GEO 11 Support Pack for The atmosphere geographica

Study & Master Support Pack | Grade 11 CAPS Geography The atmosphere – geographical knowledge This support pack for the The atmosphere – geographical knowledge module in the Geography Grade 11 CAPS curriculum provides valuable revision activities. All activities have the answers provided. Learners can work through these individually at home or these could form the basis of a catch-up class or online lesson. You have permission to print or photocopy this document or distribute it electronically via email or WhatsApp. For more information on our Study & Master CAPS-approved  textbooks and valuable resource materials, visit www.cambridge.org Brighter Thinking | Better Learning

The atmosphere – geographical knowledge QUESTION 1 QUESTION 2 Choose the correct underlined word/words for each Look at Figures 1 and 2. There are symbols and letters statement. Write down the question number on the diagram, but few labels. Provide labels for the and the underlined word/words only. following by thinking and reasoning as to what is 1. Weather generally changes on a daily/annual/ happening in the diagram. decadal/millennial basis. 1. What does the circular arrow at the top of the 2. Insolation stands for incoming Sun rays/incumbent diagram represent? solar re-radiation/incoming solar radiation/inward 2. a) What do the letters H stand for? solar refraction. b) What do the letters L stand for? 3. Ocean currents transfer water and energy/air and c) What do the letters PGF stand for? energy/air and water/energy and radiation. 3. Why are the wind arrows deflected, rather than 4. The climate classification we still use today was being straight? devised over a hundred years ago by Sigmund 4. What do the values 0º, 30º and 60º represent? Freud/Albert Einstein/Walter Scott/Wladimir 5. Explain the term Intertropical Convergence Zone Köppen. (ITCZ) by breaking down these words to form a 5. The Spanish term for a reversal in Pacific ocean- simpler meaning. [8] atmosphere circulation is El Toro/El Paso/ El Niño/La Bianca.(5×2) [10] 60° L subpolar low L PGF wind 30° H subtropical high H wind PGF 0° L Intertropical Convergence Zone (ITCZ) L wind PGF 30° H subtropical high H PGF wind 60° L subpolar low L Figure 1 A simple, unicellular (one cell for each hemisphere) Figure 2 A simplified representation of the Earth’s atmospheric circulation pattern, which would move heat pressure belts energy from the equator towards the poles if the Earth did not rotate on its axis S T U DY & M A S T E R T h e a t m o s p h e r e – g e o g r a p h i c a l k n ow l e d g e 1

QUESTION 3 3. List the low-latitude climates that are dominated Choose whether the statement is True or False. Write by tropical air masses and have consistent weather down the question number and ‘T’ or ‘F’ only. patterns. 1. A front separates two air masses. 4. List the mid-latitude climates that are affected by 2. The ITCZ separates polar air masses. two conflicting air masses – tropical and polar – 3. Coriolis force causes the Earth to rotate. and have changeable weather. 4. Pressure gradient force will oblige air to move 5. Apply Köppen’s climate classification system and from a high- to a low-pressure zone. the climate region/biome subgroups to each of the 5. Drought and desertification are not the same climate regions in Figure 3. Use the three climate thing.  (5×1) types A–C: A – Tropical humid; B – Dry; C – Mild [5] mid-latitude and these climate region subgroup QUESTION 4 codes: Match the statement in Column B of the table with the f – moist, with plenty of rain throughout the year word or phrase in Column A. m – rainforest climate, but short, dry monsoon cycle season Column A Column B s – dry summer season 1. Coriolis force A. geostrophic winds occur here w – dry winter season 2. geostrophic wind B. drag between two things along (For example, the code for tropical seasonal/ a plane separating them monsoon rainforest is Am.) [10] 3. pressure gradient C. unit of atmospheric pressure force 4. wind D. deflection caused by Earth’s 400 rotation 5. isobar E. blows parallel to isobars tropical 300 rainforest 6. millibar F. imaginary line joining points of Annual rainfall (cm) equal pressure 7. upper atmosphere G. the cause of wind 200 tropical 8. friction H. moving air seasonal forest 9. hemisphere I. divides Earth into two temperate hemispheres 100 grassland and desert savanna 10. equator J. half a sphere subtropical desert 0 QUESTION 5 30 20 10 0 -10 Average temperature (°C) Explain what geostrophic flow is, and what causes it. [10] Figure 3 Africa’s climate regions plotted as temperature versus rainfall QUESTION 6 Briefly explain how air convergence, rising and QUESTION 8 subsidence are linked to global precipitation Define: patterns.  [10] 1. rainfall variability 2. monsoon conditions QUESTION 7 3. semi-arid Refer to Figure 3 and answer the following questions. 4. Föhn wind 1. Identify the climate region with: 5. savanna(5×2) a) the highest temperatures and rainfall [10] b) the lowest temperatures and rainfall. 2. Which group(s) does the semi-arid region belong to? 2 S T U DY & M A S T E R S U P P O R T PA C K

QUESTION 9 QUESTION 10 Give the opposite, or opposite term, for each of the Refer to the synoptic maps in Figures 5 and 6 on following as they are used in climatology: pages 5 and 6, and the weather symbols in Figure 4 1. high pressure and answer the questions. 2. arid 1. Why are some station models shown as triangles? 3. tropical or equatorial 2. Compare the temperatures on the two maps in 4. drought general, and Upington and Pretoria specifically. 5. cause(5×1) 3. Give the summer and winter temperatures and [5] calculate the differences in each case for: a) Walvis Bay b) Windhoek. 4. Find the high-pressure cell to the west of southern Africa in the summer map. a) Name the pressure belt it belongs to. b) Explain what has happened to this high- pressure cell in the winter map, and why this has happened.  [12] [Total: 90 marks] WEATHER CLOUD COVER WIND SPEED in eighths of sky covered rain none calm 2–4 km/h drizzle 1 9 km/h showers 19 km/h 2 28 km/h snow 37 km/h 3 hail 46 km/h 56 km/h 4 fog 93 km/h 5 120 km/h duststorm 1,0 km/h = 0,54 knots thunderstorm 6 cold front thunderstorm with hail 7 warm front weather for preceding hour but not at time 8 occluded front of observation Figure 4 Universal weather symbols are also used on South African synoptic weather maps. Note that the South African Weather Service prefers to use knots for wind speed, but wind speeds are shown above in km/h to make them more meaningful. S T U DY & M A S T E R T h e a t m o s p h e r e – g e o g r a p h i c a l k n ow l e d g e 3

Figure 5 A synoptic map of typical summer conditions over southern Africa 4 S T U DY & M A S T E R S U P P O R T PA C K

Figure 6 A synoptic map of typical winter conditions over southern Africa; note the strongly developed cold front. S T U DY & M A S T E R T h e a t m o s p h e r e – g e o g r a p h i c a l k n ow l e d g e 5

Answers QUESTION 1 QUESTION 5 1. daily ✓✓ With geostrophic flow, air starts to move, under 2. incoming solar radiation ✓✓ pressure gradient force, ✓ at right angles to the isobars 3. water and energy ✓✓ from high (H) to low (L). ✓ As soon as this movement 4. Wladimir Köppen ✓✓ starts, the wind comes under the influence of Coriolis 5. El Niño ✓✓ (5×2) force, ✓ which causes it to deviate from its path. ✓ [10] Note how the influence of Coriolis force becomes QUESTION 2 greater. ✓ Eventually, a situation is reached where the 1. rotation of the Earth on its central axis ✓ wind is blowing parallel to the isobars, ✓ and pressure 2. a) high pressure ✓ gradient and Coriolis force balance each other. ✓ b) low pressure ✓ This wind blowing parallel to the isobars is called a c) pressure gradient force ✓ geostrophic wind. ✓ Geostrophic winds blow in the 3. because of Coriolis force, which causes moving air upper atmosphere, ✓ where there is little or no to deflect from a straight path ✓ friction or drag between the moving air and the 4. lines of latitude, with 0° being the equator. ✓ Earth’s surface. ✓ [10] 5. Inter = between and ‘tropical’ is the hot equatorial regions. Convergence = to come together. QUESTION 6 Zone = an area. So, the ITCZ is the area in the Subsiding air is moving from the upper tropical regions where air masses come together. atmosphere towards the Earth’s surface. ✓ Rising The air is then forced to rise, and thunderstorms air is moving from the Earth’s surface towards the result. ✓✓ [8] upper atmosphere. ✓ Converging air is moving horizontally, ✓ either in the upper atmosphere or at QUESTION 3 the Earth’s surface, ✓ where subsidence will result. ✓ 1. T ✓ 4. T ✓ When air converges at the Earth’s surface, it can only 2. F ✓ 5. T ✓ go one way, and that is up. ✓ The result (if the air is 3. F ✓ (5×1) moist) is cooling, condensation, and rain, ✓ usually [5] in the form of thunderstorms. ✓ Similarly, converging QUESTION 4 upper atmosphere air can only subside, ✓ causing stable Column A Column B conditions, and no rain. ✓ [10] 1. Coriolis force D. deflection caused by Earth’s rotation ✓ QUESTION 7 1. a) tropical rainforest ✓ 2. geostrophic wind E. blows parallel to isobars ✓ b) subtropical desert ✓ 3. pressure gradient G. the cause of wind ✓ 2. temperate grassland and desert and subtropical force desert ✓ 4. wind H. moving air ✓ 3. tropical rainforest and tropical seasonal forest ✓ 5. isobar F. imaginary line joining points of ✓ 4. temperate grassland and desert ✓ equal pressure 5. • tropical rainforest: Af ✓ 6. millibar C. unit of atmospheric pressure ✓ • tropical seasonal rainforest: Aw ✓ 7. upper atmosphere A. geostrophic winds occur here ✓ • savanna: Aw ✓ 8. friction B. drag between two things along • temperate grassland and desert: Cw ✓ ✓ a plane separating them • subtropical desert: Bw ✓ [10] 9. hemisphere J. half a sphere ✓ 10. equator I. divides Earth into two ✓ hemispheres [10] 6 S T U DY & M A S T E R S U P P O R T PA C K

QUESTION 8 QUESTION 10 1. rainfall variability: variation in rainfall, in 1. These are unmanned/automatic weather other words much more, or much less than stations. ✓ expected ✓✓ 2. Temperatures for the summer map are generally 2. monsoon conditions: where a large land mass can higher; summer temperatures for Upington and actually influence pressure systems to the extent Pretoria are 22 °C and 35 °C respectively. Winter that airflow is onshore in the summer (bringing in temperatures are 22 °C and 19 °C respectively. ✓✓ moisture), and offshore in the winter ✓✓ 3. a) 22 °C and 14 °C; difference = 8 °C ✓✓ 3. semi-arid: half dry, such as the Karoo, so semi- b) 34 °C and 22 °C; difference = 12 °C ✓✓ desert ✓✓ The Atlantic Ocean (cold Benguela 4. Föhn wind: hot, dry downslope wind as air current) has a moderating influence on the compresses as it moves downslope ✓✓ temperatures of Walvis Bay. Walvis Bay is 5. savanna: tropical grasslands on the fringes of the cooler than it would be if there were not the rainforest area, and lying between the equatorial cold Benguela current. ✓ regions and the deserts at 30º north and south ✓✓ 4. a) subpolar high ✓  (5×2) b) It has shifted northwards and now lies [10] nearer Namibia/Angola; this is a result of the QUESTION 9 northward shifting of the ITCZ and southern 1. high pressure – low pressure ✓ hemisphere pressure systems during the 2. arid – humid ✓ southern hemisphere’s winter. ✓✓✓ [12] 3. tropical or equatorial – polar ✓ [Total: 90 marks] 4. drought – flood ✓ 5. cause – effect ✓ (5×1) [5] S T U DY & M A S T E R T h e a t m o s p h e r e – g e o g r a p h i c a l k n ow l e d g e 7