Topic: In what conditions are glaciers and ice sheets created?

Target group:

First‑grade student of high school or technical school, basic programme

Core curriculum

(geography, high school / technical school)

General requirements

II. Skills and application of knowledge in practice.

3. Identifying relations between particular elements of the geographical environment (natural, socio‑economic and cultural).

Specific requirements

IV. Hydrosphere: water resources on the Earth, seas, sea currents, river network, glaciers.

Student:

5) explains the process of formation of glaciers and presents their occurrence on Earth.

General aim of education

To acquaint students with the processes leading to the formation of glaciers and ice sheets.

Key competences

  • communication in foreign languages;

  • digital competence;

  • learning to learn.

Criteria for success
The student will learn:

  • describe the conditions in which glaciers and ice sheets are formed;

  • explain how glaciers shape the bedrock;

  • list the reasons for the current distribution of glaciers on Earth;

  • present the consequences of glaciations.

Methods/techniques

  • activating

    • discussion.

  • expository

    • talk.

  • programmed

    • with computer;

    • with e‑textbook.

  • practical

    • exercices concerned.

Forms of work

  • individual activity;

  • activity in pairs;

  • activity in groups;

  • collective activity.

Teaching aids

  • e‑textbook;

  • interactive whiteboard, tablets/computers.

Lesson plan overview

Introduction

  • The teacher asks students to read the entire material from the lesson „Under what conditions glaciers and ice sheets are created, and then appoint people who will discuss the following issues: the boundary of eternal snow and its course for different latitudes; formation of glaciers and ice sheets; examples of traces of glaciers in Polish mountains.

Realization

  • While students give examples of glaciers and ice sheets, one person records them on the board along with their latitude and altitude. The class tries to locate the given examples in a graph showing the course of the border of eternal snow depending on the geographical latitude. If necessary, the teacher gives instructions.

  • The pupils reflect together on the contemporary course of the border of eternal snow, trying to connect it with such factors as the climate (average temperature, amount of rainfall) and terrain. A volunteer or a person indicated by the teacher formulates conclusions resulting from the discussion.

  • Students carry out the interactive exercises checking the level of knowledge learned during the lesson. The teacher initiates a discussion during which the correct solutions for all the exercises performed by the students are discussed.

  • Work of the whole class team. Students stand in a circle. The teacher encourages them to play: throws a ball or mascot to one of the students, saying the English word or notion learned in the lesson. The student gives the Polish equivalent, mentions another word in English and throws a ball or mascot to a friend or colleague.

Summary

  • The teacher briefly presents the most important issues discussed in class. He answers the additional questions of the proteges and explains all their doubts. Students complete notes.

Homework

  • Make at home a note from the lesson using the sketchnoting method.

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The following terms and recordings will be used during this lesson

Terms

firn
firn
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Nagranie dźwiękowe słówka

lód ziarnisty - forma przejściowa między śniegiem a lodem, powstająca na skutek częściowego topienia i ponownego zamarzania śniegu oraz ciśnienia, jakie wywierają jego nadległe warstwy

snow line
snow line
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Nagranie dźwiękowe słówka

linia śniegu - umowna linia, powyżej której w ciągu roku więcej śniegu przybywa, niż topnieje

ice sheet
ice sheet
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Nagranie dźwiękowe słówka

pokrywa lodowa - rozległa pokrywa lodowa zajmująca znaczną cześć lądu, a nawet cały kontynent

firn field
firn field
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Nagranie dźwiękowe słówka

obszar lodowca - część lodowca znajdująca się powyżej granicy wiecznego śniegu, gdzie więcej śniegu przybywa, niż topnieje

Texts and recordings

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Nagranie dźwiękowe abstraktu

In what conditions are glaciers and ice sheets created?

Glaciers and ice sheets are created in places where the average annual air temperature is below 0°C, where there are snowfalls, and, simultaneously, where the terrain is almost flat or even concave. The conventional line, above which snowfall during the year is higher than the loss of snow due to melting and evaporation, i.e., where there are conditions conducive to the creation of glaciers, is called the snow line.

In areas located above this line, the snow cover lies in the summer and is fed by new snowfalls in winter. Year after year, the snow cover gets thicker and thicker. Under the influence of gravity, a layer of snow is pressed and gradually turns into granular ice also known as firn, and, ultimately, into glacial ice. The area where this process occurs is called a firn field. Most often, firn fields form in upper parts of valleys or at the bases of mountain peaks. When a lot of ice has been created, it becomes partially malleable under the pressure of the higher layers, and starts to flow below the snow line in the form of glacier tongues. A firn field and the tongue that flows out of it are called a mountain glacier.

In suitable climatic conditions (low temperature, more snowfall during the year than loss of snow due to melting and evaporation) and in areas with favorable terrain (concave or flat), many glaciers may come together in a huge massif called an ice sheet. Ice sheets can cover almost the whole continent, or a large part of it. In Pleistocene (2.6 million – 11.7 thousand years ago), vast areas of the northern hemisphere were repeatedly covered by ice sheets.

Currently, in polar areas, the snow line runs at a height of about 200–1000 m above sea level. It reaches the sea level only in Greenland and Antarctica. In the temperate zone, it occurs at a height of about 800–3200 m above sea level. In the tropical zone and in the Himalayas, it runs at 5000–6000 m above sea level, and on the equator it goes down to about 4500–5000 m above sea level.

  • The line above which there are conditions conducive to the creation of glaciers is called the snow line.

  • In suitable climatic conditions and in areas with favorable terrain, many glaciers may come together in a huge massif called an ice sheet.

  • Considerable areas of the Earth have many times been glaciated.