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Glacier morphologies form a broad continuum, from the smallest niche glacier to the largest ice sheet. Apart from size, what is the main factor that differentiates ice sheets and ice caps from smaller glaciers?
A. Ice sheets and ice caps only ever occur at the poles
B. Ice sheets and ice caps only occur in high altitude environments
C. Ice sheets and ice caps are constrained by topography
D. Ice sheets and ice caps are unconstrained by topography
Which of the following terms is used to describe the loss of snow and/or ice from a glacier?
A. Erosion
B. Ablation
C. Abrasion
D. All of the above
Which of the following processes is the principal flow mechanism in cold polar glaciers?
A. Sublimation
B. Internal deformation
C. Basal sliding
D. Deformation of basal sediments
What term is used to describe the process by which glaciers move over small obstacles on their bed by the melting of ice under pressure and its subsequent transport and refreezing where the pressure is lower?
A. Regelation
B. Deformation of basal sediments
C. Sublimation
D. Calving
Glacial abrasion is a glacial erosion process whereby rock particles held within the basal ice are dragged over the bedrock. Which of the following are products of this process?
A. Striations in the bedrock
B. Small and rounded rock particles
C. Glacial flour
What is the term used to describe an oval-shaped hill, largely composed of glacial drift, which forms beneath a glacier or ice sheet and is aligned in the direction of ice flow?
A. Terminal moraine
B. Esker
C. Drumlin
D. Kettle
What is the term used to describe the instantaneous discharge of up to 50,000 m3 of water and debris from a glacier?
A. Ice sheet meltwater flood
B. Ice cap meltwater flood
C. Glacial lake outburst flood
D. Melt season discharge
Ice cores from ice sheets can contain an abundance of information on the dynamics of ice mass balance, paleo-climate, and paleo-environmental conditions. Currently, what is the length of the longest ice core record on Earth?
A. Approximately 1.8 million years
B. Approximately 800,000 years
C. Approximately 400,000 years
D. Approximately 200,000 years
Approximately what percentage of Earth’s freshwater is present in streams and rivers?
A. 0.005%
B. 0.050%
C. 0.500%
D. 5.000%
In which environments would a meandering river channel typically develop?
A. Environments with low slope gradients and erodible bank materials
B. Environments with high slope gradients and non-erodible bank materials
C. Environments with geological discontinuities, weaknesses and/or faults
D. Environments with variable discharge and/or sediment supply
River channels can also differ in the channel bed morphology. What channel bed morphology typically develops in steep mountain streams and rivers?
A. Pool-riffle sequences
B. Step-pool sequences
C. Sand dune and ripple sequences
Which of the following values is closest to the hydraulic radius of the theoretical river shown in Figure 1?
A. 0.006
B. 0.061
C. 0.305
D. 0.610
Figure 2: A device used for discharge measurement via the velocity-area method. For use in question 15. What is the name of the device shown in Figure 2?
A. Surface float meter
B. Electromagnetic current meter
C. Ott-type current meter
D. Acoustic Doppler Current Profiler (ADCP)
The types of waves generated by wind blowing across the sea-surface are determined by which of the following?
A. Fetch
B. Wind velocity
C. Duration of wind
For deep water waves, water depth is?
A. ≥ ½ wavelength
B. ≥ ⅔ wavelength
C. the reciprocal of wavelength
D. ≤ ½ wavelength
In wave analysis using linear or ‘Airy Wave Theory’, wave speed is calculated by which formula?
A. Δ = H / λ
B. f = 1 / τ
C. c = λ / τ
D. ω = 2 π / τ
The common centre of mass around which the Earth/Moon system rotates is?
A. Situated on the side of the Moon that faces the Earth and called the ‘Gravitational centre’
B. Situated between the Earth and the Moon and called the ‘Coriolis centre’
C. Situated within the Earth and called the ‘Barry centre’
D. Situated between the Earth and the Moon and called the ‘Centripetal centre’
Which of the following are examples of ‘Eulerian’ techniques of tidal current measurement?
1. A moored current meter 2. A sub-surface float 3. A freely drifting ocean buoy 4. An Acoustic Doppler Current Profiler
A. 2 and 3
B. 2 only
C. 3 only
D. 1 and 4