IGEO 2

Periglaciation + Coast

100

Why can you see patterned ground in areas with permafrost?

Due to frost-heave: The thermal conductivity of a stone is greater than that of the soil. Ice crystals under the stones. Movement upwards. Or due to ground contraction: Crack - Water - Ice - Crack - Water - Ice

200

The energy acquired by waves depends on three things. Which?

The wind velocity The period of time the wind has blown The lenght of the fetch

300

Ved overskridelse af hvilket forhold mellem bølgehøjde og bølgelængde vil en bølge bryde?

1:7

400

Mention 5 out of the 6 processes of coastal erosion

Subaerial Wave pounding Hydraulic pressure Abrasion = Sand, shingle and boulders hurled against the cliffs Attrition = Rock and boulders brokken into smaller, more rounded particles Solution

500

Mention the two/three special processes of the estuaries

Residual currents are the created by the mixing of fresh water and saline water Tidal currents have a two way flow Tidal currents have a continuous variation in velocity

Deserts

100

How are deserts defined in a modern way?

Comparing actual evapotranspiration with potential evapotranspiration

200

What is deflation and abrasion?

Deflation = Progressive removal of fine material Abrasion = Sandblasting action

300

Name all three effects that describe where deserts are located

As the air warms it can hold an increasing amount of water Rainshadow effect Many deserts lie along western coasts where the ocean water is cold. The coriolis force makes the prevailing winds push the warm surface water away from land. Instead the ocean next to the desert becomes really cold and the air's ability to hold moisture is diminished before it reaches the desert.

400

Describe a barchan without doing anything but hopping on one foot

That is correct!

500

What are exogenous, endoreic and ephemeral rivers? And name three causes of desertification in the sahel

Exogenous river = Rises in mountains beyond the desert margins. All year long. Endoreic = Endoreic drainage occurs where rivers terminate in inland lakes Ephemeral = Seasonally or after rainstorms Climate change, increase in animals, population growth

Rock types and landforms + Weather and Climate

100

Permeabilitet og porøsitet?

Permeabilitet = Afstrømningsmuligheder Porøsitet = Størrelse af hulrummene

200

Explain the terms 'Absolute humidity', 'Specific humidity' and 'Relative humidity'

Absolute humidity = g/m3 Specific humidity = g/kg Relative humidity = The amount of water vapour in the air at a given temperature expressed as a percentage of the maximum amount of vapour that the air could hold at that temperature.

300

Mention 3 out of the 4 ways condensation cooling may be achieved.

Radiation cooling: The ground loses heat rapidly through terrestrial radiation and the air in contact with it is then cooled by conduction. Advection cooling: Warm, moist air moves over a cooler and or sea surface. Ortographic and frontal uplift: Warm, moist air is forced to rise either as it crosses a mountain barrieror when it meets a colder, denser mass of air at a front. Convective/adiabatic cooling: Air is warmed in the daytime and rises in pockets as 'thermals'. As the air expands, it uses energy and so loses heat and the temperature drops. Because air is cooled by the reduction of pressure with height rather than loss of heat to the surrounding air, it is said to be adiabatically cooled.

400

Name the four distinctive layers of the atmosphere moving outwards from the Earth's surface.

Trophosphere (Temperatures fall by 6,4 degrees pr. 1000 m) Stratosphere (Temperatures rises due to the concentration of ozone) Mesosphere (Temp falls rapidly) Thermosphere (Temperature rises perhaps to 1500 degrees because of atomic oxygen)

500

Describe the DALR and SALR

The dry-adiabatic-lapse-rate, which is the rate at which an unsaturated parcel of air cools as it rises or warms as it descends, remains constantly at 9,8 degrees pr. 1000 m The saturated-adiabatic-lapse-rate can vary because the warmer the air the more moisture it can hold, and so the greater amount of latent heat released following condensation. The SALR may be as low as 4 degrees pr. 1000 m and as high as 9 degrees pr. 1000 m (Averages about 5,4 approx. 5 degrees pr. 1000 m).

Weather and Climate

100

What is an anabatic flow and a katabatic flow?

Anabatic = The sides of a valley is heated and an anabatic wind blows up the valley and the valley becomes conditionally unstable. Katabatic = During the evening the valley loses heat through radiation. The air begins to drain under gravity down the valley sides and along the valley floor as a katabatic wind.

200

What is the ITCZ and what are the Rossby waves?

The ITCZ is the Inter-Tropical-Convergence-Zone. Air is heated at the Equator rises and moves north through what is called the Hadley cell. When the air cools it returns over the surface. The Rossby waves are a meandering path of air around the earth formed by high pressure and low pressure. In the Rossby waves are the polar front jet stream, the subtropical jet stream and seasonally the easterly equatorial jet stream.

300

Explain the Coriolis force in your own way and answer the question why winds don't go around in circles.

Winds don't move in circles because of the balance between pressure gradient, the Coriolis force and friction.

400

What are the three main types of rainfall?

Convergent and cyclonic (frontal) = The meeting of two air streams in areas of low pressure. Orographic/relief = Warm maritime air is forced to rise by a coastal mountain barrier Convectional rainfall = Locally overheated air expands, rises and becomes unstable. The updraught is maintained by energy released as latent heat. Forms a cumulo-nimbus tower.

500

Explain the two major theories on rapid growth of water droplets.

Bergeron-Findeisen-mechanism = Water droplets and ice crystals exist together - Water droplets evaporate - Sublimates back onto the ice crystals - The ice crystals grow and splinters - And if air temperature rises above freezing point, it falls as water droplets The collision and coalescense process = Clouds without ice crystals as found in tropics, contain numerous water droplets of differing sizes. Different size, different velocity. Coalescence - and with a radius of 3mm - disintegration.

Random

100

What is flocculation?

When rivers like the Mississippi or the Nile reach the sea, the meeting of fresh and salt water produces an electric charge which causes clay particles to coagulate and to settle on the seabed - This is called flocculation

200

What is the name of the corkscrew flow belived to be responsible for moving material from the outside of one meander bend and depositing it on the inside of the next?

Helicoidal flow

300

Explain the term rejuvenation and eustatic uplift versus isostatic.

Rejuvenation is when sea-level falls in relation to the land. This movement causes land to emerge from the sea, steepening the gradient of the river and increasing the rate of fluvial erosion. Eustatic uplift = The global sea-level rises or falls because of melting ice sheets or water storaged on land in ice sheets Isostatic = A more local change in sea-level due to a depression or uplift of the earth's crust

400

What is a concordant and a discondant coast? And how has the use of sea defences changed over time?

Concordant = Rock structure parallel to the coast line Discordant = Coast cuts across rock structures Earlier = Sea walls, concrete breakwaters, groynes (trapping sand) Nowadays = Beach replacement, cliff stabilization (inserting pipes)

500

What are the four latin words Luke Howard used to describe the difference of clouds and what do they mean?

Cirrus = A lock of curly hair Stratus = A layer Cumulus = A heap or a pile Nimbus = Rain-bearing