New Windmills - Pearson

Geography Ages 14-16 UK Years 10-11 US Grades 9-10
Edexcel International GCSE and
Edexcel’s own resource for the
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new for 2013
Revision Guide for
Geography!
This book provides complete coverage of the latest GCSE and Certificate in Geography
specification. It is written by Steve Milner and Mike Witherick, who are highly experienced
geography teachers and examiners.
The Student Book contains up-to-date information and statistics and current case studies taken
from a wide variety of international contexts.
Contains a free ActiveBook CD-ROM with a digital version of the Student Book, Geography
animations, PowerPoint presentations, a range of revision resources, fieldwork opportunities
and past questions.
Answers to Student Book questions available at www.pearsonglobalschools.com/
edexceligcseanswers.
Chapter 1: River environments
Section A:
The natural environment and people
1.1 The hydrological cycle
Fresh water is essential for life on Earth. This water is
constantly being recycled as it moves through a cycle known
as the hydrological cycle or water cycle. This is a global
circulation of water − it is a giant closed system (Figure 1.1).
This means that there is a fixed amount of water in the
system because water neither enters nor leaves the Earth
and its atmosphere.
Introduction
This chapter is about rivers. They are a vital part of the
global circulation of water. They are responsible for the
creation of landforms found throughout the world. They
are valuable to us because they supply much of the water
we use in our everyday lives. At the same time, because of
the risk of flooding, they can become hazards that threaten
people and their settlements.
interception
precipitation
clouds
snow
ice sheet
glacier
condensation
Chapter 1: River environments
solar energy
evapo-transpiration
infiltration
river
surface run off
percolation
evaporation
the sea
Figure 1.1: Stores and flows in the hydrological cycle
run off
lake/freshwater
surface store
soil rock
groundwater flow
Key
Stores
During the hydrological cycle, water is held in a number of stores and then moves
between them by means of a series of flows or transfers. The stores in the cycle are:
the atmosphere – here the water exists either as water vapour or as minute
droplets in clouds
the land – here water is stored on the surface in rivers, lakes and reservoirs. Water
is also taken in by plants and temporarily stored in vegetation. It is also stored below
ground in the soil or bedrock. This is known as the groundwater store. Generally
speaking, water exists in these stores in a liquid form. However, it can also exist in a
solid form as snow and ice, as for example in ice sheets, glaciers and snowfields.
Stores
Flows (transfers)
1
Sample page from Edexcel International GCSE Geography Student Book
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