2013 DYNAMIC PLANETEVENT PREPARATION COURSE

COURSE INSTRUCTOR:

Mark A. Van Hecke2013 Dynamic PlanetNational Event SupervisorCTT+ Certified Trainer

East China, Michiganmvanhecke@comcast.net

Coach

Students

Event Rules

SCIENCE OLYMPIAD EVENT TRAINING

ABSORB

DO

CONNECT

APPLICATION OF HORTON’S ONLINE LEARNING PARADIGM TO SCIENCE OLYMPIAD

EVENT TRAINING

A big part of success in Science Olympiad Earth-Space Science Events is the acquisition of a rich and diverse body of knowledge related to each of the events.

CONTENT KNOWLEDGE

This is the ‘absorb’ of the Lesson.

Excursions are ‘side trips’ that we take when we are on vacation….the same goes for new experiences that we can learn about in our education.

EXCURSIONS

Whenever you see this icon in the bottom right of your screen, just Click it to go to the Excursion

EXCURSIONS

Excursions are the ‘Do’ component of the Lesson.

‘Hot Links’ refer to interesting websites that relate to what you are learning.

If you see the icon shown below in the bottom right of each slide, click it to access an interesting website that will help you to see or better understand what you are learning.

HOT LINKS

You will also need to download the following textbook. Click the URL below to download it (PDF) at no cost.

http://gsscienceolympiad.wiki.elanco.net/file/view/Glaciers-Smith.pdf

TEXTBOOK

When you see it on the bottom right side of a slide, Click this Icon to see which pages you will need to read and what you should learn from the assignment.

Certain Excursions and activities in a Lesson may require additional supplies.

OTHER THINGS YOU WILL NEED

From time to time, we’ll pause the lesson to reflect on what we should have learned up to that point.

SUMMARIES

At the end of the lesson, there will be several sample tournament questions to answer and/or problems to solve. This is the ‘connect’ of the lesson.

SAMPLE EVENT QUESTIONS

LESSON ONE: WHAT ARE GLACIERS?

1. How glaciers are formed

2. How to describe the structure of a glacier and identify a glacier’s zone of accumulation and zone of ablation.

What You’ll Learn in This Lesson:

3. How to determine the zones of accumulation and ablation of a glacier.

4. Explainthe ‘movement’ of glaciers and determine the direction of glacial flow.

WHAT ARE GLACIERS?And why is it important to study them.

A glacier is a perennial mass of ice that originates on land, and has movement.

Glaciers store 75% of the Earth’s fresh water and cover about 15 million square kilometers-about 10% of our planet’s surface.

If all of this ice melted, sea levels would rise about 70 meters worldwide.

You could say that today’s glaciers are remnants from the last ‘Ice Age’, when ice covered 32% of the land and 30% of the oceans.

From time to time, the climate of the Earth changes allowing cooler temperatures to endure for longer periods throughout the year.

This allows glacial ice to expand into mid-latitude regions such as the Midwestern United States, New England and Northern Europe.

These periods of expanding glacial ice are known as Ice Ages.

Scientists know that over the past 750,000 years, there have been eight glacial ice age cycles.

These Ice ages were separated by warmer periods known as interglacial periods.

We are currently living in what is believed to be the end of an interglacial period.

Glaciers also influence the direction of atmospheric and oceanic currents that regulate global temperature.

Could the melting of glacial ice alter ocean and atmospheric currents creating a colder Earth?

Or will ever-increasing levels of CO2 turn Earth into another Venus where daily temperatures exceed 800°F on most days?

Glaciers also sculpt and shape the land leaving erosional and depositional landforms.

Here in Michigan, the Great lakes were created by glaciers during the last Ice Age some 10,000 years ago.

Glaciers also created thousands of kettle lakes throughout Michigan and other Midwestern states

SUMMARY

• Glaciers are large masses of ice originating on land that form over an extended period of time.

• Gradual changes in Earth’s orbit over many thousands of years result in long periods of glacial ice covering the Northern Hemisphere followed by periods of warmth and glacial retreat (interglacial).

• Glaciers form many erosional and depositional landforms on the surface of the Earth.

• Glaciers also influence Earth’s atmospheric and oceanic currents.

HOW ARE GLACIERS FORMED?

A glacier will form in a given location if the amount of snowfall (accumulation) exceeds the rate of melting (ablation).

In glacial formation, this is termed as the zone of accumulation.

A glacier’s zone of accumulation is usually located at its highest elevation.

As snow accumulates over time in a given location, each new layer of snow pushes down on the layers of older snow beneath it.

As a result of this compression, older layers of snow are melted, crystallized and compacted together.

Snowflakes are changed to firn- an intermediate stage between snow and ice.

Individual ice crystals near the melting point become semiliquid and slick allowing them to glide over other crystal planes.

As this ice is pushed further and further down by more accumulating snow, the crystals interlock and begin to look and behave more like rock.

A glacier’s zone of melting (ablation) is usually located at its lowest elevation.

This is termed a glacier’s zone of ablation.

Formation of Glaciers

There are three criterion for a mass of ice to be a glacier:

• They are made of ice • They form on land• They have movement

Glaciers are made of air, ice crystals, water and rock debris.

Each of these components will be addressed in our study of glaciers. For now, let’s look at ice crystals-the building blocks of glaciers.

Ice Crystals

Ice crystals are weak and can be made to slip on planes parallel to the basal plane as shown.

As you will see this feature of ice crystals helps to explain their flow or ‘movement.’

Density Of Water

One of water’s most unusual characteristics is its density.

Unlike many substances, water in its solid state (ice) is less dense than it is in its liquid state.

This means that liquid water may exist beneath some glaciers and that glaciers may even float

GLACIERS FORM ON LAND

All glaciers form on land. Glaciers may extend into bodies of water such as lakes and oceans, but they do not originate in the water.

MOVEMENT

Glaciers must have flow or movement.

SUMMARY

• Glaciers form when the amount of snowfall exceeds the rate of melting

• In the process of glaciation, snow is changed into a compacted form known as firn. Firn is then further compacted into a dense glacial ice.

• Water in a solid state is less dense than water in a liquid state. This allows ice to float on top of water.

• The zone of accumulation is where glacial snow accumulates. The area where glacial melting exceeds the rate of accumulation is known as the zone of ablation.

THE MOVEMENT OF GLACIAL ICE

Glaciers move by the processes of internal deformation and basal sliding. Let’s take a look at how each of these processes work.

Each snowflake is a hexagonal molecule with each oxygen atom bonded to a hydrogen atom in a ring as shown

Glacial movement occurs when an accumulating mass of ice becomes too heavy to maintain its shape.

The mass of glacial ice begins to move in a downslope direction over the top of this liquid, plasticized ice

Rotation of grains

Melting and freezing

Internal slipping

Glacial calving occurs as glaciers move off to the sea and large chunks of ice break off from the main body of the glacier.

Icebergs are chunks of calved ice that have broken off of the main body of the glacier and float in the ocean.

SUMMARY

• The increased mass of a glacier at its zone of accumulation causes individual ice crystals near the bottom layer of the glacier to partially melt and become plastic allowing individual crystals to slide over one another across their basal planes

• Glaciers that reach a shoreline may ‘calve’ or break away from the main body of the glacier. If they drift into the sea they are known as Icebergs.

SAMPLE EVENT QUESTIONS

Diagram a GlacierIdentify Zones of Accumulation and Ablation

EXCURSION 1

Identify each of the layers shown in the process of glacial formation.

EXCURSION 1

Move your mouse over the image shown of Malaspina Glacier until you locate the zone of accumulation.

Then do the same to locate the zone of ablation.

The Density of Water

EXCURSION 2

Check out this excellent activity provided by New York University. In it you will attempt to explain why ice floats on top of water and do experiments to determine why. http://www.nyu.edu/pages/mathmol/modules/water/density_exp.html

Determining the Direction of Glacial Ice Flow

EXCURSION 3

USGS topographic maps will often be used to identify different glacial features.

Look at the map on the next slide and answer the question shown below it.

What direction did the glaciers flow? How can you tell? Back to Previous

TEXTBOOK 1

Read pages 6-22 of Glaciers, Climate and Landscape

Back to Previous

TEXTBOOK 2

According to Smith, how does glacial ice meet the criteria of being a mineral?

Back to Previous

TEXTBOOK 3

Describe the ‘movement’ of glacial ice (pages 20-22).

Back to Previous