Climate Sense

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which lost the majority of its nutmeg industry following

the passage of Hurricane Ivan in 2004.

The Caribbean climate is valued by people from around

the world because of its positive health benefits, but said

climate is also responsible for potential negative health

effects. Vector-borne diseases represent one climate related

health concern for which a body of literature on the subject

exists. Joint research by the University of the West Indies

(UWI) Climate Studies Group Mona and the Caribbean

Epidemiology Centre on the epidemiology patterns of

dengue fever in the Caribbean concluded that in the

region the illness has a well-defined climate seasonality. In

particular, it was observed that warm and dry conditions

followed by rainfall appear to enhance the probability of

the epidemic occurring. The research also showed a strong

correlation between fever outbreaks and the occurrence of

ENSO events. Based on these findings, the research teams

proposed a moving average temperature index to identify

periods where the potential for dengue fever outbreaks may

be high.

Other health concerns that may be attributable to

seasonal climate tendencies include asthma, bronchitis,

respiratory track infections and diarrhoeal illness. Personal

injury rates on average across the Caribbean also tend to

be higher during the North Atlantic hurricane season. Of

the ailments listed, however, asthma has received particular

attention.

Depradine and Lovell’s paper demonstrated that

in Barbados, incidences of asthma were greatest along the

eastern portion of the island and that in general asthma cases

peaked during the rainy season when there is an increase

in moulds, spores, pollen and other chemical aeroallergens

in the atmosphere. The study further showed that peak

incidences of asthma occurred approximately three to four

weeks after a peak in atmospheric moisture.

Increases in

the number of cases and severity of occurrences of asthma

have been linked to occurrences of Saha Dust over the

region. However, there is a growing body of literature that

is challenging the assertion.

Existing seasonal forecasts for the Caribbean region

As already discussed, there is a distinct correlation

between seasonal characteristics in the Caribbean and

socioeconomic development and productivity. Given

this, and the region’s vulnerability to climate related

hazards, improved efficiency and resilience in socio-

economic sectors must be achieved through the use of

seasonal climate forecasts, which may cover periods

ranging from two weeks to several months. Critical

atmospheric variables considered in such forecasts

include surface temperatures, precipitation, and speed

and direction of wind. Several seasonal climate forecasts

are issued for the Caribbean region annually. The annual

‘North Atlantic Seasonal Hurricane Forecast’ offered by

Professor William Gray of Colorado State University is

perhaps the most well known and anticipated climatic

forecast due to its perceived socioeconomic implications

for the Caribbean region. These annual predictions have

a significant impact on the financial positions and risk

that insurance companies assume for any given year.

between March and May. The eastern Caribbean exhibits a unimodal

rainfall regime with the majority of rainfall occurring during the North

Atlantic hurricane season, which is associated with unstable air masses

producing significant precipitation.

Guyana exhibits a bimodal rainfall patternwith the primary rain season

occurring from December through to February. It is during this season

that extensive flooding was observed in Guyana in the latter part of

December 2004 to February 2005. The secondary rainy season inGuyana

extends fromMay to August.

Existing climate patterns in the Caribbean may be modified as a result

of global climate change, changing land use and increasing industrializa-

tion. Current observations and outputs from global and regional climate

models indicate that future climate changes could include: increasing

temperatures with the difference between average day and night time

temperatures decreasing; changes in rainfall patterns, reduction in total

annual rainfall, more intense rainfall events and on average longer dry

periods; and an increase in the average intensity of tropical cyclones.

Broad ranges in parameter values can be used to define current

and future climates across the Caribbean. Yet within this scope

significant uncertainty, exacerbated by phenomena such as El Niño

Southern Oscillation (ENSO), exists. These uncertainties in climate

parameter values from year to year and from season to season can,

and often do, have significant impacts on climate sensitive sectors

in the Caribbean.

Climate sensitive sectors

The performance of such sectors as tourism, agriculture, energy, water,

health, insurance and financial services, recreation, and sport is critical to

the socioeconomic development of the Caribbean, but these sectors also

happen to be particularly sensitive to climate. Their ability to generate

profits and provide services in an efficient and effective manner relies in

part on timely and accurate climatic forecasts that allow them to adapt

their operations over short and long timescales.

Although agricultural productivity is decreasing across many

Caribbean states, agriculture still represents a significant foreign

exchange earner and in many rural communities it is still the primary

source of employment and income. Climate dictates the type of agri-

culture practiced as it influences such factors as water availability

(for both rain and irrigation-based agriculture), soil moisture condi-

tions, and rain-fed growing seasons. Because of this, not only is a

historical understanding of climate important for agriculture, but so

too are climate forecasts which can be used to support on-farm deci-

sion making (such as type of crop to be sown, irrigation scheduling

and harvest times) to maximize productivity and revenue. Climatic

information, for example, is particularly important for determining

the timing of interventions such as the application of pesticides and

fertilizers where significant expenditure and environmental degra-

dation may occur from poorly planned applications. However, the

application of climate products to inform farming activities is not as

widespread as it should be in the Caribbean, instead climate indicators

based on traditional knowledge are still commonly used to inform

farming in rural communities. Although the use of traditional knowl-

edge is acceptable under some circumstances, the rapid changes in

climate currently observed and predicted may marginalize the use of

such traditional knowledge which is based on a long history of obser-

vations. The susceptibility of Caribbean agriculture-based economies

to extreme weather and climatic events was demonstrated during

the floods in Guyana from December 2004 to February 2005, which

accounted for USD55 million in agricultural losses and in Grenada,