Climate change impacts within the Dutch Caribbean

The most recent climate change predictions for the Caribbean region (2013/2014) by the Intergovernmental Panel on Climate Change (IPCC) are alarming and suggest that the islands of the Dutch Caribbean will go through profound environmental changes within the next century.

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Under an intermediate low-emissions scenario, the IPCC has made the following projections for the Caribbean Region by the end of this century:
an increase in air temperature of 1.4°C;

  1. a decrease in rainfall of 5 to 6%;
  2. an increase in the frequency and intensity of extreme weather events, including a 66%
  3. increase in hurricane intensity; and
  4. a rise in sea level of 0.5 to 0.6m as a result of thermal expansion of water and glacial melt (1).

These climate change predictions are especially worrying in the context of an already visible warming trend. Average temperatures in the Netherlands Antilles have risen steeply over the past 40 years according to recent data (2). In Curaçao, research carried out by the Meteorological Department found that over the past few decades the island has progressively experienced more hot days and fewer cold nights (3). Because the islands of the Dutch Caribbean form two geographically distinct groups separated by more than 900 km of open water, it is expected that climate change will not impact these two island groups in the same way.  Aruba, Bonaire and Curaçao are located in the Southern Caribbean, an area that is predicted to become warmer and drier, with longer seasonal dry periods. Saba, St. Eustatius and St. Maarten, which are located in the Northeast Caribbean and therefore within the Caribbean hurricane belt, are predicted to experience an increase in rainfall during the wet season (November–January) as well as more frequent and violent tropical hurricanes.

While the full extent of climate change’s impact on different ecosystems and species is still poorly understood, we can expect it to be significant. All of the Dutch Caribbean’s marine and terrestrial ecosystems and the species that inhabit them will be affected, to varying degrees. Coral reefs are predicted to be especially vulnerable as higher ocean temperatures and ocean acidification will undoubtedly result in mass coral bleaching events among other things.

Overview of possible impacts of climate change within the Dutch Caribbean
(Adapted from: Debrot, A.O and Bugter, R. (2010) Climate change effects on the biodiversity of the BES islands. Alterra-report 2081, IMARES-report C118/10)

Biodiversity

Coral Reefs

  • Ocean acidification and increased SST are projected to trigger mass coral bleaching.
  • IPCC projects that severe mass coral bleaching events will likely occur in the Caribbean by 2074.
  • Increased storms and associated rainfall will cause an increase in terrestrial run-off and resulting sedimentation.
  • Stronger and more frequent hurricanes and tropical storms will cause more damage to reefs with less time to recover in between.
  • Ocean acidification will impact the formation and maintenance of reefs as it reduces coral growth and increases the rate of dissolution of reefs.
  • It is believed that an increase in reef diseases in the past decades is linked to temperature stress, meaning reef diseases will become more and more prevalent.

Coastal Ecosystems (mangroves, seagrass beds, saliñas, beaches)

  • Inundation of coastal habitats resulting from sea-level rise and higher wave energy may result in the inundation of certain coastal habitats.
  • Sea-level rise will threaten the functioning of Bonaire’s flamingo feeding areas due to a too large inflow of seawater.
  • Sea-level rise will threaten mangroves as salinity levels will become too high and the water depth too deep.
  • Seagrass beds will be under threat from an increased SST and changes in salinity.
  • Sea level rise and increased rainfall will accelerate the rate of beach erosion.

Terrestrial Vegetation

  • Increases in air temperatures and hurricane intensity directly threaten hilltop and mountain vegetation and flora. Hurricanes cause physical damage and higher temperatures will result in soil loosing its humus retention capability.

Invasive Species and Diseases

  • Local species will be weakened from the other impacts of climate change and therefore have less resistance to invasive species.
  • Increased air temperatures may increase the occurrence of tropical diseases.

Ecological Processes

Changed timing of interactions

  • Increased temperatures may result in critical changes in the timing of interactions between species (for example between pollinators and seed dispersers and their host species.)
  • Plants may fruit and flower at a different time, compromising species that cue reproduction periods to availability of certain food – this may compromise their reproductive success.

Shift in ecological zones

  • Some species may move north to avoid rising temperatures.

Change in ocean currents

  • Current speed or/and direction may be impacted by climate changes.
  • Changes in currents may have unprecedented effects on the ecosystems and species that depend on them and the ecological connectivity between islands (e.g. dispersal of coral larvae via currents).

Socio-Economic

Tourism

  • The economy of Dutch Caribbean Islands is largely dependent on tourism; in 2012, the incoming tourism accounted for a direct contribution to Bonaire’s Gross Domestic Product (GDP) of approximately 16.4% (4)
  • Increase in storms and hurricanes may result in tourists’ perception of destination as unsafe.
  • Beach erosion and coral bleaching may negatively impact perceptions of destination attractiveness.
  • Risk of damage to coastal resort properties by violent hurricanes and other storms.
  • Risk of damage to tourist attractions; on Bonaire, beach erosion due to loss of shallow reefs leaves historic plantation buildings like those of Washington Slagbaai Park vulnerable.
  • Risk of freshwater shortage due to salinization of groundwater.

Fisheries and agriculture

  • Salinification linked to sea-level rise will have a huge negative impact on agriculture.
    Damage to reefs and changes in ocean currents are just a few climate change impacts that will seriously threaten local fisheries.

References

  1. IPCC (2013) The IPCC’s Fifth Assessment Report: What’s in it for Small Island Developing States? Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA.
  2. NU. CEPAL. Sede Subregional para el Caribe (2011) An assessment of the economic impact of climate change on the tourism sector in Curaçao.
  3. The Government of Curaçao (June 2014) National Report of Curaçao for The Third International Conference on Small Island Developing States. Apia, Samoa, September 1–4, 2014.
  4. CBS (2015) Trends in the Caribbean Netherlands 2015

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