Chapter 9 The Hydrosphere

Physical GeographyA Landscape Appreciation, 9/e

Animation Edition

Victoria Alapo, InstructorGeog 1150

The Hydrosphere

The Hydrologic Cycle

The Oceans

Permanent Ice

Surface Waters

Underground Water

The Hydrologic Cycle

Earth Moisture Inventory (next slide)

Movement of WaterSurface to Air

Air to Surface

On and Beneath Surface

Earth Moisture Inventory

Oceans: 97.2% Underground water: 0.5%

Glaciers: 2.0% Surface Water: 0.25% (Rivers / streams, only: 0.0001%)

The Hydrologic Cycle

Moisture BalanceOceans Versus Continents

The OceansOceans and Seas

Seas, gulf and bays are landlocked or partially landlocked smaller bodies of water (see map & table, pg 264).See next slides for various oceans & seas.Pacific Ocean houses some of the world’s disastrous storms Pacific Ring of Fire (pg 425 & 430).

Characteristics of Ocean Waters (next slides)Movement of Ocean Waters

Tides – pg 269. Vertical movement of oceans caused by gravitational pull of the moon (know this).Currents – due to wind flow and Coriolis effect (pg 95)Waves – mostly shapes (pg 590)

Oceans and Seas

Four oceans

Characteristics of Ocean Waters

Chemical composition – 3.5% salt, by weight!Temperature – colder with depth, freezing point is 28 degrees.Density – denser with depth (more pressure)

Fig. 9-5

Permanent IceGlaciers – 2% of water storage (also see interesting info on pg 271).

Oceanic Ice Forms

Permafrost Glaciers

Oceanic Ice Forms

Earth’s Largest Ice

Pack

Extent of Permafrost

Permafrost –

Permanently frozen water in subsoil

Surface WatersLakes – opposite of islands. Some formed by glaciers, others by tectonic forces. No size limit; very small lakes are ‘ponds’. Most are freshwater. See next slide and pg 275-277.

Swamps and Marshes

Rivers and Streams – interchangeable, but a stream is smaller.

World’s Largest Lakes

Human Alteration of Natural Lakes

Fig. 9-C. Aral Sea is shrinking due to dam construction and diversion of water for irrigation of agricultural land.

Aral Sea

Fig. 9-18, pg 277

Swamps and Marshes

• Fig. 9-20.

Swamps have trees

Marshes have grasses and rushes

Major Drainage Basins

A drainage basin is all the land drained by a river and its tributaries, i.e. where all its water comes from.

Rivers and Streams

Underground WaterAquifers and Aquicludes (next slide)

Zone of SaturationWater Table – top of saturation zone (next slide)

Cone of Depression (next slides)

Zone of Confined Water – confined water btw 2 aquicludes (see Artesian Well slide)

Artesian Systems

The Ogallala Aquifer

Aquifers and Aquicludes

Aquifers are permeable rock that holds water e.g. sandstone.

Aquicludes are impermeable materials which hinder water movement e.g. clay

Cone of Depression

This is when water level drops in a well, in the shape of a ‘cone’, because water is being taken up faster than can flow in to replace it.

Artesian Well

When a well is dug and the pressure is so high that the water rises to the surface. It “pumps itself”. Pg 283.

Artesian System

The Ogallala Aquifer

Found in the Great Plains (Midwest U.S.). Allows farmers to irrigate, but it’s being endangered.