10.1 TEMPERATURE, THERMAL ENERGY AND HEAT Name: Date: Block: (Reference: pp of BC Science 10)

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1 10.1 TEMPERATURE, THERMAL ENERGY AND HEAT Name: Date: Block: (Reference: pp of BC Science 10) kinetic molecular theory: explains that matter is made up of tiny that are constantly. These atoms and molecules are constantly in motion. kinetic energy: The particles of a substance move differently for different states. In solids, particles slightly, but do not change position. In liquids, particles vibrate, past each other, shape depends on, move around a volume. In gases, particles vibrate, move around to all volume available. TEMPERATURE Temperature: The movement of particles is what we measure as temperature. Three different temperature scales are used to measure temperature:, and.

2 THERMAL ENERGY Thermal energy: Thermal energy = all kinetic energy + all potential energy potential energy: = how much the particles vibrate, and therefore how much space they take up. HEAT Heat: HEAT TRANSFER Heat transfer can occur in ways:

3 1. Conduction: Heat is transferred from temperature, kinetic energy, of particles to temperature, where particles have kinetic energy. Ex. a cold spoon warms when placed in a cup of hot coffee. transfer heat easily, while do not. 2. Convection: Fluids: Ex. Melted rock under the Earth s surface and clouds in the sky move by convection. Convection is the movement of heat from to within a fluid, or the movement of liquid to an area of liquid. Because there is a difference, hot fluid ( density) moves to cold. This is how convection currents form. Convection current:

4 3. Radiation: electromagnetic radiation: infrared radiation (aka heat radiation): solar radiation: made up of visible light and infrared radiation. 3 sources of thermal energy on Earth: 1. accounts for much of the thermal energy at Earth s surface. Earth s interior thermal energy comes from: 2. the core (where residual energy from the of the Earth continues to be released), 3. the decay of underground. Complete p. 435 #1-10

5 10.2 ENERGY TRANSFER IN THE ATMOSPHERE Name: Date: Block: (Reference: pp of BC Science 10) Earth s is a key factor in allowing life to survive here. This band of air has the right and maintains the correct, to allow life to form and survive. Originally, Earth s atmosphere was very different and had no. Scientists think that oxygen first came from the breakdown of water by, then later from by plants. The composition of Earth s atmosphere. What we call air is a combination of gases in the atmosphere, near Earth s surface. The two main gases in the lower atmosphere are and (about 99%). The composition of the atmosphere remains constant up to a height of about km above sea level. The density of the atmosphere with altitude.

6 THE LAYERS OF THE ATMOSPHERE Earth s atmosphere is made up of layers: : closest to Earth s surface; km to km thick density layer because all other layers compress it. Almost all in the atmosphere is found here. Therefore, this is where most takes place. Solar energy and thermal energy from Earth keep air moving Temperatures range from average of + ºC at the bottom to ºC at the top. 2. : the second layer, above the troposphere; km to km above Earth, Warming from ºC as altitude increases

7 The air is cold, dry, and clean in the stratosphere. Strong, steady winds, often fly here to avoid turbulent troposphere. The layer is found here, which blocks harmful UV radiation. The remaining three layers are known as the atmosphere. 3. : km to km above Earth Temperatures are as low as ºC This layer is where burns up when it begins to hit particles. 4. : km to km above Earth Temperatures can reach + ºC to + ºC This is where the, aurora borealis, are found. Charged particles in Earth s collide with particles in the thermosphere. 5. : km to km above Earth where the atmosphere merges with.

8 RADIATION AND CONDUCTION IN THE ATMOSPHERE Almost all of the thermal energy on Earth comes from the. Yet, this is only a small fraction of the solar radiation that Earth. Most thermal energy is transferred near the, which receives a more direct source of solar radiation. Insolation: Insolation if there are particles of matter (dust, smoke) in the way or if the angle of incidence of the solar radiation is too great. angle of incidence: Solar radiation does not heat the atmosphere. Earth s surface solar radiation, heats up, then the thermal energy into the atmosphere. This provides percent of the air s thermal energy. in the air spread the thermal energy around.

9 THE RADIATION BUDGET AND ALBEDO The radiation budget is used to explain If all 342 W/m 2 of solar radiation that reaches Earth was stored in the atmosphere, it would be far too hot to support life as we know it. Earth s radiation budget = heat heat Of the of the solar radiation that reaches Earth, percent is reflected by clouds back into space, percent is reflected by particles back into space, percent is absorbed by clouds and the atmosphere, and percent reaches Earth s surface percent of this amount is reflected back out into space by Earth s surface percent drives the water cycle, percent creates wind, and percent is re-radiated from Earth s surface.

10 Albedo: Light-coloured surfaces (snow, sand) have a albedo and energy. Dark-coloured surfaces (soil, water) have a albedo and energy. WHAT IS WEATHER? weather: Weather describes all aspects of the atmosphere and is closely related to the transfer of thermal energy. ATMOSPHERIC PRESSURE force: Ex. The force of gravity pulls you to the ground. pressure: atmospheric pressure (aka air pressure): measured with a SI Unit: ( ) Used to measure the vertical force per unit area. 1 Pa = A small amount so most measurements given in ( ).

11 THREE FACTORS THAT AFFECT ATMOSPHERIC PRESSURE 1. Altitude At sea level, atmospheric pressure = (equal to kpa) As you increase altitude, the density of air, therefore the atmospheric pressure (fewer particles means fewer collisions). On average, the atmospheric pressure at the top of the troposphere is only about percent of that at sea level. However, pressure differences throughout the troposphere because of the of air. Our bodies equalize pressure = why our ears with pressure change. 2. Temperature Warm air is dense and than cool air and so warm air has a pressure than cool air.

12 The movement of air at different temperatures also affects atmospheric pressure. When warm air pushes into an area of cold air near the ground, the atmospheric pressure in that area. When cold air pushes into an area of warm air, the atmospheric pressure in that area. 3. Humidity Humidity: Humid air (air with water vapour) is and has pressure than dry air. As the amount of water vapour increases in a region of the atmosphere, it an equal volume of dry air (mostly nitrogen and oxygen). Water vapour is lighter than nitrogen and oxygen gas, so the air will become. This makes humid air exert pressure than dry air. Meteorologists use atmospheric pressure readings to predict the. A decrease in atmospheric pressure suggests that, air is coming and that the temperature will.

13 An increase in atmospheric pressure suggests that, weather is on its way. Specific humidity: Equal to the number of grams of water vapour in 1 kg (or 1 m 3 ) of air. As the temperature of air increases it can hold water vapour. Dew point: when the specific humidity the capacity of air to hold water at a specific temperature. Relative humidity: 45 percent relative humidity means that the air is holding percent of the water vapour it could before reaching its. CONVECTION IN THE ATMOSPHERE Wind: air mass: Air masses take on the conditions of the below. Air masses can be several thousand kilometres wide and several kilometres thick.

14 High pressure systems High pressure systems form when an air mass. usually form over water or land. As the air masses cool, they become, and draw in more air from the upper troposphere, increasing the atmospheric pressure. The dense, high pressure air moves out toward areas of low pressure, creating wind. Winds blow around the centre of the system in the northern hemisphere, counterclockwise in the southern hemisphere. As air sinks it becomes more dense and warmer, so it can hold more water vapour than in the atmosphere. Air becomes and. skies Low pressure systems Low pressure systems form when an air mass. usually occurs over water or land. Air mass warms, expands, becoming dense and. It cools as it rises, causing water vapour to condense and form or. The expanding air mass pushes away air in the upper troposphere, causing atmospheric pressure below to drop, and draw in surrounding higher pressure air. Winds blow around the centre of the system in the northern hemisphere and clockwise in the southern hemisphere due to Earth s.

15 PREVAILING WINDS Prevailing winds: Ex. In southern British Columbia -> moist air masses from the Pacific Ocean blows inland over the coastal mountains. falls as air is forced up the mountain slopes. Air gets as it moves inland, continuing to drop precipitation. air rushes down the far side of the mountains into the prairies. Local winds sea breezes: Daytime -> land faster than nearby water body. Air above the land heats up and rises, causing cool air from over the ocean to be drawn in to replace it. creates an. Night -> land faster than nearby water body. Air over water warms and rises, causing cool air from over the land to be drawn out to replace it. creates an.

16 THE CORIOLIS EFFECT Winds move from pressure to pressure. If the Earth was 1/6 its size, air would warm in the tropics and rise. Cooler air from the north would rush in below to fill the empty spot. The warm air at higher altitudes would move north to replace the cooler air. Due to Earth s actual size, as it rotates, air long before it reaches the. Over long distances winds are bent clockwise due to the of the Earth. Coriolis effect: Because the equator moves much more than do the poles. Deflects winds to the in the northern hemisphere, and to the in the southern hemisphere. Global wind systems wind systems: Earth has three major wind systems: 1. The : from east to west 2. The : from west to east 3. The : flow east to west due to the Coriolis effect

17 JET STREAMS jet stream: Flow west to east due to the Earth s rotation. try to fly with these winds. jet stream and jet stream are two major jets streams over North America. Produced by convection currents in the atmosphere, and affected by temperature differences in the atmosphere. Cooler times = jet stream and to the equator. Affect the movement of air beneath them so can affect the. FRONTS front: indicated by a band of an approaching front means a in weather. cold air forces warm air to rise, so fronts usually bring. Four types of fronts and weather map symbols: Cold front

18 EXTREME WEATHER Air masses often have very large amounts of energy. Extreme weather can arise under certain conditions as this energy is. Three types of extreme weather: 1. Thunderstorms: Produces large (cumulonimbus clouds) can reach the top of the troposphere and form an shape. Static energy can be built up and released as. Sea breezes in the tropics and energetic cold (and even warm) fronts can cause thunderstorms. 2. Tornadoes: form when high-altitude fast horizontal winds meet large thunderstorms and produce a spinning vortex of air called a funnel cloud that touches the ground. When tornadoes form over water, they can form (funnel-shaped columns of water). 3. Tropical cyclones, typhoons, and hurricanes: Large masses of warm, moist air rise quickly and cool air rushes in. Air rotates in the northern Complete p. 459 #1-19 hemisphere, in the south.