This report uses the latest geospatial data and satellite telemetry to formulate various sea-level rise scenarios given current climate change predictions. Specifically, the report reveals what the real loss in terms of land area would be at various instances of sea-level rise. It accomplishes this objective with the aid of several up-to-date maps that have had sea-level changes superimposed on them.

The following is a very short except of the full report conducted in 20019.

The full report can be downloaded at: http://eldis.org/go/home&id=60702&type=Document#.U-djdWt5mK0

Moving on five years later I can only wonder at how much of this report has found its way into our designs, planning laws, budgets, and whether there is a copy of it in every one of our Members of the Legislative Assembly’s hands and/or they have even read it?

Reading it has made me feel very uncomfortable indeed. Also check out the second report with link at the bottom of this story. You may not ever sleep again!

All IMAGES are taken from the Cayman Islands Report.

SEA LEVEL RISE AND ITS IMPACT ON THE CAYMAN ISLANDS

Produced by The Cayman Institute for the Government of the Cayman Islands and the British Foreign and Commonwealth Office

Authors: Dr. Murray C. Simpson, Nicholas B. Robson and Professor David Smith

MAY 2009

A report on secondary research undertaken with both a national and international perspective into sea level changes in the Cayman Islands.

EXECUTIVE SUMMARY

The Cayman Islands are particularly vulnerable to the effects of global climate change on the surrounding sea surface. The islands do not appear to be subject to significant land movement, and sea surface levels around the islands are close to the global mean according to satellite telemetry, consequently forecast changes in mean global sea surface levels are likely to be realistic for the Cayman islands. The total mean global sea surface rise by 2100 estimated by the Intergovernmental Panel on Climate Change Fourth Assessment at between 0.18 and 0.59 metres is likely to be exceeded according to recent research, reaching at least 1 metre. The rate of sea surface rise, presently circa 3.1mm/year, may have increased at least threefold by

2100. These changes will result in beach erosion and the widespread destruction of mangroves, thus rendering the coastline even more vulnerable to flooding than at present.

Forecast changes in the intensity and longevity of hurricanes and tropical storms will exacerbate the effects of sea surface rise. Associated storm surges may increase in magnitude, increasing beach erosion and in particular the erosion of coral reefs. Given the observed effects of coral bleaching probably related to periods when sea temperatures are higher than the mean, reefs may be particularly affected. The combination of rises in the sea surface and increases in the intensity and longevity of storms can only result in serious coastal erosion and flooding. Tsunamis will undoubtedly occur some time in the future, and higher sea surface levels will increase their impact, but their size and frequency cannot be forecast.

Adaptation to these changes will be assisted by improvements in knowledge. There is an urgent need for more detailed information on the progress of relative sea level change. This should be provided by both ground and satellite measurement of sea levels and land movement. There is also an urgent need to determine whether or not the frequency of hurricanes and tropical storms is increasing and on what timescales. A detailed and systematic survey of the health of all coral reef areas around the islands is needed to identify trends and locate reefs that are at risk. The response of mangroves in the Cayman Islands to rates of relative sea level rise and likely future rates needs determination. With improved knowledge of the threats to the coastline, adaptation can be planned. A sustainable approach to coastal defence is probably the most effective in the long run, with planting of trees and shrubs that will trap sediment and disrupt waves. Revised planning laws for coastal development may be needed, and both water supply and sewage arrangements may need to be examined. Some changes in the pattern of tourist activity will be required.

Notwithstanding the many problems which climate change will bring to the Cayman Islands, there are opportunities. The response of the islands may provide an exemplar for similar but more vulnerable or less developed small islands elsewhere in the world. The future may be gloomy, but there is much that can be done.

3. Situational Analysis Summary

The Cayman Islands are today at an important juncture in their development history. The population has been growing at 4.73% per year. As an indication the islands population grew 428% between 1970 and 2006. If this trend continues the projected population will be

134,000 by 2026.[1] As well, the construction industry is booming with new condominiums, homes and apartments being built and rumours of new hotels flourishing. In light of the projected population growth and construction boom, now may be the time to consider some of the effects that climate change may have on these islands.

The Cayman Islands, being low lying islands with an average height above sea level of seven feet are vulnerable to rising sea levels caused by global warming. Without resolute counteraction, climate change will overstretch many societies’ adaptive capacities within the coming decades. [2] As has been stated by the World Bank, the Intergovernmental Panel on Climate Change [3] and NASA’s Goddard Institute of Space Studies [4] sea levels are rising due to manmade Green House Gas (GHG) emissions’. During hurricane Ivan in September 2007 over 70+% of Grand Cayman flooded to depths varying from a few inches to 10’+ feet.

Many of the islands homes, resort hotels and condominium developments are built on the coastline and are extremely vulnerable to adverse weather and the resulting storm surge. Storm surge and wave damage will be compounded by sea level rise in years to come, making it imperative that the issue be addressed today. The two oil companies represented in the Cayman Islands, Exxon and Chevron have their oil storage installations on the Western coast of the islands, making them vulnerable to storm surge / wave action from the west, the fact that these installations are situated among residential areas makes the danger greater. Grand Cayman’s only airport, Owen Roberts International is also on the coastal flood plain, bordering as it does on the edge of the North Sound. This vital part of the countries infrastructure was flooded in hurricane Ivan. During the same incident the islands communications infrastructure was rendered unusable, due either to loss of electrical power or wind damage to masts and antennas. Caribbean Utilities, Grand Cayman’s only supplier of electricity is situated on the shores of the North Sound and within the coastal flood plain. During a severe storm or hurricane the generators are shut down as there is a strong possibility that segments of the transmission and distribution grid will be destroyed and that the plant itself will be flooded. Much of Grand Cayman’s potable water infrastructure was destroyed in hurricane Ivan as the mains supply follows, to a large degree, the coastal roads making it vulnerable to damage from wave action and storm surge.

Sea level rise (SLR) due to climate change is a serious global threat: The scientific evidence is now overwhelming. Continued growth of greenhouse gas emissions and associated global warming could well promote SLR of 1m-3m in this century, and unexpectedly rapid breakup of the Greenland and West Antarctic Ice Sheets (WAIS)[5] might produce a 5m SLR. [6] NASA’s James Hansen and his collaborators argue that based on the paleoclimate records is that sea level rise is likely to be five metres this century under a business as usual (BAU) trajectory. [7]. In December 2006, data presented to the American Geophysical Union Conference suggested that the Arctic might be free of all summer ice as early as 2030 and likely by 2040. This will have the effect of setting up a “positive feedback loop” with dramatic consequences for the entire Arctic region. The question in relation to Greenland is whether or not the ice cap can survive the forcing contributed by the albedo effect of open ocean for the duration of Arctic summers.

Dr. James Hansen states that there has been and still is a reticence within the scientific community to state one’s personal views on controversial subjects, of which rising sea levels is certainly a controversial one. He further states “as a physicist, I find it almost inconceivable that [under a] Business as Usual (BAU [scenario]) climate change would not yield a sea level change of the order of meters on the century timescale“. This in comparison to the Intergovernmental Panel on Climate Change (IPCC) whose midrange projection for sea level rise this century is 8–17 inches and full range is 7–23 inches. [8] The IPCC report goes on to note that they are unable to evaluate possible dynamical responses of the ice sheets, and thus do not include any possible ‘rapid dynamical changes in ice flow. [9] Other scientists have noted that if one uses the observed changes of the past century that we end up with a projection for the next century of over one meter. [4]

Rising sea levels have three causes, the first being the expansion of the planet’s oceans caused by the rising temperature [3], and the second being the melting of ice caps and glaciers globally and the third is the change in terrestrial storage. The IPCC “Climate Change 2007 Report [8] Fourth Assessment Report states that ‘Warming of the climate system is unequivocal, as is now evident from observations of increases in global average air and ocean temperatures, widespread melting of snow and ice, and rising global average sea level’. [3] In a high level meeting with a senior advisor the British Government the author was informed that the UK is expected to have monsoon type rains in years to come, necessating the replacement of storm drainage systems in many metropolitan areas. [10] This therefore is another consideration for the Cayman Inlands, that due to the rising average global air temperature, the atmosphere will be able to hold more moisture leading to heavier rainfall and inevitably greater terrestrial flooding, [11] [10] flooding that is already problematic and will be exacerbated by increased sea level.

The World Bank states that to date there is no evidence that the international community has seriously considered the implications for sea level rise for populations in high-risk areas. [6] The OECD has published a report in conjunction with Risk Management Solutions [12] (RMS) and the University of Southampton looking at the effect on the worlds major sea ports, however little has been published with reference to the effect on vulnerable populations. Nor has there been any evidence of the Cayman Islands considering the implications of these phenomena. During Hurricane Ivan, seventy percent of Grand Cayman flooded as shown on the map prepared by the Cayman Islands Lands & Survey Department

Given the magnitude of the problem facing the Cayman Islands, and indeed all Small Islands Developing States (SIDS), not to mention many of the worlds major sea ports [13] [14] including those in Florida, from which the Cayman Islands get their supplies, we should start to address the issue today. At the present time the Cayman Islands Government (CIG) are discussing the construction of new cruise ship and cargo docking facilities and therefore consideration has to be given, not only to future sea level but beyond this to the effect of hurricane storm surge on top of the increased average sea level. The Owen Roberts International airport was out of operation in the immediate aftermath of hurricane Ivan due to flooding and now a new terminal is being constructed.

Rising sea level will impinge on many aspects of life in the Cayman Islands; it will affect construction of infrastructure such as roads, aircraft runways, port infrastructure, on fresh water lenses, on agriculture, on sewage and refuse disposal and on disaster management. The risk to the population will be heightened and the availability of insurance and mortgages may become problematic. At present, there are areas of the Island of Grand Bahama Island in the Bahamas where the residents cannot obtain insurance on their homes because of past flooding. [12] In the risk management industry the Cayman Islands are in the most severe category of risk due to their geographic location. [12] Planning regulations will have to be adapted to make allowances for all of the above scenarios as will all utility planning by Cable & Wireless, Caribbean Utilities Company Ltd., the Water Authority and Cayman Water Company. Hurricane shelters will have to be increased, both in numbers to shelter the growing population and in elevation to protect against higher storm surge.

Many countries have implemented sea defences, such as the Thames Barrier or the North Sea defences on the coast of the Netherlands. The Netherlands is coming to grips with rising sea level by examining the feasibility of constructing offshore barrier islands for coastal protection, [15] which may also be used for siting wind turbines. They are also giving consideration to declaring certain areas as no-build areas so that they may be utilised as flood plains. However, the viability of sea defences for an entire island may well be cost prohibitive. In the short term the answer may lie in enhanced regulations and policy by the Government of the Cayman Islands to ensure that all future buildings and infrastructure are constructed at sufficient elevation above sea level to minimise potential damage by storm surge. All critical utilities would have to be protected against potential damage and their transmission infrastructure would have to hardened or elevated.

8. Adaptation

There is little doubt that the observed rise in relative sea levels globally, the increase in hurricane intensity and longevity, and the prospect of tsunamis place the Cayman Islands at great risk in the near future. This prospect requires adaptation, and actions undertaken thus far demonstrate that the island community is aware of the need for this. Hurricanes can cause enormous loss of life and damage to infrastructure (Pielke et al., 2003; Cayman Islands Government Report, 2006), as inhabitants of the Cayman Islands know well. Tompkins (2005) has described the approach of the Cayman Islands Government to hurricane preparedness, in which the importance of greater institutional integration is emphasised and improved planning legislation introduced. The annual National Hurricane Plan, produced since 1989, has been formalised into government planning processes and Tompkins observes that the ability of the government to respond to hurricanes is now greatly improved. Bueno et al. (2008) have quantified the costs of not responding to climate change, and in the case of the Cayman Islands, they estimate that this will rise to 8.8% of GDP in 2025, and to 53.4% in 2100 based upon the Intergovernmental Panel on Climate Change 2007 report. Given that sea levels will probably rise by a greater amount than IPCC estimated, the figures provided by Bueno et al. (ibid.) must be regarded as at least very conservative.

More broadly, government institutions in the Caribbean remain responsive to environmental hazards. Conferences and workshops are regularly held on the subject across the Caribbean. For example, the Cayman Islands Government Department of the Environment, the UK Tyndall Centre for Climate Change Research and the Caribbean Community Climate Change Centre (CCCCC) organised a workshop on “Preparing and adapting to climate change in the Caribbean” in 2005 (Tyndall Centre, 2005). Several organisations have been established to undertake research on climate change in the Caribbean. Thus, the Mainstreaming Adaptation to Climate Change (MACC) project (Caribbean Community (CARICOM) Secretariat, 2009) aims to mainstream climate change adaptation strategies into the sustainable development agendas of small island and low-lying states. The Caribbean Planning for Adaptation to Climate Change (CPACC) project (CARICOM Secretariat, 2009) seeks to build capacity for the Caribbean region to adapt to climate change impacts, particularly sea level rise through in particular the establishment of a sea level/climate monitoring network and the establishment of databases and information systems (UNESCO,

2003).

The Caribbean Community Climate Change Centre (CCCCC) (Heads of Government of the Caribbean Community, 2004; CARICOM Secretariat, 2009) was established in Belize in 2004 with a mandate to coordinate the regional response under the management of the Caricom Council for Trade and Economic Development (COTED) (Second UK/Caribbean Business Forum, 2007). CCCCC has links with scientists and organisations overseas involved with the study of climate change, including the Hadley Centre, the Tyndall Centre and the UK Climate Impacts Programme. Projects involving climate modelling, studies of the impact of rising sea levels, and the effects of hurricanes on coral reefs are being undertaken. CCCCC began a UK Department for International development (DFID)-funded project on enhancing the capacity for adaptation to climate change in the Caribbean Overseas Territories, in 2007, and the project is scheduled to run until 2010 (DFID Research and Development Report, 2007). Sea level rise is a major component of the project. Studies such as those of the Tyndall Centre (e.g. Gill et al., 2004) are examining the impact of environmental and economic impacts. The Adaptation to Climate Change in the Caribbean (ACCC) Project was designed to sustain activities under CPACC and address issues of adaptation and capacity building not undertaken by CPACC. It was succeeded by CPACC. The United Nations Environment Programme in collaboration with the Caribbean Community and Common Market CARICOM has produced several documents on the Caribbean environment, and notably on the challenge of adaptation. The matter of adapting to climate change was an issue at the 53rd Commonwealth Parliamentary Conference in India in 2007.

The many organisations, reports and meetings listed above demonstrate an awareness of the problem posed by global environmental change, but most were organised, produced or took place before the Intergovernmental Panel on Climate Change Fourth Assessment Report in the autumn of 2007. In that report, the challenges of adaptation were addressed in Chapter 16. Several key areas were identified as being underrepresented in contemporary research on the impacts of climate change on small islands. Of particular relevance to the Cayman Islands these included the role of ecosystems, such as mangroves, coral reefs and beaches in providing natural defences against sea level rise and storms; the development of appropriate methods and tools for identifying critical thresholds for biogeographical systems; and the strengthening of local capacity in areas of environmental assessment and management. These and other issues have been made more urgent in the light of the recent information on the likely acceleration in global sea surface rise. Adaptation strategies will need to be revised as the impacts of increased sea surface rise are assessed.

The review of the literature on relative sea level rise and extreme flooding events undertaken here has identified a number of actions which need to be taken if the effects of climate change in this field are to be mitigated. These are as follows:

.1 Estimating the pattern and rate of relative sea level rise. Relative sea level change at the coast is a consequence of both sea surface change offshore and land uplift onshore. In so far as sea surface change is concerned, global sea levels do not rise at the same rate and by the same amount everywhere. As the rising sea surface encounters coasts of varying bathymetry around the world the rise will vary. As great ice shelves disintegrate, their gravitational attraction is reduced and the sea surface level drops in their vicinity but rises elsewhere. Even over timescales of decades the sea surface rise will vary. In this context, the several graphs of sea surface rise in the Caribbean are only generalisations, and conceal fluctuations by the nature of the methodology employed. The changes in the future may decelerate at times, but may also accelerate. Where land movement is concerned only the most general information is available. For the Cayman Islands it is imperative that accurate measures, from both tide gauges and satellite telemetry, are obtained to track the rising sea surface and the changing land level. Knowledge of the rate of rise is important if the actual amount of coastal change is to be forecast.

.2 Determining changes in the activity of hurricanes and tropical storms. Further information on the relationship of hurricanes and tropical storms to ENSO is needed and more accurate forecasts of track, intensity and longevity are needed. In particular, however, the issue of frequency needs to be urgently addressed. The literature demonstrates differing views on this, with the balance being that frequency is not increasing overall, but is fluctuating, but given the Cayman Islands’ record of hurricanes, this needs to be urgently determined.

.3 Determining the impact of relative sea level changes and hurricane activity on coral reefs. Coral reefs are the first line of defence along the Cayman Islands coastline. Any deterioration in the reefs will render the land behind more vulnerable to erosion (e.g. Watkinson, 2003). Coral bleaching is of concern, since it leads to break up of reefs. The bleaching event of 2005 was particularly serious (e.g. NOAA). Hurricane activity may lead to the irretrievable decline in reefs (e.g. Gardner et al., 2003; 2005). Hence, detailed monitoring of reefs spatially must be undertaken if future changes in the coastline are to be detected. The response of reefs to the changing rate of relative sea level rise needs to be closely monitored. If rises of as much as 15mm/year occur, can reefs respond? It seems unlikely, but there may be feedbacks, for example in the reduction of reef exposure to storm surges as the sea surface level rises.

.4 Determining the impact of relative sea level changes and hurricane activity on mangroves. It is understood that in some areas of the islands, mangroves are protected by ridges of coral eroded during storms. However, forecast rates of relative sea level rise and of more intense hurricane activity would seem to be inimical to the survival of many mangrove areas. Since mangroves protect the coast in some areas, this will be of concern.

.5 Protecting the coast   from   the impacts of relative sea level changes and extreme floods. Conventional protective measures are unlikely to be realistic, but a particularly useful measure would be the further establishment of woodland in coastal areas. In areas where tsunamis are more prevalent than in the Caribbean, planting palms is very effective. Palms will survive the greatest tsunami known, and if the forest is sufficiently dense, will act as traps for sediment. Their response to storm surges has not been studied as far as the writer is aware, but they may well prove a useful defence. Mangroves are also valuable in protecting the coast, but may not survive forecast rates of sea level rise.

.6 Developing further effective planning measures. Taking a cue from studies in tsunami-prone areas, planning measures such as when building larger structures like hotels and apartment buildings a skeletal ground floor plan and spaces between large sea front properties may be of value in the event of storm surges. Studies in Greece have identified these and other measures (e.g. Papathoma et al., 2003) as being effective in flooding events. Drinking water supplies are met by desalination plants and rainwater catchments, so saline penetration of the groundwater reservoir is not an issue. However, as relative sea levels rise and hurricane activity intensifies the location of storage areas for drinking water may have to be reviewed as may the sites for sewage disposal, including septic tanks and deep well injection sites.

.7 Responding to the challenges faced by the tourism industry. The impact of sea level rise and increased hurricane intensity and longevity on tourism in the Cayman Islands will be largely negative, and present a challenge to the tourism industry, an observation echoed by the Fourth Assessment Report of the Intergovernmental Panel on Climate Change. To offset this negative effect, attraction of increased cruise traffic may be one approach, but ultimately as income from tourism reduces, alternative sources of income and employment will have to be sought.

The Cayman Islands are a strong contender for a global sea surface monitoring location. There is probably no other location in the Caribbean area where the land could be sufficiently stable such that records of relative sea level are close to the mean for the globe. Isostatic effects are unlikely to be significant, given that the seabed slopes so steeply on three sides. Tectonic effects are small, according to available evidence. The sea surface altitude is close to the global mean and is unlikely to change in the foreseeable future. Hence the islands could serve as a laboratory for future studies of the progress of global warming. Perhaps an outrageous suggestion, especially since this report is only based on secondary research, but probably one worth examining.

9. Conclusion

The marine environment of the Cayman Islands is one of low tidal range but noticeable wave and current activity. Sea levels around the islands have been rising for several thousand years and the coastline has been retreating, most notably in mangrove areas, but until recent decades coastal retreat in the islands has probably not been a major concern.Carol Ann holiday snaps

This secondary research study recognises that in recent years, global warming has begun to change the picture. Although the effect of tectonic activity is unknown, it seems reasonable to assume that the rate of rise in sea levels around the islands is currently about 3mm/year and will probably increase in the future as the Greenland and Antarctic ice sheets deliver increased volume to the oceans and seas of the world. Since the islands are subject to hurricane activity, and since this may become more intense as sea surfaces become warmer, the combination of a rising sea level with storm surges that could exceed 6m in the strongest hurricanes, poses a considerable threat to the islands. In addition, tsunamis are not unknown in the general area, and with the increased rise in relative sea level are of concern, although not as immediate as hurricane activity. Given the low elevation of the islands, the likely effects of sea level rise on the population and infrastructure must be of concern.

In view of the threat posed by rising sea levels, more intense hurricanes, and possible tsunami impact, it is evident that responses are needed. The developing policies and actions of the Cayman Islands Government demonstrate an awareness of this, and indeed, the Cayman Islands are probably better placed than many small island communities to respond to climate change. As such, it is conceivable that the Cayman Islands may take a lead in the response of the small island community worldwide. However, the need for response has been heightened by the recently identified probability that the sea surface may rise by a greater amount than forecast by the Intergovernmental Panel on Climate Change Fourth Assessment Report. It is argued that there is a more urgent need for effective adaptation than may be currently appreciated.

END

 

Also see another important report on climate change and rising sea levels that features Jamaica:

Adaptation to climate change and managing disaster risk in the Caribbean and South-East Asia

This report is an of the outcome of the Seminar on Climate Change and Severe Weather Events in the Caribbean and Asia, held in Barbados in July of 2003. Presentations made at the seminar were based on six case studies carried out in the Caribbean and Southeast Asia. In the tourism sector, studies were conducted in the Bahamas and Thailand; studies on agriculture and fisheries were carried out in East Timor and Belize, respectively; and the urban water case studies were undertaken in Jamaica and the Philippines.

The full report can be downloaded at: http://www.riesgoycambioclimatico.org/biblioteca/archivos/DC1064.pdf