it slides under a mass of warm air. Cold front. A cold front is when cold air moves in and pushes warm air upward, often causing weather changes like rain or thunderstorms.

Condensation

The process of a gas changing into a liquid. Condensation. Condensation is when water vapor in the air cools down and turns back into droplets, like on a cold glass.

Evaporation

The top of liquid changing into a gas. Evaporation. Evaporation is when a liquid turns into a gas, usually from the surface, when heat causes its molecules to move faster and break away.

Greenhouse effect

The warming of the Earth when the atmosphere traps heat like a blanket. Greenhouse effect. It is a process where certain gases in Earth's atmosphere trap heat, keeping the planet warmer.

Humidity

The amount of water vapor in the air humidity. Humidity is how much moisture is present in the air around us.

Hurricane

A large tropical storm with winds of more than 74 mph. Hurricane. A hurricane is a powerful storm system with strong winds and heavy rain that forms over warm ocean waters.

Precipitation

Water that falls to Earth in any form, like rain, snow, sleet, or hail. Precipitation. Precipitation is when water from clouds falls to the ground as rain, snow, or ice.

Tornado

A spinning funnel-shaped column of wind. Tornado. A tornado is a powerful rotating storm that extends from a thunderstorm cloud down to the ground, causing intense wind and damage.

Warm front

The boundary where a warm air mass moves over a cold air mass. Warm front. A warm front is when warmer air gradually slides over colder air, bringing gradual weather changes like light rain or milder temperatures.

Water cycle

The constant movement of water through Earth and its atmosphere, by evaporation, condensation, and precipitation. Water cycle. The water cycle is the journey water takes as it changes form and moves from the ground to the sky and back again.

Weather

The atmospheric conditions at a specific time and place, like raining and cold. Weather. Weather is the state of the atmosphere at a particular time and place, including temperature, humidity, wind, and precipitation.