1. (c) McGraw Hill Ryerson 2007 10.1 Distribution of Water Water exists everywhere on Earth, and covers 70% of its surface. 97% of this water is found in the oceans.  Another 2% is ice and snow, leaving only 1% as fresh water found in the ground, rivers, lakes and streams.  Finding fresh water to drink is a challenge in many places, as most fresh water is under the ground. See page 362

2. (c) McGraw Hill Ryerson 2007 The Water Cycle Earth is the only planet with water in all 3 states Water is continually cycling through the water cycle Heat energy from the Sun causes these changes to drive the water cycle. See page 364 Solid  Liquid = Melting Liquid  Gas = Evaporation Gas  Liquid = Condensation Liquid  Solid = Solidify/Freeze Solid  Gas = Sublimation Gas  Solid = Deposition

3. (c) McGraw Hill Ryerson 2007 The Water Cycle (continued) The water cycle occurs everywhere, not just oceans  Water evaporates when it is warmed, and then condenses in the atmosphere as clouds when it cools and falls as precipitation. The water then runs-off back to storage basins, or soaks into the ground.  A hydrologist is a scientist who studies water systems  An oceanographer studies oceans specifically See pages 404 - 405 Take the Section 10.1 Quiz

4. (c) McGraw Hill Ryerson 2007 10.2 How Ocean Water Differs from Fresh Water Ocean water’s salinity = 200X greater than fresh water  Average salinity of oceans is 35 parts per thousand  Oceans at equator (evaporation) and poles (ice) have the highest salinity (removing water increases salinity)  Ocean locations near rivers have low salinity, due to addition of fresh water See page 368 - 370 from the World Ocean Atlas 2001World Ocean Atlas

5. (c) McGraw Hill Ryerson 2007 Composition of Salt Water Salt water is composed of minerals dissolved during run-offs occurring over millions of years  Volcanic eruptions also release minerals from inside Earth  Sodium ions (Na + ) and chloride ions (Cl - ) are most common solids in ocean water  Na + ions and Cl - ions > 75% of all solids in ocean water  Mixed and joined in the ocean, NaCl is chemical name for salt See page 370

6. (c) McGraw Hill Ryerson 2007 Density of Salt Water  Density = how tightly packed the molecules are in an object  Less dense always floats on more dense  Eg. warm air rises above cool air, and oil floats on water  We float better in salt water than fresh water Salt water has slightly different properties than fresh water  Salt water freezes at –1.9 ºC See page 371 Take the Section 10.2 Quiz

7. (c) McGraw Hill Ryerson 2007 10.3 Sources of Fresh Water Precipitation becomes run-off as gravity pulls water down into the groundwater, a lake or an ocean basin. Run-off increases if:  precipitation falls on rock, as soils allow water to soak in  heavy rainfall saturates the ground so water can’t soak in  long periods of rainfall saturate the ground so water can’t soak in  water can flow quickly down a steep slope, not having time to soak in  there is no vegetation, as plants help to absorb water and hold soil with their root systems  there is human development and no soils Human development often alters run-off See page 376 - 377

8. (c) McGraw Hill Ryerson 2007 Drainage Basins Drainage basins are large areas where surface water all moves towards one main river  Run-off flows into streams and smaller rivers, which are tributaries of large rivers, forming a branching system  Large rivers are separated by very high ground called divides  The Rocky Mountains form the Continental Divide, which divides BC and Alberta See page 379

9. (c) McGraw Hill Ryerson 2007 Ground Water Ground water is water that soaks into the ground  Rock/ground with good porosity allows more water to enter  More pores (spaces in the rock/soil), the better the porosity  An aquifer is a layer of porous rock that allows ground water to flow, almost like a river below the surface. Humans get fresh water from  Reservoirs, natural or man-made  Wells, drilled into aquifers down to the water table, which is the top level of the zone of saturation.  The water table is very deep in deserts, but near the surface in swamps  The water table rises during wet seasons See page 380

10. (c) McGraw Hill Ryerson 2007 Glaciers Almost 66% of all fresh water on Earth is in glaciers  Glaciers form from layers of snow falling over many years  Glaciers melt slowly under their own weight, and slowly flow downhill  Glaciers cover about 10% of the Earth’s surface  Alpine glaciers (aka valley) found in mountains  Continental glaciers (aka ice sheets) cover huge areas of land.  Eg. Greenland and Antarctia  Glaciers flow until they  reach an ocean, where crevasses open and icebergs fall off  reach an area where warm temps allow as much melting as re-freezing, or recede if they melt faster than they can freeze See page 381 Take the Section 10.3 Quizction 10.3 Quiz

11. (c) McGraw Hill Ryerson 2007 10.4 Water’s Effect on Shaping Earth’s Surface Water is always moving due to the water cycle  Quick changes can happen due to floods, storms or tsunamis  Slower changes occur due to glaciers, run-off and rivers Water helps in weathering, erosion and deposition  Weathering is the breaking down of rock into smaller pieces  Physical weathering (aka mechanical) - rocks broken down by force, but still remain as the same kind of rocks  Chemical weathering - rocks broken down by chemicals into different types of matter  Erosion is the movement of pieces of broken rock to another location  Deposition is the dropping, and building up, of pieces of rock (eg. river deltas) See page 386 - 388

12. (c) McGraw Hill Ryerson 2007 Weathering by Water and Ice Physical weathering  Occurs most quickly where the climate includes high levels of precipitation and large temperature changes (between night and day, and also from season to season)  Ice wedging (aka frost wedging) weathers rocks due to the expansion of water as it freezes Chemical weathering  Occurs most quickly where climate is warm, there is high levels of rainfall and pollution  Water + oxygen = much chemical weathering, including rusting  aka oxidation  Plants also aid in chemical weathering  Lichens, decomposing plants See page 389

13. (c) McGraw Hill Ryerson 2007 Weathering by Water and Ice (continued) Chemical weathering also occurs underground  Water + carbon dioxide = carbonic acid, which dissolves rock  Groundwater becomes acidic, and reacts with calcium carbonate in some rocks to dissolve the rocks  Limestone has high levels of carbonate  Over time, large spaces are created underground  Sinkholes, caves and karst are formed this way See page 390

14. (c) McGraw Hill Ryerson 2007 Erosion by Water and Ice Erosion by water  Moving water breaks down rock into sediment  Sediment can be eroded far away and deposited  V-shaped valleys are carved by flowing water  Rapids create more weathering as water moves faster  Ocean waves continually erode shoreline  Gravity can cause landslides and avalanches Erosion by ice  Glaciers once covered all of BC (2 km deep, 10 000 years ago)  leave striations (scratch marks) on rocks  form U-shaped valleys  can move large rocks long distances See pages 392 - 393

15. (c) McGraw Hill Ryerson 2007 Glacial Effects See page 394 ArêteCirque Fiord (or fjord) Hanging Valley Horn Narrow ridge (high ground) between two cirques Bowl-shaped valley at the head of a glacier A narrow inlet of ocean between steep cliffs carved by glaciers U-shaped valley cut off by a bigger valley created by a larger glacier Pyramid-shaped peak located between three cirques Images from http://pubs.usgs.gov/of/2004/1216/a/a.html

16. (c) McGraw Hill Ryerson 2007 Deposition by Water and Ice See page 395 Take the Section 10.4 Quiz After erosion, sediments are eventually deposited  A delta forms where a river empties into a calm basin  Glaciers deposit many different forms of sediment ErraticEskerMoraineOutwash Large boulder deposited on the ground by a glacier Winding ridge of material deposited by a stream running under a glacier Ridge of rocky material deposited by a glacier, are found at the sides and farthest advance of a glacier. Material deposited by water from melting glaciers Images from http://pubs.usgs.gov/of/2004/1216/a/a.html