Science Curriculum Topic Study

Air & Atmosphere and Weather & Climate

V. Examine Coherency and Articulation

Atlas of Science Literacy, Volume 2

• Temperature and Winds
• K-2: The sun warms the land, air, and water
• 3-5: A warmer object can warm a cooler one by contact or at a distance. When warmer things are put with cooler ones, heat is transferred from the warmer ones to the cooler ones.
• 6-8: Light and other electromagnetic waves can warm objects. How much an object’s temperature increases depends on how intense the light striking its surface is, how long the light shines on the object, and how much of the light is absorbed. The temperature of a place on the earth’s surface tends to rise and fall in a somewhat predictable pattern every day and over the course of a year. The pattern of temperature changes observed in a place tend to vary depending on how far north or south of the equator the place is, how near to the oceans it is, and how high above sea level it is. The number of hours of daylight and the intensity of the sunlight both vary in a predictable pattern that depends on how far north or south of the equator the place its. This variation explains why temperatures vary over the course of the year and at different locations. Thermal energy is transferred through a material by collisions of atoms within the material. Over time, the thermal energy tends to spread out through a material and from one material to another if they are in contact. Thermal energy can also be transferred by means of currents in air, water, or other fluids. In addition, some thermal energy in all materials is transformed into light energy and radiated into the environment by electromagnetic waves; that light energy can be transformed back into thermal energy when the electromagnetic waves strike another material. As a result, a material tends to cool down unless some other form of energy is converted to thermal energy into the materials. Thermal energy carried by ocean currents has a strong influence on climates around the world. Areas near oceans tend to have more moderate temperatures than they would if they were farther inland but at the same latitude because water in the oceans can hold a large amount of thermal energy.
• 9-12: Because the earth turns daily on an axis that is tilted relative to the plane of the earth’s yearly orbit around the sun, sunlight falls more intensely on different parts of the earth during the year. The difference in intensity of sunlight and the resulting warming of the earth’s surface produces the seasonal variations in temperature. In a fluid, regions that have different temperatures have different densities. The action of a gravitational force on regions of different densities causes them to rise or fall creating currents that contribute to the transfer of energy. Transfer of thermal energy between the atmosphere and the land or oceans produces temperature gradients in the atmosphere and the oceans. Regions at different temperatures rise or sink or mix, resulting in winds and ocean currents. These winds and ocean currents, which are also affected by the earth’s rotation and the shape of the land, carry thermal energy from warm to cool areas.
• Water Cycle
• K-2: Water can be a liquid or a solid and go back and forth from one form to the other. If water is turned into ice and then the ice is allowed to melt, the amount of water is the same as it was before freezing. Water left in an open container disappears, but water in a closed container does not disappear.
• 3-5: When liquid water disappears, it turns into a gas (vapor) in the air and can reappear as a liquid when cooled, or as a solid if cooled below the freezing point of water. Clouds and fog are made of tiny droplets or frozen crystals of water.
• 6-8:Water evaporates from the surface of the earth, rises and cools, condenses into rain or snow, and falls again to the surface. The water falling on land collects in rivers and lakes, soil, and porous layers of rock, and much of it flows back into the oceans. The cycling of water in and out of the atmosphere is a significant aspect of the weather patterns on earth.
• 9-12: Life is adapted to conditions on the earth, including the force of gravity that enables the planet to retain an adequate atmosphere, and an intensity of electromagnetic waves from the sun that allows water to be present in the liquid state.
• Atmosphere
• K-2: The temperature and amount of rain (or snow) tend to be high, low, or medium in the same months every year.
• 3-5: Air is a material that surrounds us and takes up space and whose movement we feel as wind. The weather is always changing ad can be described by measurable quantities such as temperature, wind direction and speed, and precipitation. Large masses of air with certain properties move across the surface of the earth. The movement and interaction of these air masses is used to forecast the weather.
• 6-8: The earth is mostly rock. Three-fourths of the earth’s surface is covered by a relatively thin layer of water (some of it frozen), and the entire planet is surrounded by a relatively thin layer of air. The earth has a variety of climates, defined by average temperature, precipitation, humidity, air pressure, and wind, over time in a particular place. The atmosphere is a mixture of nitrogen, oxygen, and trace amounts of water vapor, carbon dioxide, and other gases.
• 9-12: Plants on land and under water alter the earth’s atmosphere by removing carbon dioxide from it, using the carbon to make sugars and releasing oxygen. This process is responsible for the oxygen content of the air. Climatic conditions result from latitude, altitude, and from the position of mountain ranges, oceans, and lakes. Dynamic processes, such as cloud formation, ocean currents, and atmospheric circulation patterns influence climates as well.

• Climate Change
• K-2: Change is something that happens to many things.
• 3-5: No benchmarks listed
• 6-8: Human activities, such as reducing the amount of forest cover, increasing the amount and variety of chemicals released into the atmosphere, and intensive farming, have changed the earth’s land, oceans, and atmosphere. Some of these changes have decreased the capacity of the environment to support some life forms. Climates have sometimes changed abruptly in the past as a result of volcanic eruptions or impacts of huge rocks from space.
• 9-12: Greenhouse gasses in the atmosphere, such as carbon dioxide and water vapor, are transparent to much of the incoming sunlight but not to the infrared light from the warmed surface of the earth. When greenhouse gasses increase, more thermal energy is trapped in the atmosphere, and the temperature of the earth increases the light energy radiated into space until it again equals the light energy absorbed from the sun. The earth’s climates have changed in the past, are currently changing, and are expected to change in the future, primarily due to changes in the amount of light reaching places on the earth and the composition of the atmosphere. The burning of fossil fuels in the last century has increased the amount of greenhouse gases in the atmosphere, which has contributed to earth’s warming.

Resources:

§ American Association for the Advancement of Science. 2007. Atlas for Science Literacy. Volume 2. Washington, DC: NSTA Press.

§ Keeley, P. 2005. Science Curriculum Topic Study: Bridging the Gap Between Standards and Practice. Thousand Oaks, CA: Corwin Press.