Tropical storm surges and waves can overwhelm island communities, as occurred at Manihiki (Fig. 5a), northern Cook Islands, during passage of Cyclone Martin in November 1997—only four houses were left standing in the two island villages and 20 residents were lost (de Scally 2008).
Maragos et al. (1973) provide a graphic description of flooding and wave overtopping on Funafuti Atoll, Tuvalu, during Cyclone Bebe in October 1972. Forbes (1996) and Solomon and Forbes (1999) described storm impacts from Cyclone Ofa in 1990 on the raised island of Niue (Fig. 7). Numerous facilities on top of coastal Selleckchem JNK-IN-8 cliffs up to 25 m high were damaged severely by storm waves breaking against the cliffs. Many of these facilities were repaired, only to be damaged even more severely by category 5 Cyclone Heta 14 years later. Thus, while raised atolls are largely immune to storm flooding, their eFT508 manufacturer narrow reef fringe, allowing deep-water waves to break almost directly against the cliffs, exposes cliff-top infrastructure and properties to extraordinary wave impact. Sea-level rise and variability Atolls and the low-lying terraces of high islands are susceptible to more frequent or higher flooding under climate-induced acceleration CH5424802 in vivo of global mean SLR. Deepening of water over reefs may increase wave energy at the shoreline and salt water may intrude into island soils and aquifers.
Sea-level variability due to ENSO or other large-scale circulation, as well as tides and storm surges, all ride on the MSL. Thus it is important
to develop robust projections of local SLR for individual regions and islands. These require knowledge of the global drivers as well as local factors such as uplift or subsidence rates. There is a growing consensus that the SLR projections of the IPCC (2007) AR4 were conservative and that SLR this century is likely to exceed AR4 estimates (Rahmstorf et al. 2007; Rahmstorf 2010; Church and White 2011). Post-AR4 projections of twenty-first century global mean SLR range up to 1.4 m or more but less than 2 m (Rahmstorf 2007, 2010; Pfeffer et al. 2008; Grinsted et Cytidine deaminase al. 2009; Jevrejeva et al. 2010, 2012; Rahmstorf et al. 2012b). Church et al. (2004, 2008), Church and White (2006, 2011), Domingues et al. (2008), Jevrejeva et al. (2008), Cazenave and Llovel (2010) and others have documented the slow rise of GMSL since the nineteenth century, slow or intermittent acceleration through the twentieth century, and more rapid acceleration over the past two decades. Meanwhile, satellite altimetry over the ocean basins since 1993 has revolutionized the monitoring of GMSL (Leuliette et al. 2004), showing an upward trend well correlated with the tide-gauge reconstruction that suggests an acceleration to 3.2 ± 0.4 mm year−1 (1993–2009) from the mean rate of 1.9 ± 0.4 mm year−1 since 1961 (Church and White 2011).