1. Chapter 5 Climate and Terrestrial Biodiversity

2. CLIMATE: A BRIEF INTRODUCTION Weather Climate - Latitude and elevation help determine climate. Warm front Cold front High pressure Low pressure Adiabatic cooling

3. FRONTS  the movement of warm and cold masses of air creates the weather, and when the two clash, it often rains.  A warm front is defined as the transition zone where a warm air mass is replacing a cold air mass. Warm fronts generally move from southwest to northeast and the air behind a warm front is warmer and more moist than the air ahead of it. When a warm front passes through, the air becomes noticeably warmer and more humid than it was before.humid

4. FRONTS A cold front is defined as the transition zone where a cold air mass is replacing a warmer air mass. Cold fronts generally move from northwest to southeast. The air behind a cold front is noticeably colder and drier than the air ahead of it. When a cold front passes through, temperatures can drop more than 15 degrees within the first hour.

5. FRONTS

6. PRESSURE SYSTEMS The air associated with a high pressure system sinks down from above and warms as it does so and is very stable. A high pressure system (anticyclone), is a system of closed isobars surrounding a region of relatively high pressure. When compared with low pressure systems, highs tend to cover a greater area, move more slowly and have a longer life. When the high pressure system is located over land the weather will be typically dry and free of cloud.

7. PRESSURE SYSTEMS A low pressure system (cyclone) develops where relatively warm air ascends from the Earth's surface. These are systems of closed isobars surrounding a region of relatively low pressure. As the rising air cools, clouds will begin to form. The instability of the air will produce quite large vertical development of cumuliform clouds with associated rain showers (such as cumulonimbus cloud).

8. Adiabatic Cooling Adiabatic cooling deals with the cooling of parcels of air as they rise, or are forced up, through the atmosphere.

9. Adiabatic cooling

12. Earth’s Current Climate Zones Figure 5-2

13. Solar Energy and Global Air Circulation: Distributing Heat Climate is affected by: 1) Uneven heating of the earth’s surface 2) Seasonal changes in temperature and precipitation 3) Earth’s rotation 4) Unique properties of air & water Figure 5-3 Diagram

14. Coriolis Effect Deflection of air due to the rotation of the earth & friction between air & Earth – less effect near the equator (fewer hurricanes within 5 degrees) Figure 5-4 Coriolis Effect Trade Winds

15. Convection Currents Drive day-to- day weather patterns Rain- shadow Effect Figure 5-5

16. Convection Cells Distribute heat & moisture 6 Vertical currents at different latitudes : Hadley Cell – 0 – 30 - tradewinds Ferrel Cell – 30-60- westerlies Polar Cell- 60 – 90 - easterlies Figure 5-6

17. El Nino/ENSO Equatorial winds weaken along Eastern Pacific Surface water warms No upwelling Increased flooding in e. Pacific Drier western Pacific Fewer Atlantic hurricanes World Map

18. La Nina Exaggerated normal pattern Cooler water than normal along eastern Pacific Drier eastern Pacific Flooding along western Pacific More Atlantic hurricanes

19. Topography and Local Climate: Land Matters Rain Shadow effect Microclimates (forests, cities) Sea breezes Land breezes Figure 5-8

20. BIOMES: CLIMATE AND LIFE ON LAND Biomes – large terrestrial regions characterized by similar climate, soil, plants, and animals. Latitude vs. altitude Succulents Evergreens Deciduous plants Coniferous plants

21. BIOMES: CLIMATE AND LIFE ON LAND Figure 5-9

22. BIOMES: CLIMATE AND LIFE ON LAND Biome type is determined by precipitation, temperature and soil type Figure 5-10

23. BIOMES: CLIMATE AND LIFE ON LAND Parallel changes occur in vegetation type occur when we travel from the equator to the poles or from lowlands to mountaintops. Figure 5-11

24. DESERT BIOMES 30% of Earth’s land Evaporation exceeds precipitation. Little vegetation. –Found in tropical (Sahara), temperate (Mojave) and cold regions (Gobi). Succulent plants Deep vs. widespread roots Some plants secrete toxins into soil (sagebrush) Small animals

25. DESERT BIOMES Tropical, temperate and cold deserts. Figure 5-12

26. GRASSLANDS AND CHAPARRAL BIOMES Tropical grasslands (savannas) Temperate grasslands (prairies) Chaparral (Mediterranean, SoCal) Wet/dry season Many are fire-maintained (many plants contain oils)

27. GRASSLANDS AND CHAPARRAL BIOMES Most grasslands have alkaline soil Temperate grasslands are nutrient-rich Figure 5-14

28. Polar Grasslands Tundra - covered with ice and snow except during a brief summer (permafrost) Seasonal wetlands Lots of migratory animals & mosquitoes Figure 5-17

29. Chaparral Moderate climate Dense thickets of spiny shrubs Subject to periodic fires Figure 5-18

30. FOREST BIOMES Tropical rainforest Tropical deciduous forest Temperate deciduous forest Temperate rain forest Coniferous forest (boreal, taiga). Figure 5-19

31. Tropical Rain Forest Heavy rainfall High biodiversity Broadleaf evergreens Nutrient-poor soil High decomposition rate Figure 5-20

32. Temperate Deciduous Forest Most of the trees survive winter by dropping their leaves, which decay and produce a nutrient- rich soil Moderate rainfall Figure 5-22

33. Evergreen Coniferous Forests Mostly cone- bearing evergreen trees - keep their needles year-round Insulating factor - helps the trees survive long and cold winters Sheds snow Figure 5-23

34. Temperate Rain Forests Coastal areas (Calif., Oregon, Washington) - huge cone-bearing evergreen trees such as redwoods and Douglas fir Cool moist environment Figure 5-24

35. MOUNTAIN BIOMES High-elevation islands of biodiversity Snow-covered peaks - reflect solar radiation Release water to lower-elevation streams and ecosystems. Figure 5-25

36. Fig. 5-26, p. 123 Natural Capital Degradation Desert Large desert cities Soil destruction by off-road vehicles Soil salinization from irrigation Depletion of groundwater Land disturbance and pollution from mineral extraction

37. Fig. 5-27, p. 123 Oil production and off-road vehicles in arctic tundra Overgrazing by livestock Release of CO 2 to atmosphere from grassland burning Conversion to cropland Grasslands Natural Capital Degradation

38. Fig. 5-28, p. 124 Clearing for agriculture, livestock grazing, timber, and urban development Conversion of diverse forests to tree plantations Damage from off-road vehicles Natural Capital Degradation Forests Pollution of forest streams

39. Fig. 5-29, p. 124 Natural Capital Degradation Mountains Agriculture Timber extraction Mineral extraction Hydroelectric dams and reservoirs Increasing tourism Urban air pollution Increased ultraviolet radiation from ozone depletion Soil damage from off-road vehicles