2.1 The Earth is closest to the Sun during the: Northern Hemisphere winter Northern Hemisphere summer Southern Hemisphere spring Southern Hemisphere fall Southern Hemisphere winter

2.1 The Earth is closest to the Sun during the: Northern Hemisphere winter Northern Hemisphere summer Southern Hemisphere spring Southern Hemisphere fall Southern Hemisphere winter Earth-Sun Relationships Earth’s Motions Revolution, refers to Earth’s movement in a slightly elliptical orbit around the Sun. The distance between Earth and Sun averages about 150 million kilometers (93 million miles). Because Earth’s orbit is not perfectly circular, however, the distance varies during the course of a year. Each year, on about January 3, our planet is about 147.3 million kilometers (91.5 million miles) from the Sun, closer than at any other time—a position called perihelion. About six months later, on July 4, Earth is about 152.1 million kilometers (94.5 million miles) from the Sun, farther away than at any other time—a position called aphelion.

2.2 The motion that refers to Earth’s movement around the Sun is called Rotation Perihelion Revolution Aphelion Ecliptic

2.2 The motion that refers to Earth’s movement around the Sun is called Rotation Perihelion Revolution Aphelion Ecliptic

2.3 What is the name for the point in the Earth’s orbit where it is closest to the Sun? Perihelion Declination Zenith Sub-orbital Aphelion

2.3 What is the name for the point in the Earth’s orbit where it is closest to the Sun? Perihelion Declination Zenith Sub-orbital Aphelion Earth-Sun Relationships Earth’s Motions Revolution, refers to Earth’s movement in a slightly elliptical orbit around the Sun. The distance between Earth and Sun averages about 150 million kilometers (93 million miles). Because Earth’s orbit is not perfectly circular, however, the distance varies during the course of a year. Each year, on about January 3, our planet is about 147.3 million kilometers (91.5 million miles) from the Sun, closer than at any other time—a position called perihelion. About six months later, on July 4, Earth is about 152.1 million kilometers (94.5 million miles) from the Sun, farther away than at any other time—a position called aphelion.

2.4 The primary reason for the seasons is: Annual variations in the energy output of the Sun The Earth’s orbital tilt relative to the plane of the ecliptic The elliptical orbit of Earth Changes in the daily weather The distance of the Earth from the Sun

2.4 The primary reason for the seasons is: Annual variations in the energy output of the Sun The Earth’s orbital tilt relative to the plane of the ecliptic The elliptical orbit of Earth Changes in the daily weather The distance of the Earth from the Sun

2.5 On the Northern Hemisphere winter solstice, the noon sun has an altitude of 90° above the horizon at the: North pole Equator Tropic of Cancer Tropic of Capricorn The Arctic Circle

2.5 On the Northern Hemisphere winter solstice, the noon sun has an altitude of 90° above the horizon at the: North pole Equator Tropic of Cancer Tropic of Capricorn The Arctic Circle

2.6 Which of the following dates is closest to the Southern Hemisphere summer solstice? June 21 March 21 September 21 December 21 None of these are correct

2.6 Which of the following dates is closest to the Southern Hemisphere summer solstice? June 21 March 21 September 21 December 21 None of these are correct

2.7 Which one of the following statements is true about the equinoxes? They occur in June and December. The Sun’s vertical rays are striking either the Tropic of Cancer or the Tropic of Capricorn. Days and nights are equal in length everywhere. The length of daylight at the Arctic and Antarctic Circles is 24 hours. Both b and c are correct.

2.7 Which one of the following statements is true about the equinoxes? They occur in June and December. The Sun’s vertical rays are striking either the Tropic of Cancer or the Tropic of Capricorn. Days and nights are equal in length everywhere. The length of daylight at the Arctic and Antarctic Circles is 24 hours. Both b and c are correct.

2.8 What is the energy associated with motion called? Kinetic energy Potential energy Vibrational energy Molecular motion energy Friction

2.8 What is the energy associated with motion called? Kinetic energy Potential energy Vibrational energy Molecular motion energy Friction Energy, Temperature, and Heat Forms of Energy: Kinetic Energy Energy can be defined simply as the capacity to do work. Work is done whenever matter moves. Energy associated with an object by virtue of its motion is described as kinetic energy. A simple example of kinetic energy is the motion of a hammer when driving a nail. Because of its motion, the hammer is able to move another object (do work). The faster the hammer is swung, the greater its kinetic energy (energy of motion). Similarly, a larger (more massive) hammer possesses more kinetic energy than a smaller one, provided that both are swung at the same velocity. Likewise, the winds associated with a hurricane possess much more kinetic energy than do light, localized breezes because they are both larger in scale (cover a larger area) and travel at higher velocities.

2.9 A measure of the kinetic energy of molecules in a substance is called Melting Latent heat Heat Temperature Conduction

2.9 A measure of the kinetic energy of molecules in a substance is called Melting Latent heat Heat Temperature Conduction

2.10 The Earth receives energy from the Sun by: Convection Radiation Conduction Scattering Emissivity

2.10 The Earth receives energy from the Sun by: Convection Radiation Conduction Scattering Emissivity

2.11 Infrared radiation has a ________ wavelength than visible light. Longer Shorter Equal It is not possible to determine the wavelengths of energy.

2.11 Infrared radiation has a ________ wavelength than visible light. Longer Shorter Equal It is not possible to determine the wavelengths of energy.

2.12 The correct listing of radiation from shortest to longest wavelength is: Radio, visible, infrared, ultraviolet Infrared, visible, ultraviolet, radio Ultraviolet, visible, infrared, radio Visible, radio, ultraviolet, infrared Ultraviolet, infrared, radio, visible

2.12 The correct listing of radiation from shortest to longest wavelength is: Radio, visible, infrared, ultraviolet Infrared, visible, ultraviolet, radio Ultraviolet, visible, infrared, radio Visible, radio, ultraviolet, infrared Ultraviolet, infrared, radio, visible

2.13 The Stefan–Boltzmann Law gives the relationship between: Energy and the wavelength Emissivity and the wavelength Energy and the temperature of an object Temperature and longwave radiation Temperature and the wavelength

2.13 The Stefan–Boltzmann Law gives the relationship between: Energy and the wavelength Emissivity and the wavelength Energy and the temperature of an object Temperature and longwave radiation Temperature and the wavelength Mechanisms of Heat Transfer Laws of Radiation Hotter objects radiate more total energy per unit area than do colder objects. The Sun, which has a surface temperature of 6000 K (10,000°F), emits about 160,000 times more energy per unit area than does Earth, which has an average surface temperature of 288 K (59°F). This concept is called the Stefan–Boltzmann law.

2.14 What type of electromagnetic radiation is emitted by the Earth’s surface? Visible Microwaves Gamma rays Infrared Ultraviolet

2.14 What type of electromagnetic radiation is emitted by the Earth’s surface? Visible Microwaves Gamma rays Infrared Ultraviolet Mechanisms of Heat Transfer Laws of Radiation Hotter objects radiate more energy in the form of short-wavelength radiation than do cooler objects. We can visualize this law by imagining a piece of metal that, when heated sufficiently (as occurs in a blacksmith’s shop), produces a white glow. As it cools, the metal emits more of its energy in longer wavelengths and glows a reddish color. Eventually, no light is given off, but if you place your hand near the metal, the still longer infrared radiation will be detectable as heat. The Sun radiates maximum energy at 0.5 micrometer, which is in the visible range (Figure 2-14). The maximum radiation emitted from Earth occurs at a wavelength of 10 micrometers, well within the infrared (heat) range. Because the maximum Earth radiation is roughly 20 times longer than the maximum solar radiation, it is often referred to as longwave radiation, whereas solar radiation is called shortwave radiation.

2.15 The process by which energy passes through the atmosphere without interacting with atmospheric gases or other particles is called Reflectivity Transmission Absorption Radiation Albedo

2.15 The process by which energy passes through the atmosphere without interacting with atmospheric gases or other particles is called Reflectivity Transmission Absorption Radiation Albedo

2.16 Which one of the following is true about reflection? Light bounces back from an object at the same angle it hits the object. It causes radiation to disperse forward and backward. It causes diffused light. It can only occur because light does not travel in a straight line.

2.16 Which one of the following is true about reflection? Light bounces back from an object at the same angle it hits the object. It causes radiation to disperse forward and backward. It causes diffused light. It can only occur because light does not travel in a straight line.

2.17 On average, what percentage of solar radiation is absorbed by the Earth’s surface?

2.17 On average, what percentage of solar radiation is absorbed by the Earth’s surface? What Happens to Incoming Solar Radiation? When solar radiation strikes an object, three different things may occur: some energy may be absorbed; some energy may “bounce off” the object; and some energy may be transmitted – it is allowed to pass through without being absorbed. Figure 2-15 shows the fate of incoming solar radiation averaged for the entire globe. On average, about 50 percent of incoming solar energy is absorbed at Earth’s surface.

2.18 What is the percentage of radiation reflected by an object called? Albedo Bowen ratio Latent Scattering Emissivity

2.18 What is the percentage of radiation reflected by an object called? Albedo Bowen ratio Latent Scattering Emissivity What Happens to Incoming Solar Radiation Reflection and Scattering: Reflection and Earth’s Albedo Reflection is the process whereby light bounces back from an object at the same angle and intensity (Figure 2-16a). The fraction of radiation that is reflected by an object is called its albedo. The albedo for Earth as a whole (planetary albedo) is 30 percent.

2.19 Which of the following surfaces has the highest albedo? Forests Asphalt Sandy beach Fresh snow Plowed field

2.19 Which of the following surfaces has the highest albedo? Forests Asphalt Sandy beach Fresh snow Plowed field What Happens to Incoming Solar Radiation Reflection and Scattering: Reflection and Earth’s Albedo Figure 2-17 gives the albedos for various surfaces. Fresh snow and thick clouds have high albedos (good reflectors). By contrast, dark soils and parking lots have low albedos and thus absorb much of the radiation they receive. In general, light-colored surfaces tend to be more reflective than dark-colored surfaces and thus have higher albedos.

2.20 Which is true of solar radiation reaching the Earth’s surface? It is the primary energy input driving the Earth’s climate system. It consists of diffused solar radiation. It consists of direct solar radiation. All of these are correct. None of these are correct.

2.20 Which is true of solar radiation reaching the Earth’s surface? It is the primary energy input driving the Earth’s climate system. It consists of diffused solar radiation. It consists of direct solar radiation. All of these are correct. None of these are correct.

2.21 The two most important heat absorbing gases in the lower atmosphere are: Oxygen and nitrogen Water vapor and carbon dioxide Argon and oxygen Ozone and chlorofluorocarbons Carbon dioxide and carbon monoxide

2.21 The two most important heat absorbing gases in the lower atmosphere are: Oxygen and nitrogen Water vapor and carbon dioxide Argon and oxygen Ozone and chlorofluorocarbons Carbon dioxide and carbon monoxide

2.22 Which one of the following produces the greenhouse effect? Absorption and re-emission of visible light by the ground Absorption and re-emission of ultraviolet radiation by the atmosphere Absorption and re-emission of infrared radiation by the atmosphere Absorption and re-emission of visible light by clouds All of these are correct.

2.22 Which one of the following produces the greenhouse effect? Absorption and re-emission of visible light by the ground Absorption and re-emission of ultraviolet radiation by the atmosphere Absorption and re-emission of infrared radiation by the atmosphere Absorption and re-emission of visible light by clouds All of these are correct.

2.23 Longwave radiation arriving at the surface: Comes primarily from longwave radiation emitted by the atmosphere Comes directly from the Sun Comes from diffused solar radiation Comes from direct solar radiation Comes from ultraviolet radiation reflected from the bottom of clouds

2.23 Longwave radiation arriving at the surface: Comes primarily from longwave radiation emitted by the atmosphere Comes directly from the Sun Comes from diffused solar radiation Comes from direct solar radiation Comes from ultraviolet radiation reflected from the bottom of clouds

2.24 The annual balance of Earth’s incoming and outgoing radiation and the energy balance between the surface and atmosphere is called Earth’s energy budget Albedo Greenhouse effect Radiative cooling Absorption

2.24 The annual balance of Earth’s incoming and outgoing radiation and the energy balance between the surface and atmosphere is called Earth’s energy budget Albedo Greenhouse effect Radiative cooling Absorption