The Caribbean Environment
Ecologically, the Caribbean lies within a tropical hurricane belt, covers nearly two million square kilometers, averages 2,200 metres in depth (and plunging to 7,100 metres in the Cayman trench), receives run-off from eight major river systems, contains well developed seasonally stratified marine waters, and at least one dead zone. The islands themselves vary in size from 91 square kilometers in Anguilla to Cuba’s 110,860 square kilometers, with highly varied topographies and geology, including low-lying limestone and coral reef atolls, volcanic outcrops and diverse local flora and fauna.
Caribbean coastal ecosystems are a mixture of mangrove, sea-grasses and coral reefs while the terrestrial ecosystems are made up of thirty-four ecoregions where many plant and animal species are unique to these islands–they don’t naturally occur anywhere else on Earth.
The freshwater supply is highly varied, from Jamaica ranked as the small-island developing state (SIDS) with the most abundant freshwater supply, to Barbados being one of the world’s most arid countries.
The experience of environmental change and challenges is more pronounced in SIDS compared to the rest of the world. This is due to their small physical scale, geographic isolation, unique biodiversity, exposure to natural hazards and disasters, high population growth coupled with out-migration and significant seasonal in-migration from tourism, limited resource base, remoteness from global markets and small economies of scale.
This means that the issue of climate change poses a significant and unique challenge in the Caribbean.
Climate Change Impacts in the Caribbean
While it is a region that produces marginal emissions relative to the rest of the world (less than one percent of global greenhouse gas emissions), it faces a disproportionate brunt of the effects of global warming and climate change.
These threats include:
- Sea level rise: In the Caribbean, the average sea level is expected to rise by 1.4 m (4.5 feet) by the end of the century, translating to 5mm of sea level rise every year. The rise in sea level could impact coastal communities of the Caribbean if they are less than 3 metres (10 ft) above the sea. This is of particular concern as most Caribbean cities and towns are situated near the coast.
- More frequent and intense hurricanes: Average land and ocean surface temperatures in the Caribbean are projected to increase by 1.0 to 3.5℃ by 2100. Hurricanes are fueled by warm ocean temperatures, so our increasing average temperatures will lead to more intense and frequent extreme weather events like storms and hurricanes in the region.
- Droughts and heavy flooding: The change in precipitation, or rainfall, over the region will vary widely from -14.2% to +13.7% in the next two decades alone. This is due to the dynamic weather circulation patterns across the Caribbean, resulting in the Northern Caribbean experiencing more heavy rainfall events and flooding, and the southern Caribbean experiencing an increase in consecutive dry days resulting in droughts.
- Coastal erosion: One of the consequences of rising sea levels, coastal erosion describes the process by which coastlines are worn away by waves, currents and tides. While some erosion is natural, climate change and rising sea levels exacerbate the situation, eroding beaches, cliffs and other coastal landforms. It is estimated that a 0.5 meter rise in sea level will result in 38% of beach loss in the Caribbean.
- Saltwater intrusion into groundwater systems: Saltwater intrusion involves the movement of saline water into freshwater aquifers. Freshwater, being less dense than saltwater, typically lies above the saltwater in coastal aquifers. The boundary between the freshwater and saltwater is known as the “interface.” When the balance between these two is disrupted, saltwater can encroach into regions typically occupied by freshwater. Higher sea levels increase the pressure on the saltwater side of the interface, pushing saltwater further into freshwater aquifers, degrading the local water supply, damaging crops, and disrupting inland freshwater ecosystems.
- Coral bleaching: Coral bleaching is a stress response of corals that leads to the loss of their vibrant colors and can significantly impact reef ecosystems. It occurs when corals are stressed by changes in conditions such as temperature, light, or nutrients. The primary cause of widespread coral bleaching events is rising sea temperatures due to global climate change. This in turn destroys critical habitats for many species of fish and marine life, reduces the capacity of reefs to protect coasts from erosion, and causes economic losses for local communities dependent on fishing and tourism.
- Ocean acidification: Ocean acidification refers to the ongoing decrease in the pH of the Earth’s oceans, caused primarily by the uptake of carbon dioxide (CO2) from the atmosphere. Due to the burning of fossil fuels, deforestation, and other human activities, our oceans have had to absorb more CO2 than usual. When CO2 is absorbed by seawater, a series of chemical reactions occur that lead to a decrease in the water’s pH, making it more acidic. This has negative impacts for marine life, coral reefs, food webs and human economies. These warmer and more acidic waters also feed the growth and spread of more sargassum seaweed than we can handle.
- Adverse effects on crops and fisheries: Climate change significantly impacts agriculture and fisheries, affecting food security globally. From increased temperatures and CO2 levels, altered rainfall patterns, pest and disease proliferation and soil degradation, climate change can have massive negative impacts on crop yields. Fisheries are at risk due to the temperature change, ocean acidification, loss of coral reefs, and changes in freshwater and ocean currents.
- Increases in vector-borne diseases: These diseases are infections transmitted by the bite of infected arthropod species, such as mosquitoes, ticks, and fleas. Examples include malaria, dengue fever, Zika virus, Lyme disease, and West Nile virus. The increase in vector-borne diseases due to climate change is primarily attributed to the expansion of the habitats suitable for vector species and the extension of transmission seasons. Higher temperatures accelerate the life cycles of these insects, and both increased rainfall and drought can lead to more standing water that provide ideal breeding grounds for mosquitoes.
Conclusion
The potential impacts of climate change are vast in our Caribbean region, affecting coastal and inland ecosystems, increasing incidences of adverse weather, worsening public health, and damaging the economy. The costs of the damage of the challenges listed above will be insurmountable if we don’t take action at home and globally to reduce greenhouse gas emissions, and ready our communities to adapt to a changing planet.
Author: Alicia Richins
Sustainable Impact Strategist | SDG Champion | Climate Justice Advocate | Climate Futures Writer
