Embedded Files
New : N3/4 Science Course
Flooding
Flooding
Flooding occurs when water overflows from its usual location (river, lake, ocean etc.) onto land that is normally dry. Flooding occurs for a range of reasons:-
Flooding occurs when water overflows from its usual location (river, lake, ocean etc.) onto land that is normally dry. Flooding occurs for a range of reasons:-
- During heavy or persistent rain
- Ocean waves coming onshore during a storm
- Rapid snow melt
- Dams or levees breaking
Due to their destructive nature, flooding is very damaging to ecosystems and human developments, so flooding is classed as a 'Natural Disaster'.
Due to their destructive nature, flooding is very damaging to ecosystems and human developments, so flooding is classed as a 'Natural Disaster'.
Flooding is also made worse by human activities such as:-
Flooding is also made worse by human activities such as:-
- Deforestation - The removal of trees and other vegetation reduces the interception of water, which increases surface runoff. The lack of vegetation to bind the soil together can also increase the risk of landslips.
- Urbanisation - Increased unbanisation causes increased surface runoff by reducing infiltration (water passing down into the ground) due to the use of impermeable ground coverings such as concrete or tarmac.
- Climate Change - Human-accelerated climate change increases the risk of flooding due to increased or more intense rainfall. This is because warmer air can hold more moisture (for every 1℃ of warming, the atmosphere can hold 7% more moisture).
In Scotland, flood risk management and flood response is managed by SEPA (The Scottish Environment Protection Agency). It is SEPA's role to assess and manage the risk of flooding across Scotland by creating models of flood risk, which are used by the Scottish Government and the general public to plan for future flooding.
In Scotland, flood risk management and flood response is managed by SEPA (The Scottish Environment Protection Agency). It is SEPA's role to assess and manage the risk of flooding across Scotland by creating models of flood risk, which are used by the Scottish Government and the general public to plan for future flooding.
Using the SEPA Flood Map website, it is possible to generate layered maps showing the flood risk for any location in Scotland.
Using the SEPA Flood Map website, it is possible to generate layered maps showing the flood risk for any location in Scotland.
For example, the river Forth passes through Stirling before becoming the wider Firth of Forth. The city of Stirling areas of Raploch, Cornton and Causewayhead, along with the town of Bridge of Allan are built along both sides of the river, as shown in the map below:-
For example, the river Forth passes through Stirling before becoming the wider Firth of Forth. The city of Stirling areas of Raploch, Cornton and Causewayhead, along with the town of Bridge of Allan are built along both sides of the river, as shown in the map below:-
If a layer (light blue area) is added to the map to show the current medium level (0.5% chance of flooding per year) risk of river flooding due to the river Forth, the following map is generated:-
If a layer (light blue area) is added to the map to show the current medium level (0.5% chance of flooding per year) risk of river flooding due to the river Forth, the following map is generated:-
As can be seen by comparing the two maps, relatively few homes are currently within the medium risk flood areas, however, large areas of farmland are currently at risk of flooding, which is something that the land owners must take into account.
As can be seen by comparing the two maps, relatively few homes are currently within the medium risk flood areas, however, large areas of farmland are currently at risk of flooding, which is something that the land owners must take into account.
As part of their work, SEPA have also modelled the future flood risk across Scotland based on current climate prediction models. If a layer is added to the map to show the future (2080s) medium level (0.5% chance of flooding per year) risk of river flooding due to the river Forth, then the additional areas in dark blue will also be at risk of flooding:-
As part of their work, SEPA have also modelled the future flood risk across Scotland based on current climate prediction models. If a layer is added to the map to show the future (2080s) medium level (0.5% chance of flooding per year) risk of river flooding due to the river Forth, then the additional areas in dark blue will also be at risk of flooding:-
As can be now seen, the community of Cornton is predicted to be entirely at risk of flooding, as well as the southern half of Bridge of Allan. The Scottish Government, working with SEPA, will then use data such as this when planning for future flood defenses and other methods of reducing this risk in order to protect communities from damage.
As can be now seen, the community of Cornton is predicted to be entirely at risk of flooding, as well as the southern half of Bridge of Allan. The Scottish Government, working with SEPA, will then use data such as this when planning for future flood defenses and other methods of reducing this risk in order to protect communities from damage.
Drought
Drought
Drought is a prolonged period of abnormally dry weather, characterised by a significant drop in precipitation (rain, snow, etc. ) over an extended time, typically a season or more. This lack of water leads to shortages in water supplies, negatively impacting ecosystems, agriculture, and various human activities.
Drought is a prolonged period of abnormally dry weather, characterised by a significant drop in precipitation (rain, snow, etc. ) over an extended time, typically a season or more. This lack of water leads to shortages in water supplies, negatively impacting ecosystems, agriculture, and various human activities.
Droughts can range in severity and duration, from short, intense dry spells to multi-year events, and can occur in almost any climate, even in typically wet regions.
Droughts can range in severity and duration, from short, intense dry spells to multi-year events, and can occur in almost any climate, even in typically wet regions.
Droughts are becoming more common in certain areas, including Scotland, due to Climate Change.
Droughts are becoming more common in certain areas, including Scotland, due to Climate Change.
Water Scarcity in Scotland
Water Scarcity in Scotland
In 2022, the east of Scotland experienced its driest January since 1940. This was followed by lower-than-average spring and summer rainfall. This meant that by August, Water availability in the East of Scotland dropped to very low levels.
In 2022, the east of Scotland experienced its driest January since 1940. This was followed by lower-than-average spring and summer rainfall. This meant that by August, Water availability in the East of Scotland dropped to very low levels.
The Scottish Environment Protection Agency (SEPA) classes parts of Fife as having reached the highest level for water scarcity. Other parts of the country over that summer experienced similar conditions. These included the Tweed area, the Ythan, Dee and Don areas, and the Firth of Forth, Firth of Tay and the Almond and Tyne being graded at moderate scarcity.
The Scottish Environment Protection Agency (SEPA) classes parts of Fife as having reached the highest level for water scarcity. Other parts of the country over that summer experienced similar conditions. These included the Tweed area, the Ythan, Dee and Don areas, and the Firth of Forth, Firth of Tay and the Almond and Tyne being graded at moderate scarcity.
The video below shows a news report from August 2022:-
The video below shows a news report from August 2022:-
By mid-August the water levels in the river Eden in Fife dropped so low that SEPA suspended the right to river water abstraction (removing water from rivers to water crops) in the affected area. This risked the loss of crops in the area that required this water to survive, as well as triggering the possibility of water restrictions to homes:-
By mid-August the water levels in the river Eden in Fife dropped so low that SEPA suspended the right to river water abstraction (removing water from rivers to water crops) in the affected area. This risked the loss of crops in the area that required this water to survive, as well as triggering the possibility of water restrictions to homes:-
Page updated
Google Sites
Report abuse