Chapter 6. Climate, Terrestrial Biodiversity, and Aquatic Biodiversity

1. Chapter 6. Climate, Terrestrial Biodiversity, and Aquatic Biodiversity Section 6-1 Weather and Climate: A Brief Introduction

2. What is weather? Short-term set ofphysical properties of the troposphere at a particular place and time. Temperature Pressure Humidity Precipitation Sunshine Cloud cover

3. What is weather? Meteorologists use equipment to obtain data on weather variables: Atmospheric pressure Precipitation Temperatures Wind speeds locations of air masses and fronts This data is fed into computer models to draw weather maps to forecast the weather

4. What is Climate? Climate is a region’s general pattern of atmospheric of weather conditions over a LONG period of time Average temperature and average precipitation are the two main factors that determine a region’s climate

5. Climate is Climate and its effects the average weather patterns for an area over a long period of time (30 - 1,000,000 years). It is determined by and Average Temperature Average Precipitation which are influenced by latitude altitude ocean currents and affects what they grow and eat where people live how people live

6. 5 factors that determine global air circulation patterns Uneven heating of Earth Seasons Earth’s rotation Variation of sun’s output Properties of air and water

7. 1. Uneven Heating of the Earth

8. Cold Cool Temperate Warm Temperate Tropical (equator) Tropical Warm Temperate Cool Temperate Cold Climate type

9. 2. Seasons

10. 3. Rotation of Earth

11. 4. Variations in solar output

12. 5. Properties of air and water Convection Cells – circulate air, heat, and moisture both vertically and from place to place. 5. Properties of air and water

13. How do ocean currents affect regional climates? The five factors PLUS differences in water density create warm and cold ocean currents. These currents (driven by winds and earth’s rotation) redistribute heat and therefore influence climate and vegetation If ocean’s currents suddenly stopped flowing, there would be deserts in the tropics and thick ice over northern Europe, Siberia, and Canada Currents also mix ocean waters and distribute nutrients and dissolved oxygen needed by aquatic organisms

14. 60,000 Nikes spilled into the Pacific

15. Warm ocean current Warm temperate Highland Polar (ice) Cold ocean current Dry Major upwelling zones Subarctic (snow) River Tropical Cool temperate CD ani 2

16. Solar radiation Convection cell Equator Warm current Cool current Warm air Cool current Warm water Warm current Polar front Cool air Ocean Currents Cold water Surface Currents Midlevel currents Bottom Currents

17. Movement of surface water Wind Diving birds Fish Upwelling Zooplankton Phytoplankton Nutrients Upwellings – winds push surface water away from the land, this water is replaced by cold-nutrient rich bottom water – brings deep cool water to the surface

18. Cold, dry air falls Cell 3 North Relationship between global air circulation and biomes Moist air rises — rain Polar cap Cell 2 North Arctic tundra Evergreen coniferous forest 60° Cool, dry air falls Temperate deciduous forest and grassland Desert 30° Cell 1 North Moist air rises, cools, and releases moisture as rain Tropical deciduous forest Tropical rain forest 0° Equator Tropical deciduous forest Cell 1 South 30° Desert Temperate deciduous forest and grassland Cool, dry air falls 60° Cell 2 South Polar cap Moist air rises — rain Cold, dry air falls Cell 3 South

19. El Nino - “The Christ Child” El Niño is a disruption of the ocean-atmosphere system in the Tropical Pacific having important consequences for weather and climate around the globe.

20. What is the El Nino-Southern Oscillation (ENSO)? Occurs in the Pacific Ocean Prevailing westerly winds weaken or cease Surface water along the South and North America coasts become warmer The normal upwelling of cold, nutrient rich water are suppressed Bad fishing

21. Surface winds blow westward EQUATOR SOUTH AMERICA Warm waters pushed westward AUSTRALIA Warm water Thermocline Cold water Normal Conditions

22. Winds weaken, causing updrafts and storms Drought in Australia and Southeast Asia EQUATOR Warm water flow stopped or reversed SOUTH AMERICA AUSTRALIA Warm water deepens off South America Warm water Thermocline Cold water El Niño Conditions

23. El Niño Drought Unusually high rainfall Unusually warm periods

24. La Nina Cooling counterpart of El Nino Means more Atlantic hurricanes, colder winters in Canada and northeastern US, warmer and drier winters in the southeastern and southwestern US and more wildfires in Florida

25. How does the chemical make-up of the atmosphere lead to the greenhouse effect?

26. The Greenhouse Effect • Water vapor H2O • Carbon dioxide CO2 • Methane CH4 • Nitrous oxide N2O • Chlorofluorocarbons CFCs Major Greenhouse Gases

27. Are Greenhouse Gases GOOD or BAD? THEY’RE BOTH GOOD - without greenhouse gases, the Earth would be too cold for life BAD - too many greenhouse gases may lead to global warming

28. Where do greenhouse gases come from? ALL OF US!!! Burning fossil fuels releases: CO2 H2O N2O Cows release methane (CH4) Various refrigerants use CFCs

29. How does the chemical make-up of the atmosphere create the ozone layer? Is this what the hole in the ozone layer looks like?

30. Did Mrs. Gallo destroy the OZONE… it’s possible…

31. Ozone In a nutshell – we will discuss in detail later in the year In stratosphere oxygen (O2) is converted to ozone (O3) and back to oxygen by a sequence of reactions initiated by UV radiation from the sun Results in a thin veil protecting us from 95% of sun’s harmful UV radiation Evidence indicates that chemicals added to atmosphere by our activities are decreasing the level of protection Thermal cap – warm layer of air created by ozone layer that prevent churning gases in the troposphere from entering the stratosphere, important in determining average temp of troposphere and climate

32. Microclimates – local climatic conditions that differ from the general climate of a region a Winds carry moisture inland from Pacific Ocean b Clouds, rain on windward side of mountain range c Rain shadow on leeward side of mountain range Dry habitats Moist habitats Rain Shadow Effect - lower precipitation and semiarid or arid conditions on the leeward side of a mountain-

33. Rain Shadow Effect

34. Warm air ascends Cool air descends Land warmer than sea; breeze flows onshore Sea Breeze

35. Cool air descends Warm air ascends Land cooler than sea; breeze flows offshore Land Breeze

36. Weather Extremes Tornadoes Tropical cyclones Atlantic Ocean = hurricanes Pacific Ocean = typhoons

37. Descending cool air Severe thunderstorms can trigger a number of smaller tornadoes Severe thunderstorm Rising warm air Tornado forms when cool downdraft and warm updraft of air meet and interact Rising updraft of air

38. Tropical Cyclones Rising winds exit from the storm at high altitudes. The calm central eye usually is about 24 kilometers (15 miles) wide. Gales circle the eye at speeds of up to 320 kilometers (200 miles) per hour. Moist surface winds spiral in towards the center of the storm

39. Hurricane Sandy - FRANKENSTORM Hurricane Sandy was the largest Atlantic hurricane on record The second-costliest Atlantic hurricane in history, only surpassed by Hurricane Katrina in 2005 Hurricane - A hurricane is a tropical storm with winds that have reached a constant speed of 74 miles per hour or more. The eye of a storm is usually 20-30 miles wide and may extend over 400 miles. The dangers of a storm include torrential rains, high winds and storm surges. A hurricane can last for 2 weeks or more over open water and can run a path across the entire length of the Eastern Seaboard Video – Weather Channel

40. Prince William Sound Gulf of Alaska Risk of Tornadoes CANADA Highest High Medium UNITED STATES Low Grand Banks Tropical Cyclone Frequency High Moderately high Atlantic Ocean MEXICO