MAR 110 Lecture #2 A: Energy Sources B: Earth InteriorMAR 110: Lecture 2 Outline – Energy / Earth...

MAR 110: Lecture 2 Outline – Energy / Earth Interior

1

MAR 110 Lecture #2

A: Energy Sources

B: Earth Interior

How can energy do work? Energy is required to move something

with force – that do work . For example, the energy of the moving water causes the wheel to turn. (UWaC)


2


3

What is potential energy? These are examples of various forms of potential or “stored’ energy. Water behind a dam can be used to generate electricity; wood can be burned to produce heat; food is converted into energy for body movement. (UWaC)


4


5


6

Internal Energy Source-Radioactive Decay Radioactive decay deep inside the earth produces geothermal energy (heat) as well as create convection currents within the mantle that drive plate tectonics. (?)


7

External Energy Source-the Sun The sun is the source of nearly all the energy used on earth, mostly in the form of heat which drives both oceanic and atmospheric processes. (UWaC)

Solar Energy and the Hydrologic Cycle Partition of solar energy showing the relative amounts reflected, absorbed and radiated energy in the earth-ocean-atmosphere system. (?)


8

Hurricane Structure Warm moist air enters at the bottom of a hurricane and spirals upward through convection. As the air moves upward it cools and releases moisture, strengthening the storm. (?)


9

The Earth’s Interior: Basis for Plate Tectonics

Tsunami “Triggers” Four processes that can trigger a tsunami. Clockwise from upper left: volcanic explosion, underwater faulting, meteor impact, landslide. In order for a tsunami to be generated a large volume of water must be displaced. (NG)


10

Interior Earth Structure (left) The Earth’s interior is composed of multiple spherical layers: inner core, outer core, mantle, and a relatively thin crust. (right) The properties of the mantle vary from the brittle lithosphere (part of which is the earth’s crust) to the relatively fluid asthenosphere to the more rigid mesosphere. The denser layers are deeper. (ItO)

Density

The density of a material is the amount of that

material contained in a “unit volume” such as a cubic centimeter (or cubic meter). In short , mass per unit volume or mass DENSITY = -----------

volume The material’s density can change because the amount of material within a fixed (or unit) volume can depend on its temperature. This is because temperature T change cause the material to expand or contract..


11

Earth Crustal Configuration The relatively thin oceanic crustal layer and the thicker continental crustal layers “float” on the mantle below…they are said to be isostatic equilibrium. It is their layer thickness differences that cause the continental crust to rise higher out of the mantle relative to the thinner oceanic crust. The different densities of the rock material only make slight differences. The resulting ocean basin depression catches the water that runs off of the land. Note the ~ 20 times (20x) vertical exaggeration of this profile. (ItO)


12

Hydrostatic Equilibrium Any object placed in a fluid displaces a volume of fluid equal in mass to that of the object. When the density of the fluid is greater than that of the object, the volume displaced is less than the volume of the object, causing the difference to float above the surface of the fluid. (ItO)

Floating Icebergs

– An Example The density of the two icebergs is approximately equal, the percentage of the icebergs above the water is also equal. With the one on the left having a larger mass, more water is displaced but also more of the iceberg lies out of the water. (ItO)

MAR 110 Lecture #2 A: Energy Sources B: Earth InteriorMAR 110: Lecture 2 Outline – Energy / Earth...

Documents

Transcript of MAR 110 Lecture #2 A: Energy Sources B: Earth InteriorMAR 110: Lecture 2 Outline – Energy / Earth...