GCSE factors affecting flooding
Terms in this set (14)
when river level gets too high and spills over banks.
river level increases when discharge increases, more water is in channel.
of river flooding include changes to land use, urbanisation and deforestation
of river flooding are natural, such as relief, precipitation, soil and rock type, vegetation cover
Long steady prolonged rainfall
will produce rivers which rise slowly but can flood
Heavy short showers
can cause rivers to rise quickly and burst their banks.
Precipitation is often stored as snow during cold snaps. When temperature warms and that snow melts many days' worth of precipitation can end up in rivers and cause flooding.
reduce the amount of infiltration of water into the ground, this water can then flow quickly down to rivers as overland flow
Gentle slopes or flat land
allow water to penetrate into the soil and increase lag times.
Vegetation type and coverage
reduce river levels & increase lag time, with forests intercepting more rainfall than grasses.
Impermeable soils and rocks
such as clay or shale do not allow water to infiltrate, this forces water to run off reducing river lag times and increasing flood risk.
allow water to infiltrate into them and reduce river levels
can cause flooding because many of the surfaces in towns and cities are Impermeable.
The urban drainage system
Is designed to move water from the surface into underground pipes and away from urban areas which have value.
The removal of trees can increase soil erosion, reduce interception and increase flood risk
THIS SET IS OFTEN IN FOLDERS WITH...
GCSE River long & cross profiles
GCSE River Erosion Landforms
GCSE River Deposition Landforms
GCSE river processes
OTHER SETS BY THIS CREATOR
RMeTS annotated air masses task
RMeTS Air Masses version 2
UK Geography Year 9
Location of World Megacities (2018)