Every native of Cayman Brac knows where to go when their island is threatened with rising waters. Even to this day, Brackers will retreat to the bluff during hurricanes. 

But what if the sea level rose, not temporarily due to a hurricane, but permanently as a result of climate change?

While the 150 foot bluff gives Cayman Brac an average height above sea level of 56 feet, Little Cayman only has an average height above sea level of approximately nine feet and Grand Cayman is barely out of the water with an average elevation of only six feet.

According to a report released in 2010 by the National Climate Change Committee, titled The Green Paper: Towards a Climate Change Policy, even a moderate increase in sea level could have a considerable impact on these low-lying islands.

There goes the neighbourhood!
Based on the emission predictions provided in the International Panel on Climate Change Fourth Assesment Report, the Green Paper states that “an increase in sea level between 0.12 m (0.4 ft) and 0.80 m (2.6 ft), or roughly 0.14 to 0.91 cm per year, by 2100 is estimated for the Cayman Islands” if climate change remains unchecked.

In Grand Cayman, a rise in sea level of approximately 2.5 feet would impact over 1,000 buildings, and another half foot would increase the number of buildings affected to over 3,000.

Homes would further be affected by an increased risk of flooding due to the loss of mangrove wetlands that protect the coastline and act as a buffer against storm surge.

In fact, mangrove wetlands are already experiencing the effects of climate change:  The Green Paper report states that even the current rate of annual sea level increase, less than one inch per year, may compromise coastal mangrove buffers.

Bye-bye beach
A decrease in protective coastal mangroves and an increase in the sea level would impact beaches in the Cayman Islands significantly.

Not surprisingly, tourism would be expected to take a dive if the beaches of Grand Cayman were lost to rising seas.

Tourists, however, will not be the only ones missing the beaches. Already at risk because of increased coastal development, turtle nesting would be further impacted by the loss of beaches due to rising sea levels.
“Beaches in the Cayman Islands are low and narrow, so even a small rise in sea level would drastically reduce sea turtle nesting habitat,” said Dr. Janice Blumenthal, research officer with the Department of Environment. Coastal developments will only exacerbate the threat:
“In undeveloped areas, it is thought that beaches might be able to shift inland with rising sea levels,” Dr. Blumenthal said. “However, when buildings are constructed too close to the sea, beaches will not be able to shift and sea turtle nesting habitat will be lost.”

Marine degradation would not be restricted to the coast. Ocean temperatures are also rising and even minute increases in water temperatures can devastate marine life. Coral reefs, which are both natural protectors and tourist attractions would be particularly affected by warming, rising seas.