Website Lecture 4 The Physical Environment Continued

Transcription

1 Website Lecture 4 The Physical Environment Continued 1

2 Lecture 4 1. Weather and Climate Global Local 2. Internal Planetary Processes Layers Plate Tectonics Earthquakes Volcanos Weather and Climate 2

3 Weather and Climate Weather and Climate Weather The conditions in the atmosphere at a given place and time Temperature, precipitation, cloudiness, etc. Day to day changes in the atmosphere 3

4 Weather and Climate Weather - short term variation in weather (weeks, months) NOT indicative of Climate Weather and Climate The average weather conditions that occur in a place over a period of years, decades, etc. Two most important factors: temperature and precipitation 4

5 Climate Zones (revise in 50yrs?) Weather and Climate 5

6 6

7 Non-El Nino Years El Nino Years 7

8 Weather and Climate Weather and Climate Intensifies during the winter 8

9 Weather and Climate Rain Shadows Mountains force humid air to rise Air cools with altitude, clouds form, and precipitation occurs (windward side) Dry air mass moves leeward side of mountain 9

10 Rain Shadows True-color satellite image of Oregon shows the rain shadow effect Tornadoes Powerful funnel of air associated with a severe thunderstorm Formation Strong updraft of spinning air forms as mass of cool dry air collides with warm humid air Spinning funnel becomes tornado when it descends from cloud 10

11 Tornadoes Wind velocity = up to 300mph Width as large as 2miles U.S. has more tornadoes than anywhere else Tropical Cyclones Giant rotating tropical storms Wind >73mph, many >155mph Many names: Hurricane (Atlantic), typhoon (Pacific), cyclone (Indian Ocean) 11

12 Tropical Cyclones Internal Planetary Processes 12

13 Internal Planetary Processes Layers of the earth Lithosphere Outermost rigid rock layer composed of plates Asthenosphere Just below the Lithosphere, comprised of hot soft rock Internal Planetary Processes Plate Tectonics- study of the processes by which the lithospheric plates move over the asthenosphere 13

14 Internal Planetary Processes Plate Boundary - where 2 plates meet Internal Planetary Processes Plate Tectonics- study of the processes by which the lithospheric plates move over the asthenosphere Plate Boundary - where 2 plates meet Divergent Two plates move apart Convergent Two plates collide Transform Plates move horizontally, opposite but in parallel 14

15 Internal Planetary Processes Divergent Plate Boundary Hydrothermal Vents 15

16 Internal Planetary Processes Convergent Plate Boundary Internal Planetary Processes Convergent Plate Boundary 16

17 Internal Planetary Processes Transform Plate Boundary Plates move horizontally, opposite but in parallel Internal Planetary Processes Transform Plate Boundary 17

18 Plates and Plate Boundaries Earthquakes Caused by the release of accumulated energy as rocks in the lithosphere suddenly shift or break Occur along faults Energy released as seismic wave 18

19 Earthquakes Richter Scale measures magnitude in two ways: Each unit 10x more shaking than the level below it. Each unit 30x more energy relased than the level below it Earthquakes - California 19

20 Earthquakes - California Earthquakes - California 20

21 Tsunami Giant undersea wave caused by an earthquake, volcanic eruption or landslide, Travel > 450mph Tsunami 21

22 Tsunami Tsunami 22

23 Tsunami Tsunami wave may be 1m deep in ocean Becomes 30m high on shore Magnitude 9.3 earthquake in Indian Ocean Triggered tsunami that killed over 230,000 people in South Asia and Africa Volcanoes Magma pushes through plate reaching surface becoming lava 23

24 Volcanoes occur at Volcanoes Subduction zones (Cascade Volcanoes) Spreading plates (Mid-Ocean Ridge) Above hot spots (Hawaiian Volcanoes) Volcanoes - Cascades 24

25 Volcanoes -Cascades Ring of Fire 25

26 Volcanoes - Hawaii Volcanoes Mid Ocean Ridge 26

27 ? 27