Volume 29, Number 2, November 2015
Answers and instructions
Sea level quiz
This quiz (available to download separately from this issue’s GeographyReviewExtras) is designed for
classroom use. It could be used:

as a ‘starter’ activity to see what students already know about sea-level change or as a quiz at
the end of the topic

as a ‘team quiz’ just for fun, but to try and reinforce some key terminology and concepts
The quiz is marked out of 10.The answers are provided below along with some additional information
designed to promote further discussion in the classroom.
Answers
1
The correct answer is B, tides. These occur twice daily and are very predictable (unlike
waves). They alter local sea level by up to 16 m (the Bay of Fundy in Canada).
2
The correct answer is B, 3 mm. Measuring sea- evel is notoriously difficult as it changes
continually due to tides, waves and temperature. The land also moves due to isostatic changes.
Satellites are now used as well as fixed measuring points.
3
The correct answer is C, eustatic. This is the term for a change in the volume of water in the
oceans and is a global change. Isostatic is the term for a change in land level (up or down) which has
only a local affect, e.g. subsidence of a river delta.
4
The correct answer is C, melting of sea ice. Floating sea ice such as that which occurs in the
Arctic Ocean is already displacing its own weight of water, so melting the ice has no effect on sea
level. Recent research does suggest it has a tiny effect, as melting sea ice dilutes ocean salinity
leading to a decrease in density and a tiny rise in sea level.
5
The correct answer is B, 0.98 m or 98 cm. This is roughly the height of most light switches in
UK homes. This is also the upper limit of the IPCC estimates, the lower limit is mere 28 cm (a
classroom ruler). The large range of estimates makes it difficult to plan protection for vulnerable
coasts.
6
The correct answer is D, isostatic rebound (or isostatic readjustment). It is a result of the
removal of the weight of ice sheets at the end of the last glacial period. The ice mass depressed the
land surface by hundreds of metres, and over the last 12,000 years the land has slowly rebounded.
This is still happening in Scotland by up to 2 mm per year in some places, so does not quite ‘keep
pace’ with eustatic sea-level rise.
7
The correct answer is A, thermal expansion. It appears to contribute about 50% of the total
annual rise, with the Greenland ice cap, glaciers on land and Antarctica making a smaller contribution.
Philip Allan Publishers © 2015
www.hoddereducation.co.uk/geographyreview
8
The features on the left in the background are raised beaches (B) (and between them fossil
cliffs) on the Fife coast in Scotland. The flat platforms represent former beach levels produced as
isostatic rebound has lifted the coastline out of the sea.
9
The correct answer is C, −120m. Sea levels were very much lower during the last ice age. Big
Ben in London is 96 m high by comparison. This means there was no English Channel, and no North
Sea during the ice age, because sea levels exposed shallow continental shelf seas.
10
The correct answer is D, they are all likely to disappear. Both Tuvalu and the Maldives are
island chains less than 2 m above sea level so very vulnerable to sea-level rise. Miami has been
declared (by Swiss Re) the city most vulnerable to the combined effects of storms and sea-level rise.
The Sundarbans are a low-lying mangrove swamp area straddling the coastal border between India
and Bangladesh. 75% of this area is likely to disappear by 2100.
This resource is part of GEOGRAPHY REVIEW, a magazine written for A-level students by subject experts.
To subscribe to the full magazine go to: http://www.hoddereducation.co.uk/geographyreview
Philip Allan Publishers © 2015
www.hoddereducation.co.uk/geographyreview