Iceland Volcano

Want to learn more about the volcano in Iceland?

Slideshow of Iceland Volcano from ABC

Winds Study Questions

1. Winds occur because the earth is heated unequally. Warmer areas have low pressure and cooler areas have high pressure. Winds occur because air will always move from areas of high pressure (more dense)to low pressure (less dense).

2. We measure wind speed with an anemometer. We measure the direction the wind is coming from with an anemometer.

3. Local winds blow over short distances. Global winds blow over long distances.

4. Sea and land breeze occur due to unequal heating of the water and the land.

During the day, the land heats faster than the water. So, the high pressure cool air over the water blows to the land (low pressure) as a sea breeze.

At night, the land cools faster than the water. So, the high pressure cool air over he land blows to the water (low pressure) as a land breeze.

5. Global winds occur because the whole earth is not heated equally by the sun so pressure differences develop. Global winds curve due to the fact that the earth is rotation--this is called the Coriolis effect.

Land and Sea Breeze Animation

Land and Sea Breeze Animation

Heat Transfer

1. Temperature is the average energy of motion of a substance. Thermal energy is the total energy of motion of a substance. So even if a tea pot and a tea cup both have the same temperature, the larger amount of tea in the tea pot has a greater thermal energy.

2. Conduction does not heat the air well. Gases (air is a mixture of gases) do not conduct heat well.

3. The troposphere is heated when heat is transferred by radiation, conduction, and convection working together. First, heat is transferred from the sun to the earth by radiation. The ground absorbs this heat and then releases some of that heat by radiation and some by conduction. This heats only the air nearest to earth's surface. The convection currents occur when the heated air near earth's surface rises, and then cools and falls. The transfer of heat by convection is what heats most of the troposphere.

More Earth Science News

A magnitude 6.9 earthquake struck western China on April 14th. So far, the death toll is estimated to be about 600, and it is belived that 10,000 people may be injured. Many unstable buildings collapsed leaving people trapped under rubble. The area where the quake occurred is difficult to access, making rescue and aid more difficult.

Watch this video about the quake.

Earth Science News

Check out this video of a volcano erupting in Iceland on March 31st. This volcano was dormant for 200 years before this eruption. Today, ariports in Northern Europe have been shut down because there is so much ash in the air due to the eruption. Do you remember why there is volcanic activity in Iceland?

Energy in Earth's Atmosphere

1. We receive electromagnetic radiation from the sun.

  • Infrared Radiation (IR) is not visible with our eyes and has a wavelength longer than that of visible light. It is felt as heat.
  • Visible Light is visible as colors. Each color of light has a different wavelength (red is the longest and violet is the shortest).
  • Ultraviolet Radiation (UV) is not visible with our eyes and has a wavelength shorter than visible light. UV radiation causes sunburn.

2. Not all sunlight makes it to earth's surface. About half of the energy from the sun is absorbed by the earth. The rest is reflected or absorbed by the atmosphere or reflected by the earth. See picture from class.

3. Scattering is when particles in the air reflect light in many directions. The short blue wavelengths of light are scattered at make the sky appear blue.

4. The greenhouse effect is when gases in the atmosphere form a blanket that traps heat around the earth. The greenhouse effect is a natural process and is needed to keep it warm enough on earth for organisms to live.

Electromagnetic Waves

Understanding electromagnetic waves can be tricky. Remember that electromagnetic waves are a type of energy, and the energy we get from the sun is an example of these waves. Electromagnetic waves are also used when you use your cellphone, listen to the radio, and cook in a microwave. Visit this NASA website to learn more about different types of electromagnetic waves.