Chapter 2 Solar Energy to Earth and the Seasons Essay Questions

2.3 Essay Questions 1) Why is the light year a useful unit of measurement for astronomical distances? Answer: The size of the universe is vast; the light year is therefore a useful unit of measurement for distances of such galactic scale. Diff: 3 Type: ES Chapter/section: 2.1 The Solar System, Sun, and Earth Bloom's Taxonomy: 5/6 Synthesis/Evaluation LO: 2.7 Explain the characteristics of the electromagnetic spectrum of radiant energy. 2) Describe the causes and consequences of the uneven distribution of insolation. Answer: Due to the curved surface of Earth, lower latitudes receive more concentrated direct insolation, while higher latitudes receive less concentrated, more diffuse insolation. This latitudinal imbalance in energy drives global circulation in the atmosphere and oceans. Diff: 3 Type: ES Chapter/section: 2.2 Solar Energy: From Sun to Earth Bloom's Taxonomy: 5/6 Synthesis/Evaluation LO: 2.8 Illustrate the interception of solar energy and its uneven distribution at the top of the atmosphere. 3) Describe the radiation emitted from both the Sun and Earth in terms of the electromagnetic spectrum. Answer: The sun emits shortwave radiation primarily in the visible and infrared wavelengths, while Earth emits longwave radiation primarily in the thermal infrared wavelengths. Diff: 3 Type: ES Chapter/section: 2.2 Solar Energy: From Sun to Earth Bloom's Taxonomy: 5/6 Synthesis/Evaluation LO: 2.7 Explain the characteristics of the electromagnetic spectrum of radiant energy. 4) How does the daily insolation received at the top of the atmosphere vary annual from lower to higher latitudes? Answer: At lower latitudes, daily insolation is high throughout the year, with little variation month to month. At higher latitudes, insolation values are greatest in the summer months, lowest in the winter months, and vary greatly with latitude. Diff: 3 Type: ES Chapter/section: 2.2 Solar Energy: From Sun to Earth Bloom's Taxonomy: 5/6 Synthesis/Evaluation LO: 2.8 Illustrate the interception of solar energy and its uneven distribution at the top of the atmosphere. 84 5) Define these terms: thermopause, insolation, solar constant, subsolar point. Answer: Thermopause: outer boundary of the energy system of Earth, the region at the top of the atmosphere (approx. 480 km); insolation: incoming solar radiation; solar constant: average insolation received at the thermopause when Earth is at its average distance from the Sun (1372 W • m-2); Subsolar point: the only point where insolation arrives perpendicular to the surface. Diff: 3 Type: ES Chapter/section: 2.2 Solar Energy: From Sun to Earth Bloom's Taxonomy: 5/6 Synthesis/Evaluation LO: 2.9 Define solar altitude, solar declination, and daylength. 6) Explain the significance of each of the equinoxes and solstices. Answer: The equinoxes mark the beginning of the spring and fall, all locations on Earth between the poles have equal daylengths; and it marks the sunrise/set at the poles. The solstices that mark the beginning of the summer and winter, occur when the subsolar point is at its maximum latitude; and when either the Arctic (June solstice) or Antarctic (December Solstice) Circles are completely within the circle of illumination. Diff: 3 Type: ES Chapter/section: 2.2 Solar Energy: From Sun to Earth Bloom's Taxonomy: 5/6 Synthesis/Evaluation LO: 2.10 Describe the annual variability of solar altitude, solar declination, and daylength— Earth's seasonality. 7) What primary factors determine the seasons on Earth? Answer: Revolution of Earth around the Sun; rotation of Earth on its axis; Earth's axial tilt; axial parallelism; and sphericity of Earth. Diff: 3 Type: ES Chapter/section: 2.3 The Seasons Bloom's Taxonomy: 5/6 Synthesis/Evaluation LO: 2.10 Describe the annual variability of solar altitude, solar declination, and daylength— Earth's seasonality. 8) What is the circle of illumination and why is it important? Answer: The circle of illumination is the dividing line between day and night. Combined with the four factors that cause the seasons, the circle of illumination will influence daylength throughout the year. Diff: 3 Type: ES Chapter/section: 2.3 The Seasons Bloom's Taxonomy: 5/6 Synthesis/Evaluation LO: 2.10 Describe the annual variability of solar altitude, solar declination, and daylength— Earth's seasonality. 9) For where you live, how do daylength and the altitude of the Sun vary throughout the year? Answer: Answers will vary depending on where students live. Diff: 3 Type: ES Chapter/section: 2.3 The Seasons Bloom's Taxonomy: 5/6 Synthesis/Evaluation LO: 2.9 Define solar altitude, solar declination, and daylength. 85 10) Why are seasonal changes less noticeable near the equator than at mid-latitudes? Answer: Because the equatorial region receives fairly constant high insolation and has consistent daylength throughout the year, there is little seasonal variation; at the midlatitudes,insolation varies throughout the year (as does daylength), there are greater seasonal variations. Diff: 3 Type: ES Chapter/section: 2.3 The Seasons Bloom's Taxonomy: 5/6 Synthesis/Evaluation LO: 2.10 Describe the annual variability of solar altitude, solar declination, and daylength— Earth's seasonality. 11) Draw and label a diagram of the Earth-Sun relationship for the four seasons. Include the average distance from Earth to the Sun, the location of the subsolar point for each seasonal event, and the name and date for each of the solstices and equinoxes. Answer: Answers will vary. Figure GIA 2.1 is a good basis for the answer. Diff: 3 Type: ES Chapter/section: 2.3 The Seasons Bloom's Taxonomy: 5/6 Synthesis/Evaluation LO: 2.10 Describe the annual variability of solar altitude, solar declination, and daylength— Earth's seasonality. 12) Discuss ways in which anthropogenic climate change affects seasonality. Answer: There are several examples given in the book, but students can select others, as well. Seasonal shifts in the subtropical high pressure zone in Africa are leading to decreased rainfall; in the Canada and the United States, the trend has been towards a longer growing season; and in the far north, longer summers have changed migration patterns of moose. Diff: 3 Type: ES Chapter/section: 2.4 The Human Denominator Bloom's Taxonomy: 5/6 Synthesis/Evaluation LO: 2.10 Describe the annual variability of solar altitude, solar declination, and daylength— Earth's seasonality. 86