Regional Impacts - South Pacific
There is one UKOT in this region: The Pitcairn
- Annual and seasonal ocean surface and air temperature
increased by 0.6° to 1°C since 1910 in much of the Pacific.
- There has been a significant decrease in the annual number of
cool days and cool nights, particularly after El Niño events, for
the period 1961 to 2003.
- Sea level rise has varied across the region, ranging from 1.5
mm to more than 3mm per year.
- Tropical storm intensity has increased and a relationship
between ENSO and the tracks, density and occurrence of cyclones has
been observed (Walsh, 2004 cited in Mimura et al.,
The IPCC suggests the climate in the Pacific could be in a
permanent El Niño state with global temperature increases.
A World Bank study of the potential impacts of climate change
scenarios in the Pacific (World Bank, 2000) projects the following
- Sea level may rise 0.5m (“best-guess” scenario) to 1m
- Air temperature could increase between 1.6° and 3.4°C.
- Rainfall could increase or decrease (most models predict an
increase) by 20 per cent, leading to more intense floods or
- Cyclones may become more intense, with wind speeds increasing
by as much as 20 per cent; intensity could increase by 5 to 10 per
cent by 2050 (Walsh, 2004 cited in Mimura et al.,
Implications and possible future impacts
Changes in rainfall will also affect agricultural production.
Loss of coastal land would reduce the available space for
cultivation in some countries. In low-lying ones, salt-water
intrusion would also affect production of copra, breadfruit and
panadanus. A decline in the cultivation of some traditional crops,
such as yams and taro, would also affect the subsistence economy of
the Pacific islands (World Bank, 2000).
The tuna fisheries in the western and central Pacific could
Diarrhoeal and vector borne diseases are expected to increase
with warmer temperatures in the Pacific. As in the Caribbean, the
frequency, severity and distribution of dengue fever could
increase, as warmer temperatures reduce the incubation period of
the dengue virus and speed up the larval stage of the
Climate change could also increase the incidence of ciguatera
poisoning. Habitat disturbance, including from extreme weather, and
warmer waters cause the algal blooms that produce the ciguatoxins,
which are ingested by fish. In Kiribati, which has one of the
highest rates of ciguatera poisoning, for example, by 2050
the incidence of poising is expected to go up from 35 to 70 people
to 160 to 430 per thousand (World Bank, 2000).
Variations in rainfall will affect water supplies in some
Pacific islands. Ground water supplies in low-lying islands could
be affected by salt-water intrusion.
Coral reefs are also likely to be affected by bleaching events,
which could lead to death of the corals and a decline in fisheries
and a long-term reduction in coastal protection. Mangroves are
likely to be affected by sea level rise and flooding and inundation
will affect the costal zone in some islands.