3 Forms of Energy Transfer

1. 3 Forms of Energy Transfer • 1. conduction • transfer of energy (mostly in solids) by collisions of particles • 2. convection • transfer of energy by currents moving through liquids or gases (caused by density differences) • 3. radiation • transfer of energy through empty space (no molecules needed) • Ex. energy from the Sun

2. Recycling of Materials Amongst Earth’s Spheres • Earth is constantly recycling materials • maintains an overall balance through biogeochemical cycles • water • carbon • etc.

3. Solar Energy Drives the Water Cycle condensation

4. The Water Cycle 1. precipitation • water that falls from clouds to Earth • drizzle, rain, snow, sleet, hail

5. 2. infiltration • water soaks into soil from the surface • 3. ground water • water under the ground; soil is saturated

6. 4. evaporation • warmth from Sun causes liquid water to turn into water vapor evaporation • 5. transpiration • when plants give off water vapor through stomata in their leaves

7. 6. condensation • water vapor cools until it turns back into liquid • forming clouds, fog, or dew condensation

8. Groundwater Pollution • pollutants in soil carried by infiltration into groundwater • oil • nitrates & phosphates • from fertilizers • pesticides • farm wastes • sewage • salt • to melt ice • chemicals & hazardous wastes • and more… • can be a reason for site to be designated a “brownfield” • remediation (clean up )  expensive • prevention  best

9. Carbon Cycle

10. Changes in CO2 & Climate • CO2levels have risen steadily since mid-1800s • primarily due to human activities • combustionof fossil fuels • coal • gasoline • natural gas • deforestation • decreased photosynthesis

11. Changes in CO2 & Climate • avg. global temps have  ~1°C since late 1800s • Possible effects: • sea-level rise • more/stronger storms/hurricanes • more frequent heat waves/droughts • relocation of major crop-growing areas

12. Common Air Pollutants • air pollutant • any airborne gas or particle concentrated enough to harm people or the environment • natural causes • volcanoes • forest fires • human causes • combustion of fossil fuels (automobiles, factories, etc.)

13. Acid Rain • pollutants (SOX& NOX) react w/ H2O vapor in air • acidity measured using pH • effects • harm to plants/animals • damage to structures made of limestone/marble • remember… carbonates bubble in acid

14. Weathering • breakdown of rocks at Earth’s surface • 2 types: • chemical • mechanical(physical)

15. Chemical Weathering • rock is broken down by chemical action • changed into new substances • agents include acids & oxygen

16. Chemical Weathering • rainwater  naturally acidic • CO2dissolved in rainwater  carbonic acid • can weather carbonate-based rocks • ex. marble & limestone (CaCO3)

17. other rocks are very resistant to acid and do not weather easily • quartz-based rocks • ex. quartzite & sandstone (SiO2)

18. Mechanical (Physical) Weathering • rock is split, cracked, or broken into smaller pieces of the same material • NOT changed into new substances

19. Rock Cycle Movie The Rock Cycle • continuous process causing rocks to change from one form to another

20. BrainPop 3 Types of Rocks 3 Major Classes of Rocks • sedimentary • formed by compaction & cementing of layers of sediments • metamorphic • formed by effects of heat & pressure on other rocks • igneous • formed by solidification of hot, molten rock

21. made of sediments cover most of Earth’s surface Sedimentary Rocks

22. Metamorphic Rocks • metamorphism • process by which a rock’s structure is changed by pressure & heat

23. Examples of Metamorphic Rocks & What They Formed From • granite  gneiss • shale  slate  phyllite  schist • limestone  marble • sandstone  quartzite

24. Igneous Rocks • form due to MELTING & solidification • Intrusive • magma cools slowly deep insideEarth • crystals  medium to coarse texture • Extrusive • lava cools quickly on/above surface of Earth • crystals very small or not seen at all

25. Convection Currents in Magma • drives plate tectonics Convection in the Mantle Animation

26. What Is Plate Tectonics? • theory that describes formation, movements, & interactions of Earth’s lithospheric plates

27. Types of Plate Boundaries • Earth’s lithosphere is broken in to large plates • movement @ plate boundaries determines type • divergent • convergent • transform

28. plates move apart most are along ocean floor spreading @ mid-ocean ridges  molten rock forces through cracks (rifts) in valley Divergent Boundaries

29. Mid-Atlantic Ridge Mid-Ocean Ridge

30. Convergent Boundaries • plates move closer together

31. Transform Boundary--San Andreas Fault Animation Transform Plate Boundary • plates slide past each other at fault • stress released  earthquake • Ex. California—San Andreas Fault N

32. Ring of Fire Locations of Earthquakes & Volcanoes • occur in concentrated areas @ plate boundaries • strain builds up  earthquakes • molten rock rises  volcanic activity • Pacific Ocean  Ring of Fire Plates & Volcanoes Video