Chp. 5 - GLACIERS, Deserts, and Wind

Types of Glaciers

  1. valley/alpine - are bounded by the walls of the valley, flow in the direction of the valley
  2. ice sheets - larger scale (continental), flow in all directions, cover all but the highest peaks
  3. ice caps - smaller scale than ice sheets, but cover large upland areas and plateaus
  4. piedmont - one or more valley glaciers flow in adjacent lowlands

Glacial Movement (Figure 5.4, p. 127)

Glacial Erosion

Rate of glacial ersosion depends on:
  1. rate of glacial movement
  2. thickness of the ice
  3. shape, abundance, and hardness of the rock fragments
  4. erodibility of the underlying surface
alpine vs. ice sheet - one sharpens, one blunts features

Landforms Created by Glacial Erosion (Figure 5.7, p. 130)

Glacial Deposits

Drift - sediments of glacial origin, no matter how, where, or in what form they were deposited

Causes of "Ice Ages"

A. Surface feature changes do to Plate Tectonics
  1. location of land masses
  2. sizes of land masses
  3. oceanic circulation

B. Variations in the Earth's orbit

  1. eccentricity - shape of orbit
  2. obliquity - tilt of Earth's axis
  3. precession - wobble of axis
Proposed by Yugoslavian scientist Milutin Milankovitch

it is the differences in seasonal change, not overall amount of solar energy reaching the Earth.

Two things to take your mind off the cold weather!

other Chp. 5 readings

skip p. 141 - 145 - Deserts

read p. 145 - 147 - Wind erosion & Wind deposits - RFC , skip all sand dunes

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