Turks and Caicos Islands

3). Factors which increase the vulnerability of aquifers to saline intrusion include (i) their proximity to the
sea, (ii) increasing abstractions due to rising demand from domestic, agricultural and industrial uses
(Karanjac, 2004), and (iii) declining groundwater recharge through reduced precipitation or an increased
proportion of surface runoff through precipitation occurring in higher-intensity, shorter-duration events
(Bates et al., 2008) or decreased infiltration of water through land-cover changes agriculture (Scanlon et al.,
2005; Zhang and Schilling, 2006). In the Turks and Caicos Islands, it is expected that among the damages
that sea level rise may cause are the loss of agricultural land and coastal fresh water resources through
erosion, and salt water intrusion into aquifers (Climate Change Committee, 2011). Sea level rise may also
result in damage to infrastructure associated with desalination infrastructure (Byron, 2011).
Agriculture and irrigation
Globally, agricultural water use comprises around 70% of total water extractions (Wisser et al., 2008) yet, in
the drier, warmer environment expected under climate change in the Caribbean, irrigation water demand
is likely to increase, exacerbating the effects of decreases in water availability (Döll, 2002). Increased
evaporative demands under climate change may lead to reductions in irrigation efficiency (Fischer et al.,
2007). Careful consideration will need to be given to efficient irrigation practices and technology to reduce
wastage and increase the amount of water reaching the crop, estimated to be as low as 40% worldwide
(Pimentel et al., 1997).
In the Turks and Caicos Islands, the limited rainfall plus poor quality soil and a limestone base restrict the
possibilities for agricultural development and, as a result of this and a well-organized transportation
system, most food is imported, except for fish, conch and lobster (Kairi Consultants Limited, 2000a).
Greater agricultural potential exists towards the north west of the group, including North Caicos and
Providenciales, due to the relatively higher rainfall received, although the agricultural potential of North
Caicos remains largely unexploited (Kairi Consultants Limited, 2000a). However, declines in agricultural
production are expected throughout the Turks and Caicos, due a lack of water supply for irrigation (Climate
Change Committee, 2011). In addition, the Climate Change Committee (Climate Change Committee, 2011)
has noted that “rising sea levels could lead to loss of land for agriculture due to salinization and
inundation”.
Flooding
Intense rainfall from storm events may only last a few hours, but can result in serious rapid-onset flooding,
particularly when they occur in catchments that are small, steep or highly urbanised, as is the case in the
much of the Caribbean region. Floods are a particular problem for water resources because, aside from the
potential for loss of life and property, they can affect water quality and have implications for sanitation and
cause serious soil erosion. Flooding erodes topsoil along with animal waste, faeces, pesticides, fertilizers,
sewage and garbage, which may then contaminate groundwater sources as well as marine areas. Erosion
may lead to the formation and deepening of gullies which, if they develop in hillslope areas with temporary
water tables, may lead to enhanced drainage leading to groundwater discharge (Poesen, 2003).
While GCM modelling projections indicate an overall tendency for decreases in overall precipitation across
the Caribbean region (see Section 3), excluded from these projections is the potential of an increase in the
frequency and intensity of storm events with associated heavy rainfall (Frei et al., 1998; Min et al., 2011),
including those associated with hurricanes. Research by Emanuel (2005) shows a strong correlation
between hurricane size and sea surface temperature, suggesting an upward trend in hurricane destructive
potential. Statistical analysis (Trenberth, 2005) and modelling (Knutson and Tuleya, 2004) suggest that
hurricane intensity will increase, with the north Atlantic Ocean in particular showing an increasing trend in
storm frequency (Deo et al., 2011).
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