Hurricanes and tropical islands

One does not exist without the other it seems. Dr Anjani Ganase reminds us of the special relationship that comes with being small islands in the vast oceans that generate these storms.

The Bahamas sits in the hurricane belt and has one of the highest, if not the highest, history of hurricane for the Caribbean. Its infrastructure and society is adapted for hurricanes. Yet, the devastation that Dorian has left is another reminder of how much we underestimate the impacts of climate change and how much we (humans) are lagging in preparing ourselves for the future of a changed climate. The only other Category 5 hurricane to pass directly over in the Bahamas in recent times was Hurricane Andrew, which had maximum wind speed of 265 km/hour and passed over Bahamas within 12 hours. Dorian, on the other hand, had maximum wind speed of 295 km/hour and sat over the Bahamas for over two days! The destructive winds, rainfall and storm surge devastated communities and this is only the most obvious impact. Here are some less obvious impacts that will emerge in the coming weeks, months and years following a hurricane.

Photo Caption: On Monday, Sept. 2, 2019, GOES East captured a view of the Category 5 storm, Hurricane Dorian, over Grand Bahama where it unleashed destructive hurricane-force winds, along with 200 mph gusts. Photo Source NOAA

Human health

A complete loss of infrastructure means the loss of running water, electricity, shelter, clean clothes, food, medicine and medical services. These are daily necessities that provide a standard of living and health to withstand communicable illnesses and maladies. The number of physical injuries is expected to sky rocket in the weeks following a hurricane, which is typically related to the hurricane itself but also to rescue and salvaging process. Infectious disease outbreaks are associated with the displacement and relocation of families to temporary shelters with sometimes overcrowding conditions. Gastrointestinal illnesses, cholera, diarrhoea, cellulitis and skin infections tend to peak in the two weeks after a hurricane and can persist for months after. There are also increases in poisoning cases that require medical attention following storm damage because of poorly managed dispensation and use of carbon fuels in the absence of a grid power supply - carbon monoxide poisoning and gasoline exposure. 

What about those with existing medical conditions? The halting of medicines and medical services, for example dialysis machines, after a hurricane can be devastating. Following a hurricane, the cases related to diabetic foot, cardiovascular illness, increases up to 16 months because of the lack of a steady supply of medicine and attendance. Accompanying the physical distress is the psychological distresses that may have longer lasting effects on persons. Post-traumatic stress disorder (PTSD), depression and anxiety, especially when associated with a physical illness related to the hurricane can last months and even years especially on the anniversary of the event. 

Island Ecosystems

Island nations, such as Tobago and the Bahamas, rely on the environment resources – beaches, reefs, mangroves, seagrass meadows and rainforests - to sustain livelihoods. The unique and extensive coastline of Bahamas is the major resource for tourism and its destruction will have a huge impact on the economy. Beaches, coral reefs, mangrove and seagrass all bear the brute force of the ocean during a hurricane. Storm surge and wave action turn coastal waters into a hostile place, not just for those of us that live near to the coast but also for the marine organisms that live beneath the surface. The storm surge generated from a Category 5 hurricane heading towards land can pummel the coast and penetrate miles inland. Wave action will turn coral reefs into rubble, rip up seagrass beds and topple mangrove tress through the intense wave action. Water movement stirs up the sand, which then scours other corals, seagrasses and resident marine life, eventually smothering benthic organisms. Larger more mobile marine fish may be able to relocate to deeper waters or offshore during a hurricane, but many reef fish and invertebrates are likely to be killed by the severe water movement and sedimentation especially exceptionally stirred up water that may clog their gills. Water temperatures and salinity conditions tend to shift dramatically because of large inputs of freshwater from the hurricane or the push of deeper, saltier waters up from offshore by storm surge. These sudden changes in conditions may also contribute to fish mortality during a hurricane. Following a hurricane, the loss of coral life results in algal blooms over the reef substrate, but there may also be disease outbreak among the remaining corals because of changes to the water quality. 

Seagrasses and mangroves can regrow providing that the hydrology of the areas are not significantly disturbed, otherwise mangrove forest may be replaced by intertidal mudflats in cases where the conditions become unsuitable for mangrove regrowth. Eventually with the return of fish and invertebrates to graze on the algae, coral can regrow from recruitment from neighbouring reefs, and from surviving colonies. Recovery from hurricanes can take years, but it also depends on how well we manage other stressors pollution and our fisheries. In the past many Caribbean reefs have shown little recovery up to eight years following a hurricane disturbance, and this was related to the impairment of reefs to be able to recover because of local stressors. In Bahamas, the conch and lobster fisheries are heavily dependent on the state of the seagrass meadows, which will take years to recover. Consider that these ecological processes will take decades to recover; it is also likely that Bahamas may be impacted again by hurricanes repeatedly in the years that follow. Innovations are urgently needed to manage subsequent disturbances. 

Island nations are especially vulnerable to the impacts of climate change, despite not being major contributors to climate change. In our Caribbean island nations, climate change adaptation must be made a priority for citizens. Citizens need to hold their governments accountable for pro-active investment into programmes for climate change adaptation. They must include infrastructure solutions, the use of alternative energy, disaster preparedness and conservation solutions to allow for ecosystems to recover efficiently. Adaptation programmes must also include plans to change our lifestyle and mindset on how we use energy and treat nature. 

Caribbean people also need a unified voice to put pressure on the biggest contributors to carbon emissions, countries like the USA, China and Europe, to maintain their goals and to hold them accountable. Bahamas will have to rebuild and for a country that was already built for hurricane even further innovation is needed to withstand a potential new norm of climate change. Hopefully, they will not have to do this alone. 

Let us think about Bahamas in this time of need. Support and supply them, not just over the next few weeks, but over the next few months and years. Let us islands unite to protect the ocean and our places as outposts of ocean. 

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