Climate Exchange

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growing national populations well into the future will

require among other things stable economic growth

with few economic shocks such as those caused by

natural disasters.

Recent examples of weather and climate impacts

in the Caribbean

Losses associated with climate related disasters in the

English-speaking Caribbean can be extremely high and

in extreme cases exceed the national Gross Domestic

Product (GDP). For example, Hurricane Ivan in 2004

resulted in estimated financial losses on Grenada of

approximately 200 per cent of national GDP. A signif-

icant amount of this damage was due to high winds

causing damage to the housing stock, agriculture and

infrastructure. The passage of Hurricane Tomas over

Saint Lucia in October 2010 caused financial losses of

approximately US$600 million (approximately two-

thirds of the national GDP). Much of the estimated

losses were due to the extreme nature of the rainfall

associated with the system, with recorded rainfalls at

some locations in excess of 24 inches over a 24-hour

period. CIMH estimated the return period for this rain-

fall event to be greater than 180 years at some stations.

The extreme nature of the rainfall was not captured in

forecasts prior to the event and, as a result, the inherent

risks to the population and the infrastructure were not

fully assessed. The event caused significant impacts to

the John Compton Reservoir and associated distribu-

tion network which accounts for approximately 70 per

cent of the water consumed on the island. The event

exposed significant risks inherent in the water distribu-

tion system on the island.

While tropical storms inflict significant losses on

communities in the English-speaking Caribbean,

highly localized systems have caused significant damage

on some islands. On 12 April 2011, a poorly-forecast

localized rainfall event produced in excess of 200mm of

rainfall (with a peak 1-hour rainfall of 100mm) over the

mountainous terrain of northeast St. Vincent. The flash

flooding and landslides caused by the event inflicted

significant damage to the road and water networks

and the marine environment. The damage caused by

this event was approximately US$10 million. This

coming on the heels of the significant financial losses

(approximately US$90 million) inflicted on the island

by Tropical Storm Tomas six months earlier. Similar

events have also been experienced in other islands in

the English-speaking Caribbean.

In the late 1990s, a series of large landslides in western

Dominica dammed the Matthieu River to produce

‘Miracle Lake’. The formed lake and dam were peri-

odically, but not continuously, monitored. Early in the

morning of 28 August 2011, following several months

of above average rainfall over the island, the dam under-

went catastrophic failure releasing all of the stored

water and resulting in massive sediment and debris

flows in the downstream Layou River. This resulted in

significant impacts to businesses and residents down-

support from governments is not forth coming. As a result, innova-

tive approaches to sharing and utilizing the scarce human resources

in the region are essential.

Many English-speaking countries in the Caribbean have signifi-

cant coastal infrastructure that is prone to flooding and storm

surge. Flash flooding is common in coastal areas due to the steep

topography of most islands. Climate dependent industries, rain-fed

agriculture, tourism and related industries are the primary foreign

exchange earners and sources of employment in most English-

speaking Caribbean. The economies of the English-speaking

Caribbean are tightly integrated through trade and common finan-

cial institutions and businesses. As a result, economic shocks in one

country can have knock-on effects in other countries.

Population growth is still occurring on many islands leading

to increasing population densities at the national level. Within

countries, there is increasing rural to urban migration leading to

increasing demands for housing, water and sanitation services

among others in urban areas. This has resulted in increasing demand

for land and has driven the settlement on marginal lands includ-

ing landslide prone slopes and floodplains. Addressing the needs of

Image: CIMH

Miracle Lake Dominica: (top) 2008 prior to the dam failure and (bottom) August

2011 following the dam failure