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Sea Level Rise

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Sea Level Rise

According to the National Geographic article Sea Level Rise accessed in June 2014, "The rise in sea levels is linked to three primary factors, all induced by this ongoing global climate change:

Thermal expansion: When water heats up, it expands. About half of the past century's rise in sea level is attributable to warmer oceans simply occupying more space.

Melting of glaciers and polar ice caps: Large ice formations, like glaciers and the polar ice caps, naturally melt back a bit each summer. But in the winter, snows, made primarily from evaporated seawater, are generally sufficient to balance out the melting. Recently, though, persistently higher temperatures caused by global warming have led to greater-than-average summer melting as well as diminished snowfall due to later winters and earlier springs. This imbalance results in a significant net gain in runoff versus evaporation for the ocean, causing sea levels to rise.

Ice loss from Greenland and West Antarctica: As with glaciers and the ice caps, increased heat is causing the massive ice sheets that cover Greenland and Antarctica to melt at an accelerated pace. Scientists also believe meltwater from above and seawater from below is seeping beneath Greenland's and West Antarctica's ice sheets, effectively lubricating ice streams and causing them to move more quickly into the sea. Moreover, higher sea temperatures are causing the massive ice shelves that extend out from Antarctica to melt from below, weaken, and break off."

The article goes on further to discuss the consequences of sea level rise:

"Consequences

When sea levels rise rapidly, as they have been doing, even a small increase can have devastating effects on coastal habitats. As seawater reaches farther inland, it can cause destructive erosion, flooding of wetlands, contamination of aquifers and agricultural soils, and lost habitat for fish, birds, and plants.

When large storms hit land, higher sea levels mean bigger, more powerful storm surges that can strip away everything in their path.

In addition, hundreds of millions of people live in areas that will become increasingly vulnerable to flooding. Higher sea levels would force them to abandon their homes and relocate. Low-lying islands could be submerged completely."


Impacts of Sea Level Rise on the Caribbean Region

According to the Quantification and Magnitude of Losses and Damages Resulting from the Impacts of Climate Change: Modelling the Transformational Impacts and Costs of Sea Level Rise in the Caribbean (Full Report) produced by Caribsave  and the United Nations Development Programme (UNDP) in 2010, the impacts of 1m SLR on the CARICOM nations include:

"A 1m SLR would displace an estimated 110,000 people in the CARICOM nations.118 Bahamas has the highest percentage of national population affected (5%) because of greater impacts on urban areas (3% inundated). Other nations with substantive populations affected by a 1m SLR include St. Kitts and Nevis (2%) and Antigua and Barbuda (3%).

Tourism and agriculture revealed key vulnerabilities for some nations. Considering its very close proximity to the coast, it is not surprising that tourism was by far the most vulnerable major economic sector. This is a key finding, as tourism is a major part of the economies of Caribbean nations and has been overlooked in most previous assessments of the impacts of SLR on national economies. The World Travel and Tourism Council (WTTC)119 estimates that tourism represents 14.8% of GDP and 12.9% of employment (approximately 2 million jobs) in the Caribbean, and the importance of tourism for individual island economies can be much higher (GDP in 2002).120 Antigua and Barbuda 72%, St. Lucia 51%, The Bahamas 46%, Barbados 37%, St. Vincent and the Grenadines 29%, Jamaica 27%, St. Kitts and Nevis 25%, Belize and Grenada 23%, Dominica 22%. Of the
673 major resorts in the CARICOM countries inventoried for this analysis, 149 are at risk to 1m SLR. Beaches are critical assets for tourism in the Caribbean and a much greater proportion would be lost to inundation and accelerated erosion well before resort infrastructure was damaged.

Major resort properties were at significant risk to 1m SLR in various countries, notably, Belize (73%), St. Kitts and Nevis (64%), Haiti (46%), Bahamas (36%) and Trinidad & Tobago (33%). Such impacts would transform coastal tourism in the region, with implications for property values, insurance costs, destination competitiveness, marketing and wider issues of local employment and economic well-being for thousands of employees. In some cases impacts to particularly high-profile tourism properties, such as the projected flooding of parts of Paradise Island in The Bahamas (Figure 23) would have a disproportionately large economic impact.

Also of importance to tourism, but also the wider economy in each nation, is the vulnerability of key transportation infrastructure. SLR of 1m inundated a total of 21 out of 64 airports within CARICOM. The vulnerability of airports was highest in Grenada, where the runway area will become completely inundated. More than 550km of roads were projected to be inundated by 1m SLR in CARICOM nations. The road networks were at greatest risk in The Bahamas (14%), Dominica (14%) and Guyana (12%). Seaports would also be affected, with the surrounding port lands of 35 out of 44 ports in CARICOM inundated by 1m SLR unless
protected by coastal structures.

Agriculture was found to be less vulnerable than the tourism industry, however the estimated impact of 1m SLR is still important for food supply, security and livelihoods. Estimated total agricultural land loss was highest in The Bahamas (6%), Dominica (5%) and Haiti (3%). The loss of crop and plantation lands (the highest value agricultural lands) was highest in The Bahamas (3%), while other islands experienced losses around 1%."

The report also provides a summary of the most recent projections of global SLR over the 21st Century and compares these newer studies to the IPCC AR4 projections and continuation of current trends. See image below.

Summary of global sea level rise projections for 21st Century

Be sure to peruse the entire report, the summary report, and the key points and summary for Policy Makers.


was written by

Based on interviews with Dr. Kenrick Leslie, Executive Director of the CCCCC, and Dr. Ulric Trotz, the CCCCC's Deputy Director and Science Advisor, the following was stated about Sea Level Rise within the Caribbean:

“In 50 years, if the [models] are correct, the entire [Caribbean] landscape will be changed,” says Ulric Trotz, the CCCCC’s deputy director. “Our beaches will have disappeared, our coastal areas eroded, our infrastructure degraded. It would certainly wreak havoc on the way we live.”

Trotz recently co-authored an Inter-American Development Bank report that warns of as much as 1,200 square miles of Caribbean coastal land lost; half the Caribbean Community’s major tourist resorts damaged or destroyed by sea rise, surge or erosion; and scores of sea turtle nesting beaches wiped out. Even the airports that receive tourists could be affected.

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