Sol, Wind, Water and Land

1. Sol, Wind, Water and Land • The sun (Sol) makes life on Earth possible • Without the sun, the temperature on Earth would be near 0 Kelvin

2. Sol • Powers all the nutrient cycles • Determinant of climate • Fusion reaction emits energy as Electromagnetic (EM) radiation • Only a nano of the sun’s energy strikes Earth and only 69 % of that is not reflected • Much is still wasted as IR into space

3. Sol • 31 % of sun’s energy striking Earth is reflected back by clouds and ground • 3% is absorbed by the clouds • 17 % absorbed by the atmospheric molecules and dust • 49 % is absorbed by the ground and oceans

4. Weather and Climate • Weather is the wind, cloud cover, temperature, pressure, temperature, precipitation and humidity of an area • Climate is a region’s general pattern of weather

5. Weather and Climate • Average temperature, precipitation, latitude and elevation determine a region’s climate • Global air and ocean currents play a significant role

6. Temperature • Changes with latitude • Sun’s energy does not reach the all areas of the Earth uniformly • Caused by Earth’s tilt and rough spherical shape • Energy hits vertically at equator – most concentrated there

7. Global Air Currents • Uneven heating by the sun • Season changes in precipitation and temperature • Rotation of the Earth • Physical properties of air, water and land

8. Currents • Tropical Zones - Trade Winds • Temperate Zones - Westerlies • Polar Zones - Polar Easterlies

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

10. Methods of Heat Transfer • Radiation • Convection • Conduction

11. Convection Currents • Global air circulation is affected by the properties of air water, and land. Figure 5-5

12. Convection Cells • Heat and moisture are distributed over the earth’s surface by vertical currents, which form six giant convection cells at different latitudes. Figure 5-6

13. Ocean Currents • Oceans absorb heat from the sun and air currents: particularly along the equator in the tropic zones • Differences in water density, salinity and temperature coupled with physical oceanography flow roughly clockwise

14. Ocean Currents • Ocean currents like wind currents can distribute energy, nutrients and species

15. Ocean Currents: Distributing Heat and Nutrients • Ocean currents influence climate by distributing heat from place to place and mixing and distributing nutrients. Figure 5-7

16. Ocean Currents: Distributing Heat and Nutrients • Global warming: • Considerable scientific evidence and climate models indicate that large inputs of greenhouse gases from anthropogenic activities into the troposphere can enhance the natural greenhouse effect and change the earth’s climate in your lifetime.

17. Topography’s Effect on Climate • Elevation • Air Currents • Precipitation

18. Topography and Local Climate:Land Matters • Interactions between land and oceans and disruptions of airflows by mountains and cities affect local climates. Figure 5-8

19. BIOMES: CLIMATE AND LIFE ON LAND • Different climates lead to different communities of organisms, especially vegetation. • Biomes – large terrestrial regions characterized by similar climate, soil, plants, and animals. • Each biome contains many ecosystems whose communities have adapted to differences in climate, soil, and other environmental factors.

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

21. Climate and Major Biomes

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 • Deserts are areas where evaporation exceeds precipitation. • Deserts have little precipitation and little vegetation. • Found in tropical, temperate and polar regions. • Desert plants have adaptations that help them stay cool and get enough water.

25. DESERT BIOMES • Variations in annual temperature (red) and precipitation (blue) in tropical, temperate and cold deserts. Figure 5-12

26. DESERT BIOMES • The flora and fauna in desert ecosystems adapt to their environment through their behavior and physiology. Figure 5-13

27. Human Impact on Deserts Due to their fragile nature, desert soils can take from decades to hundreds of years to recover from human disturbance Destruction from grazing livestock, off-road vehicles, erosion due to urban development is ongoing.

28. GRASSLANDS AND CHAPARRAL BIOMES • Grasslands (prairies) occur in areas too moist for desert and too dry for forests. • Savannas are tropical grasslands with scattered tree and herds of hoofed animals.

29. GRASSLANDS AND CHAPARRAL BIOMES • Variations in annual temperature (red) and precipitation (blue). Figure 5-14

30. Tropical grassland (savanna) Freezing point Mean monthly temperature (C) Mean monthly precipitation (mm) Month Fig. 5-14a, p. 112

31. Temperate grassland Freezing point Mean monthly temperature (C) Mean monthly precipitation (mm) Month Fig. 5-14b, p. 112

32. Polar grassland (arctic tundra) Freezing point Mean monthly temperature (C) Mean monthly precipitation (mm) Month Fig. 5-14c, p. 112

33. Temperate Grasslands • The cold winters and hot dry summers have deep and fertile soil that make them ideal for growing crops and grazing cattle. Figure 5-15

34. Temperate Grasslands • Temperate tall-grass prairie ecosystem in North America. Figure 5-16

35. Human Impact on the Prairies • Habitat destruction due to • Tilling for crops • Grazing for livestock • Towns and Cities

36. Polar Grasslands • Polar grasslands are covered with ice and snow except during a brief summer. Figure 5-17

37. Human Impact on the Tundra Short growing season means slow recovery from disturbance Tundra continues to be disturbed by oil exploration, military presence, oil pipelines and mines.

38. Chaparral • Chaparral has a moderate climate but its dense thickets of spiny shrubs are subject to periodic fires. Figure 5-18

39. Human Impact on Chaparral Human insistence on building homes on hill sides has caused increased erosion and mudslides as well as increased severe wildfires due to over suppression.

40. FOREST BIOMES • Variations in annual temperature (red) and precipitation (blue) in tropical, temperate, and polar forests. Figure 5-19

41. Tropical rain forest Freezing point Mean monthly temperature (C) Mean monthly precipitation (mm) Month Fig. 5-19a, p. 116

42. Tropical Rain Forest • Tropical rain forests have heavy rainfall and a rich diversity of species. • Found near the equator. • Have year-round uniformity warm temperatures and high humidity. Figure 5-20

43. Human Impact on Tropical Rain Forests Cleared or slash and burn for crops and timber Mining operations Rains are causing the few nutrients in the soil to leach and wash out thus leaving the land pretty much barren.

44. Human Impact on Temperate Deciduous Forests Industrialization, urbanization, timber harvest and clearing for farming has destroyed this biome. This biome has been disturbed by humans more than any other.

45. Human Impact on Coniferous Forests Old Growth coniferous forests have been cleared and replanted with fast growing pine to satisfy the pulp and timber industry. Boreal forests are being cleared to extract oil-sand leaving a barren “moon scape”

47. Human Impact on Mountain Biomes Global warming is affecting glaciers, accelerating melting Mining (mountain top removal) Urban air pollution has reached the Grand Canyon and Smokey Mountains Erosion problems from off road vehicles

48. Human Impact on Mountain Biomes Damming of surface waters Timber extraction leading to erosion. Road and power line construction. Tourist resorts

49. High A D C Temperature B E Low High Identify Biomes A to E Based on Temperature and Precipitation Levels: Answers Next Slide Precipitation

50. Answers to Previous Slide • A has high temperature and low moisture = hot desert • B has low temperature and low moisture = cold desert (tundra with permafrost) • C has medium temperatures and moisture = grassland • D has high temperature and moisture = rain forest • E has low temperature and high precipitation = arctic poles