Our World: What is Weather? video: This NASA video segment focuses on the relationship between weather and climate. Learn how heat, air pressure, winds and moisture work together to produce local weather.
Science Is Elementary: What in the World? The Earth Explained: Weather and Climate video: (Note: To view this video you must have a Discovery Education account) In this video, we learn that weather is the condition of the atmosphere in terms of heat, air pressure, wind, and moisture that changes almost daily, whereas climate is the long-term weather in a certain area. The concepts of water vapor, evaporation, condensation, and precipitation are introduced in a discussion of the water cycle. The different layers of the atmosphere are named and discussed, as is the role of the sun in providing heat energy to warm the earth and its atmosphere. Wind, air masses, fronts, storms and other weather phenomena are described, as are hurricanes and tornados. The video concludes with a brief reference to instruments used to measure various aspects of weather.
- Air Pressure: The weight per unit of area of a column of air that reaches to the top of the atmosphere.
Context: Areas of high air pressure, or high-pressure systems, usually have clear skies, and areas of low air pressure, or low-pressure systems, usually have clouds.
- Atmosphere: The layer of air that surrounds Earth and is made up of nitrogen (about 78 percent), oxygen (about 21 percent), and miscellaneous gases (about 1 percent).
Context: Our weather takes place in the lower part of the atmosphere.
- Front: A narrow zone of transition between air masses that differ in temperature or humidity.
Context: Most changes in the weather occur along fronts.
- Humidity: A measure of the amount of moisture in the air in the form of invisible water vapor.
Context: Humidity is important for making weather forecasts, because it can help scientists predict precipitation.
- Meteorologist: A scientist who studies the weather.
Context: Meteorologists use different types of maps to report the weather.
- Precipitation: Moisture that falls from clouds in the form of rain, snow, sleet, or hail.
Context: Without rain or other forms of precipitation, the ground becomes dry, and crops cannot grow.
- Temperature: The measure of the heat energy of the gases in the air.
Context: Changes in temperature lead to changes in air pressure, bringing different kinds of weather.
- Weather: The state of the atmosphere at a given time in a particular place.
Context: The three main factors of weather are humidity, air pressure, and temperature.
- Wind: The movement of air, which tends to move from a high-pressure area to a low-pressure area.
Context: Winds are named for the direction from which they blow, so an easterly wind blows from the east.