EQ4
Coasts
,REVISION – Geography Coasts – EQ4
Lesson 1 – Coastal Flooding and Climate Change
- Climate change will not increase the frequency of hurricanes globally.
- Some areas may experience an increase in the number of hurricanes
e.g. the North Atlantic has increased from 11 per year to 16 per year
between 2000 and 2013.
- Due to climate change, by the end of the 21st century, it is thought that
low pressure events, such as depressions and tropical cyclones will be
more intense with higher domes and more powerful waves
Domes = the rise in the sea level in the eye of a storm
- Hurricane winds may be 11% stronger and they could bring 20% more
rainfall by 2100
- The above will lead to more storm surges and more coastal flooding
- Even intensity predictions are dubious and although the strongest
hurricanes have increased in intensity over the past 2-3 decades in the
North Atlantic Ocean, in the pacific, there is no obvious change
- Climate change is likely to increase the risk of flooding due to more
intense storms and/or rising sea levels
- In many areas of the world, rising sea levels will be problematic by
2100, but manageable at any cost. Rises of 40-100cm will be managed
by sea defences in some places, but not everywhere.
- However, the IPCC has been predicted that, by 2100, hundreds of
millions of people will have been forced to abandon many coastal
zones worldwide, because of rising sea levels.
- This could lead to more environmental refugees in coastal areas
Environmental refugees
Communities forced to abandon their homes due to natural processes
2
, - Global costs of sea level rise could reach $1 trillion by 2050 with GDP
loss of 0.3-9.3% per year, potentially causing global recession
Areas most at risk
In general, Small Island Developing States (SIDS) like the Maldives, Tuvalu,
Barbados and Kiribati. They are often regarded as the most at risk of
coastal flooding and are likely to experience large amounts of
environmental refugees.
- Many of them are close to sea level - - - > Tuvalu’s highest point if
4.5m above sea level, and most land is only 1-2m above sea level
- Large numbers of people live and work on the coast - - - > 80% of
people in Seychelles occupy coastal areas
- Many are fringed by coral reefs, which as a natural coastal defence,
but rising ocean temperatures can destroy these due to coral
bleaching - - - > In the Marshall Islands, bleaching of unprecedented
severity is suspected to have hit most of the country’s 45 atolls and
islands
- Water supply is limited in these areas and they are at great risk from
saltwater incursion as Sea levels rise and groundwater is overused - - >
Low-lying small islands, rarely have surface water sources and are
heavily dependent on rainwater and groundwater, which will suffer
saltwater incursion.
- They have small and narrow economies based on tourism and fishing,
which are easily disrupted by rising sea levels. This also means they are
less able to cope and build defemces, as the sea level rise threatens
such a high % of their GDP - - - > The GDP of Kiribati is only $1,449.06
USD
Uncertainties
Tropical storms require a combination of factors to form, it is not just
global warming which influences them, so it is hard to work out how their
intensity and frequency will change.
3
Coasts
,REVISION – Geography Coasts – EQ4
Lesson 1 – Coastal Flooding and Climate Change
- Climate change will not increase the frequency of hurricanes globally.
- Some areas may experience an increase in the number of hurricanes
e.g. the North Atlantic has increased from 11 per year to 16 per year
between 2000 and 2013.
- Due to climate change, by the end of the 21st century, it is thought that
low pressure events, such as depressions and tropical cyclones will be
more intense with higher domes and more powerful waves
Domes = the rise in the sea level in the eye of a storm
- Hurricane winds may be 11% stronger and they could bring 20% more
rainfall by 2100
- The above will lead to more storm surges and more coastal flooding
- Even intensity predictions are dubious and although the strongest
hurricanes have increased in intensity over the past 2-3 decades in the
North Atlantic Ocean, in the pacific, there is no obvious change
- Climate change is likely to increase the risk of flooding due to more
intense storms and/or rising sea levels
- In many areas of the world, rising sea levels will be problematic by
2100, but manageable at any cost. Rises of 40-100cm will be managed
by sea defences in some places, but not everywhere.
- However, the IPCC has been predicted that, by 2100, hundreds of
millions of people will have been forced to abandon many coastal
zones worldwide, because of rising sea levels.
- This could lead to more environmental refugees in coastal areas
Environmental refugees
Communities forced to abandon their homes due to natural processes
2
, - Global costs of sea level rise could reach $1 trillion by 2050 with GDP
loss of 0.3-9.3% per year, potentially causing global recession
Areas most at risk
In general, Small Island Developing States (SIDS) like the Maldives, Tuvalu,
Barbados and Kiribati. They are often regarded as the most at risk of
coastal flooding and are likely to experience large amounts of
environmental refugees.
- Many of them are close to sea level - - - > Tuvalu’s highest point if
4.5m above sea level, and most land is only 1-2m above sea level
- Large numbers of people live and work on the coast - - - > 80% of
people in Seychelles occupy coastal areas
- Many are fringed by coral reefs, which as a natural coastal defence,
but rising ocean temperatures can destroy these due to coral
bleaching - - - > In the Marshall Islands, bleaching of unprecedented
severity is suspected to have hit most of the country’s 45 atolls and
islands
- Water supply is limited in these areas and they are at great risk from
saltwater incursion as Sea levels rise and groundwater is overused - - >
Low-lying small islands, rarely have surface water sources and are
heavily dependent on rainwater and groundwater, which will suffer
saltwater incursion.
- They have small and narrow economies based on tourism and fishing,
which are easily disrupted by rising sea levels. This also means they are
less able to cope and build defemces, as the sea level rise threatens
such a high % of their GDP - - - > The GDP of Kiribati is only $1,449.06
USD
Uncertainties
Tropical storms require a combination of factors to form, it is not just
global warming which influences them, so it is hard to work out how their
intensity and frequency will change.
3
