CLIMATE CHANGE AND COASTAL VULNERABILITY IN SMALL ISLAND STATES

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CLIMATE CHANGE AND COASTAL VULNERABILITY IN SMALL
ISLAND STATES

• Leonard A. Nurse
• IPCC Coordinating Lead Author
• AOSIS Inter-Regional Preparatory Meeting for
  WSSD, January 7 - 11, 2002

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BACKGROUND AND CONTEXT

• Consensus of Marine and Coastal Scientists
• Global climate change will affect the physical,
  biological and biogeochemical characteristics of
  the oceans and coasts, modifying their ecological
  structure, their functions, and the goods and
  services they provide
• (IPCC-TAR, p. 345, Chapter 6, Coastal Zones and
  Marine Ecosystems).
• In the case of small islands, coastal
  vulnerability to climate change will be enhanced
  as a consequence of
• ?Sea-level rise
• ?Accelerated erosion
• ?Increased risk of storm flooding and
  inundation
• ?Elevated sea-surface temperatures

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COASTAL VULNERABILITY CONSEQUENCES FOR SMALL
ISLAND STATES

• Sea-Level Rise
• Although there are regional variations in the
  signal, sea level in the regions of the Small
  Island States is expected to rise by as much as
  5mm yr-1, for next 100 yrs, as a result of
  GHG-induced global warming. Some of the
  consequences will be
• ? Coastal Land loss, especially on atolls
  (Pacific and Indian Oceans) and low limestone
  islands (Caribbean).E.g. on Majuro Atoll (Marshal
  Islands), 65 ha (80 dry land) would be lost. In
  extreme cases, abandonment of some atolls and
  small islands may be the only practical option,
  given (i) elevation a.m.s.l., and (ii) physical
  size. E.g. Maldives, Indian Ocean.
• ?Loss of coastal infrastructure. Practically all
  critical infrastructure is located at or near the
  coast on islands.

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COASTAL VULNERABILITY CONSEQUENCES FOR SMALL
ISLAND STATES (contd)

• Beach Erosion
• Model runs and observed data consistently project
  that accelerated beach erosion will be an
  inevitable threat facing small islands. While
  much present-day erosion is man-induced (sand
  mining, construction in active beach zone,
  infringement of building set-backs, etc.),
  empirical studies show that SLR is a significant
  contributory factor.
• ?Higher Water Levels Higher Wave Amplitude
  Increased Wave Energy
• ? (a) In Trinidad, some beaches are retreating by
  as much as 2.0 m yr-1, where sea level has been
  rising at rate of 8-10 mm yr-1, during the past
  15 years. (b) In Fiji, where sea level has risen
  by 1.0-1.5 mm yr-1, beaches at Viti Levu and
  Taveuni have retreated by some 30.0 m since 1960.

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CONSEQUENCES OF CLIMATE CHANGE FOR SMALL ISLAND
STATES (contd)

• Storm Surge, Flood Risks and Inundation
• Although there is uncertainty about the future
  behaviour of tropical cyclones (hurricanes),
  flood risks and inundation from storm surge will
  be more severe.
• ?Even quantitatively small increases in relative
  sea level will have a disproportionate effect on
  flood levels (Non-linear relationship between SLR
  and inundation levels).
• ?Flood risk modeling (HADCM2, HADCM3, UKMO,
  1999) suggests that by 2080, numbers facing
  severe floods in the Caribbean, Indian and
  Pacific Ocean regions would be 200 times higher
  than if there were no SLR.
• ?Recent studies in Cuba (Perez et al. 1999,
  based on HADCM2), identified 98 coastal
  settlements with a total population exceeding 50
  000 persons, which would be completely inundated
  by a 1.0 m rise in sea-level.

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CONSEQUENCES OF CLIMATE CHANGE FOR SMALL ISLAND
STATES (contd)

• Coral reefs
• Observational evidence shows that periodic
  warming of the ocean surface, as occurs in El
  Nino years, leads to coral bleaching. The major
  events of the past 20 years occurred at times
  when ocean temperatures have been about 10 C
  higher than the summer maximum.
• ?Most intense episode on record occurred during
  1997-98 El Nino. On some islands gt90 of live
  reefs affected.
• ?Increasing atmospheric CO2 is being
  accompanied by similar increases in the oceans.
  This is expected to lead to a reduction in the
  rate of calcification of reef -building corals by
  between 14-30 by 2050.

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CONSEQUENCES OF CLIMATE CHANGE FOR SMALL ISLAND
STATES (contd)

• Tourism is a major revenue earner and generates
  significant employment. In addition the industry
  is almost entirely coastal. The impact of
  climate change on this sector will be both direct
  and indirect.
• SLR will disrupt the sector through loss of
  beaches, the threat to physical plant and vital
  infrastructure.
• The industry is also sensitive to other
  climate-related impacts, e.g. the loss of corals
  and other marine flora and fauna, which support
  the scuba diving industry.
• The highest temperature changes are occurring in
  the middle- and high-latitudes. A large of
  tourism is generated by the desire of visitors to
  escape the cold winters of the North. Milder
  winter temperatures in these markets could reduce
  the appeal of islands as tourist destinations.

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COASTAL VULNERABILITY REDUCTION IN SIDS GUIDING
PRINCIPLES AND ACTIONS

• Guiding Principles
• While we need financial and technical assistance
  to help us reduce our vulnerability to climate
  change, the response and overall strategy must be
  largely designed and implemented by SIDS.
• In designing our response and adaptation
  strategies we should seek, wherever possible, to
  draw on the experiences, expertise and relevant
  skills of SIDS and other appropriate developing
  countries (Promotion of South-South cooperation).
• We must also draw on indigenous skills and
  traditional knowledge that have helped to sustain
  many communities in the past.

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COASTAL VULNERABILITY REDUCTION IN SIDS GUIDING
PRINCIPLES AND ACTIONS (contd)

• BASIC REQUIREMENTS
• Inventory of Coastal Resources and Uses
• Define the nature of these resources (what are
  they Coral reefs? Seagrasses? Offshore sand
  reserves ? Minerals?)
• Location/ spatial distribution (Where are these
  resources?)
• Quantification of resources (How much?)
• Present status/trends Are the beaches eroding or
  accreting? Are fish stocks dwindling or
  expanding?

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COASTAL VULNERABILITY REDUCTION IN SIDS GUIDING
PRINCIPLES AND ACTIONS (contd)

• We Need Tools for Reducing Coastal Vulnerability
• Training in key areas of marine and coastal
  science e.g. oceanography, marine biology,
  fisheries biology, marine geology, coastal
  geomorphology (Capacity Building).
• Data collection and scientific research at the
  regional and local scales. For example, few SIDS
  have geodetic-controlled tide gauges or
  continuously recording marine meteorological
  stations (Research and Systematic Observation
  UNFCCC Article 5).
• Downscaling of GCMs to finer resolution (e.g. 50
  km, 25 km), to better facilitate meaningful
  vulnerability assessment at the island scale
  (Capacity building and Transfer of technology).