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Climate Change
Impacts Have Been Underestimated,
Briefing paper
for delegates to the framework convention on climate change negotiations. Thomas J. Goreau, Ph.D. NOTE: This paper, written to brief delegates to the Framework Convention on Climate Change, outlines the reasons why the Convention, as it now stands, is incapable of protecting coral reefs from climate change, and makes specific suggestions for changes which would allow the Convention to meet its own goal of avoiding dangerous interference with the Earth's climate system. More detailed references on all the points made in this paper are given in the other papers on the Global Coral Reef Alliance web site. SUMMARY Coral reefs worldwide have shown clear signs of severe stress due to high temperatures over the last 15 years, and will be unable to tolerate a further warming of 1 degree, contradicting the view that possible catastrophic climatic stresses to major ecosystems lie only in the remote future. Strong action to stabilize greenhouse gas concentrations is needed immediately to maintain the economically-crucial shore protection, tourism, fisheries, and biodiversity services provided by coral reefs to over 100 countries. Potential long-term increases of global temperature and sea level due to increased carbon dioxide based on the actual worldwide changes which have occurred over the last 160,000 years are from ten to a thousand times greater than those which are predicted over the next 30 to 50 years in theoretical models used by the Inter-governmental Panel on Climate Change (IPCC). This indicates that too short a time horizon has been used by IPCC, and suggests that the major feedback mechanisms and time lags linking these variables have not been fully included in the models. Despite widespread fears that serious greenhouse gas stabilization is too economically expensive, greenhouse gases can be cheaply stabilized at safe levels by: 1) use of ecological criteria for acceptable rates of climate change; 2) full accounting of all greenhouse gas sources and sinks; 3) reforestation of degraded lands on a scale adequate to absorb excess carbon dioxide production; 4) investment in large-scale manufacture of photovoltaic panels to make solar-generated electricity cost-competitive with fossil fuels; 5) use of mineral accretion technology to protect shorelines from erosion; and 6) improvements in energy efficiency. A. THE PROBLEMS: The extreme vulnerability of corals to high temperature make coral reefs the most sensitive ecosystem of all to global warming. They are so close to their upper temperature limits that they will not be able to survive a further global warming of 1 degree C. To prevent destruction of critical services of fisheries. shore protection, tourism, sand production. and biodiversity (which make coral reefs the most valuable ecosystems in over 100 countries). global climate change must be held down to levels within the tolerance of corals. If the world community fails to do so, corals will die sooner or later causing severe damage to the economies of all coral reef countries. and the actual disappearance of the lowest lying countries like the Maldives, Kiribati. Tuvalu. Tokelau. and the Marshall Islands. Honest assessment of climate change must deal with the full magnitude and time scale of the changes which will result. not just an arbitrarily small portion of them. Considering only short time horizons seriously underestimates the magnitude of the problem our descendants will ultimately face as the consequence of our lack of action now. 1. The urgency of immediate action on climate to save coral reefs Starting in the early 1980s, many coral reefs around the world began "bleaching". This extreme stress response causes the tissues of the coral to lose their color, resulting in starvation, failure to grow or reproduce, and to death of the coral if sufficiently severe. This phenomenon, unprecedented on a large scale, was at first mysterious and its causes controversial, but it has since been clearly shown to be due to high ocean temperatures. What was surprising was the small temperature increase which triggered bleaching, only one degree C above normal in the warmest month. This threshold has now been found to apply to reefs worldwide, and is identical to heat thresholds measured in laboratory experiments. It appears that the increase in global temperatures which took place at the very end of the 1970s began to push corals over this threshold for the first time. Coral banding growth records (similar to tree rings) before the 1980s are complete and show no signs of years without growth which would be caused by bleaching events. Corals growing in waters which were warmed by one degree or more by hot water from power plants or desalinization plants bleached and died. There has been no sign of coral recovery, acclimatizion, or recolonization of the dead zones since the phenomenon was first described in the 1970s. This indicates that corals are unable to adapt to these elevated temperatures, and that they had never previously experienced them on a large scale. By 1990 our detailed analysis of worldwide satellite sea surface temperature data had indicated that every major mass bleaching event followed periods of only around one degree C warmer than average in the hottest months, and since then we have been able to predict every major bleaching event in real time from satellite data alone. This includes bleaching of reefs in French Polynesia and Samoa in 1991 and 1994, the Cook Islands, Niue, and East Africa in 1994, Okinawa and Bermuda in 1991, the Caribbean in 1991, 1995, and 1997, Brazil in 1995 and 1996, New Caledonia, the Red Sea, Persian Gulf, and Hawaii in 1996, and the Maldives, Sri Lanka, and the Eastern and Central Pacific in 1997. Coral bleaching has taken place almost every year and in almost every reef region of the world, with the only exception being during the two years after the eruption of the Pinatubo volcano in the Philippines, which put so much fine aerosol haze into the upper atmosphere that sunlight was reflected back into space and the entire earth cooled until it settled out. The temporary relief from bleaching indicated that pollution or other man-made stresses are not responsible for bleaching. Unfortunately however, the hypothesis that pollution rather than temperature was the cause of bleaching was proposed by politically motivated individuals in the late 1980s without data to back it, and the unwarranted publicity they were given continues to confuse the public as to the real causes of bleaching. As a result, the repeated worldwide bleaching events caused by hot temperatures which have taken place repeatedly since then have not been covered by the press or come to the attention of negotiators concerned with global climate change. Unfortunately the large body of research which has documented these bleaching events and their link to excessively high temperatures, much of which has been published, has been overlooked in IPCC assessments of climatic vulnerability of ecosystems. Bleaching is mentioned only once in the latest IPCC assessment of vulnerability of small island states, more as a theoretical possibility rather than as a spreading and intensifying reality, and the only citation given is one of this author's papers on long term changes in Jamaican coral reefs from 1951 to 1991. That paper discusses the lack of correlation of recent bleaching to any known stress other than temperature but deals only with the situation in Jamaica. The papers since published assessing global patterns of bleaching and temperature excesses are not cited, even though these are the most relevant to assessing worldwide vulnerability of coral reefs to existing temperature variability, even without further warming. Unfortunately the world community has thus far failed to recognize the unique vulnerability of coral reef ecosystems. If global warming causes the elimination of ecosystems in colder climates, these will eventually be replaced by organisms migrating from warmer climates, but if the warmest ecosystems die, there can be no source of immigrating organisms already adapted to the new, even hotter conditions. Such adaptation requires the evolution of new species, which may take millions of years. While corals did live in the warmer oceans which were found worldwide millions of years ago, the hot water adapted corals underwent catastrophic extinctions at the start of the ice ages around 2 million years ago, leaving behind only the relatively cold water adapted corals behind as survivors, the ancestors of the corals found today. These have apparently lost the ability to adapt to the high temperatures which their long extinct ancestors once tolerated. We have recently analyzed detailed satellite sea surface temperature data for every major coral reef region in the world, and the results show several unexpected regional patterns in warming, with strong implications for the vulnerability of coral reefs to bleaching. The greatest rates of warming, much higher than the global average, are found in the northern hemisphere, especially in the Caribbean, the Red Sea, and the Persian Gulf. These are nearly-enclosed seas with restricted circulation, which are warming much more rapidly than the global average because the circulation of surface waters across them appears to be slowing down. In contrast, some reef areas in the southern hemisphere actually show a cooling trend. This pattern can only be explained by increases in the rate at which upwelling of cold deep ocean water is taking place, especially in the Southeastern Pacific. The regional trends which we have found in the satellite data over the past decade strongly agree with patterns found in analysis of merchant ship temperature measurements over the last century by Mark Cane and colleagues at the Lamont Doherty Geological Observatory. They suggested that increased temperatures in the Western Pacific and cooling in the Southeastern Pacific is driving stronger westerly winds, causing more deep water to be pulled up. Such feedbacks which change ocean circulation patterns are not included in models used to predict global climate change, but clearly they must have profound effects on regional sensitivity of coral reefs to warming. Increased upwelling of cold deep water will also cause surface heat to be transported down into the deep sea more rapidly, which will delay global surface warming but will not change its ultimate magnitude. This delay factor could be ended if surface waters become too warm to sink, a possibility discussed in the next section. 2. Variations in climate change prediction in theoretical models Despite the claim of some critics that the greenhouse effect is an unproven hypothesis, there can be no doubt about the reality of the greenhouse effect, which results from an inexorable physical law. Its physical basis is as solidly established as Newton's law of gravity: increase the concentration of a gas which absorbs heat and the atmosphere will warm up (just as a ball thrown up will always fall down). The only uncertainties are how great will be the magnitudes of temperature and sea level rise resulting from increased absorption of heat by increased greenhouse gas concentrations, and how rapidly their rise will take place. These are difficult to accurately predict because detailed knowledge is needed of rates of heat flow throughout the earth's atmosphere, ocean, and ice caps, the rates of greenhouse gas absorption and release by the oceans and the biosphere by natural processes, and changes in them. These are still inadequately measured at present. IPCC's projections for climate change in the next 30 to 50 years are well known: 1 ) carbon dioxide in the atmosphere is expected to increase by 350 parts per million (ppm), doubling its present concentration, 2) global average temperatures are expected to rise by 1 to 4 degrees celsius (C), 3) global sea level is expected to rise by 10 to 50 centimetres (0.1 - 0.5 metres (M)) These figures have been widely publicized, and are being used as the basis for the climate change negotiations on the grounds that they represent the best available consensus of the entire scientific community. These projections are based on theoretical models which estimate the sensitivity of global changes in temperature, sea level, and greenhouse gases (usually only carbon dioxide) to each other. Before they are uncritically accepted, their variability and their accuracy in describing the actual changes of climate recorded in the past must be assessed. This section discusses the variability between predictions from different models, and the next section compares them to measured data of past climate changes in order to assess their accuracy and see if they agree with the actual changes known to have taken place. Projections of future climate change are based on extremely complex physical models which attempt to describe the rate of heat flow between the atmosphere, the ocean, and the polar ice caps. Although these models require the most powerful computers, they would be impossible to run at all unless they were greatly simplified. Forecasted amounts of climate change vary because the rates of heat flow between the atmosphere, ocean, and ice caps, and the length of time over which heat is redistributed between each component of the climate system varies in each model. While the models all agree on the direction of changes which will take place, they disagree in detail over the rate at which this will happen, and the ultimate amount of change, because of subtle differences in the built-in mathematical assumptions simulating reality. It is impossible to realistically describe the internal flows of heat in the atmosphere and in the ocean in the same model simultaneously because of the tremendous differences in speed and heat content between winds and ocean currents. Consequently the heat flow between ocean and atmosphere must be described by greatly simplified formulas. Changes in ocean currents and circulation are usually neglected in most models because of their tremendous complexity and the impossibility of describing these patterns on existing computers in any reasonable time or cost. The problem with this assumption is that the ocean is capable of storing so much heat that even very small changes in ocean circulation can cause large changes in climate. At present it takes around a thousand years for water in the ocean as a whole to mix, but until the heat warming surface waters is redistributed throughout the entire ocean, the full impact of warming will not be felt at the surface. If the overall rate of ocean mixing were to change there will be profound changes in surface temperatures and in how quickly the full impact will be reached. One pioneering model has examined changes in the average circulation of the entire ocean. The model, run on a supercomputer by Dr. Manabe and colleagues at Princeton University's Geophysical Fluid Dynamics Laboratory, suggests that current rates of climate change will eventually cause the surface ocean to become so warm that it will become impossible for it to sink to form new deep ocean water by cooling in the Arctic and Antarctic. This would shut down overall deep ocean circulation, and heat which would previously have been mixed down into the cold deep sea would now accumulate at the surface, accelerating the rate of global surface warming. Small changes in surface ocean circulation which are not now included in the models would have profound effects on the actual rate of warming at any location. Evidence that marked changes in surface and deep ocean circulation are currently taking place, causing visible biological impacts in coral reefs, is presented in an earlier section. 3. Climate change models versus data Global increases in temperature, sea level, and carbon dioxide have been well documented from direct measurements worldwide during this century. Nevertheless the measurements are still not adequate to estimate long term sensitivity of climate variables to changes in one another because the response times to changes are longer than these records. However, clear and sufficiently long records of global changes in temperature, sea level, and carbon dioxide are preserved in the chemical changes measured in cores taken in polar ice caps and in tropical fossil coral reefs. These are backed up by measurements of temperature variations with depth in deep boreholes, dissolved gases in groundwater, positions of mountain glaciers, changes in vegetation marked by pollen in lake sediments, and tree rings. The best data comes from cores taken from the Antarctic ice cap, which preserve a continuous global record over the last 160,000 years. Here these records are used to determine the average sensitivity of temperature, sea level, and carbon dioxide to each other over this entire period as the best long-term indicators of how climate variables have actually responded to each other in the past, as a guide to what might happen in the future. The observations show that as the earth's climate varied between cold ice ages and warm interglacial periods, carbon dioxide increases of 100 ppm were accompanied by increases of global mean temperature between 5 - 10 C, and global sea level rise of 100 - 150 M. The sensitivities (change of one variable in response to unit changes in another) which climatic variables have actually shown over at least the past 160,000 years (and probably also during the last 2 million years of alternating warm and cold periods) with those resulting from the IPCC model estimates (listed in an earlier section) are contrasted below: 1 ) the sensitivity of temperature to carbon dioxide in the observed record is around 10.7 times greater than that of the IPCC projections,
2) the sensitivity of sea level to temperature in the observed record is around 99.7 times greater than that of the IPCC projections, 3) the sensitivity of sea level to carbon dioxide in the observed record is around 1250 times greater than that of the IPCC projections. These comparisons suggest that the projections which are now being used to assess acceptable rates of climate change appear to greatly underestimate the ultimate extent of potential changes in global climate variables based on those which have actually taken place in the past. One reason for this large discrepancy could be that the models do not include all of the major feedback mechanisms by which changes in one climate variable affect another, such as changes in global ocean circulation and changes in the metabolism of the biosphere. Strong feedback mechanisms must exist in the climate system which greatly amplify small changes in sunlight reaching the earth, because otherwise the earth's climate would not show such large changes between ice age and warm conditions which vary in synchrony with changes in the earth's orbit around the sun, but these feedback mechanisms have not yet been adequately understood, characterized, or included in existing climate models. It is no criticism of the sophistication of the climate models to say that if they oversimplify reality and underestimate the actual past variations we should use actually observed changes rather than theoretical model results as our guide. A major flaw in the model projections is prediction of climate chances over inadequately short time intervals. Changes in greenhouse gases will change the amount of heat in the entire earth system, but the full surface warming will not be felt until the deep sea and ice caps have warmed. It takes around a thousand years for heat to mix throughout the deep ocean and thousands of years for the polar ice caps to flow and melt, and until increased heat has thoroughly mixed to the cold areas, the full effect of warming will not be felt at the earth's surface (if we turn up the thermostat on the ground floor of a house whose attic is freezing cold, we will not feel the full warmth until heat has flowed to and warmed up the coldest part of the house). Unfortunately the projections made by IPCC for changes over only several decades are far too short. IPCC chose short prediction time scales because they felt that policymakers would not deal with the full long term changes taking much longer than the interval over which political leaders are likely to feel accountable by their constituents. The unfortunate result of choosing too short a time scale is to introduce a serious logical fallacy in people's understanding of the magnitude of the changes which we must deal with (analogous to telling someone how far a football will fly one tenth of a second after it has been kicked and treating this distance as if it is how far the ball will really fly). Policymakers have unfortunately tended to misunderstand the IPCC projection as being the total magnitude of the change that they will have to deal with, when it is only the down payment, the first in a series of expenditures that will continue to be made over and over again into the indefinite future. They say "Sea level rise of half a meter? We’ll just spend X billion dollars to build a one meter wall around our country!" without recognizing that this expenditure is not a one time adaptation but a recurring outlay which will have to be repeated by each succeeding generation for thousands of years to come. The amount of carbon dioxide in the atmosphere is already around 30% higher than it was during the last interglacial period 125,000 years ago. At that time temperatures were around 1 degree warmer than today, and sea level stood 6 to 7 meters higher than it is now, leaving a clear notch in cliffs which can be seen at sites around the world. Ultimately today's level of greenhouse gases, even if there is no further increase, should drive sea levels considerably higher. Continued increases in carbon dioxide and other greenhouse gases could become so great as to overwhelm the natural feedback mechanisms which caused the warm-cold ice age oscillations of the last few million years, pushing us into a greenhouse world in which the ice caps melt, producing conditions similar to those which the earth experienced in the past from 10 to 100 million years ago, when temperatures were up to 15 degrees warmer and sea level hundreds of meters higher. Such a super-greenhouse world would take many generations to fully develop, but a guide to possible rates of change could be that which happened during the period of warming which ended the last ice age, when sea level rose over 10 centimeters a year. These conditions would irreversibly change the way of life of most of mankind, with costs inconceivably higher than those policymakers envision by misunderstanding limited time horizon scenarios. B. THE SOLUTIONS: The data on sensitivity of coral reefs to climate change indicates that solving the problem of uncontrolled global climate change is far more urgent than is recognized. The solutions are both technically feasible and far cheaper than the ultimate costs of unrestrained climate change. The loss of many or most coral reefs due to excessive temperature extremes could take place within just a few decades if current trends continue, wiping the most economically valuable marine ecosystems of every tropical coastal country, worth up to tens of millions of dollars per kilometer of coastline per year. It is foolish to think that coral reefs would spread to currently colder climates in response to global warming, because they are also the most sensitive ecosystem to excessive nutrients, sediments, and all other forms of pollution, and inadequate water quality would prevent their spread to the newly warmer shores. Even if pollution in those areas were to be cleaned up so that corals could grow, it would take thousands of years for coral reefs to form. Preventing uncontrolled climate change and reef heat death, rather than hoping for adaptation, is clearly the most economical and wisest choice for the world community to protect its endangered coral reef resources. Below are listed six criteria or suggested programs needed for success in controlling climate change, five of which have not been adequately considered in the ongoing debate on climate change. The sixth, improved efficiency of energy use, is so obvious that it is on everyone's list of adaptive measures, and little need be said about it here. The other five are discussed in more detail. 1 ) Ecological criteria for acceptable rates of climate change The acceptable rates of climate change need to be set at a level low enough to be within the capacity of the most climate-sensitive ecosystems to adapt. Because coral reefs are the only ecosystem known to be already at or just below their upper temperature limit, and incapable of surviving a further 1 degree of warming, this should set the absolute value of further acceptable warming under the Framework Convention on Climate Change. The Convention's stated purpose is to protect critical climatically threatened ecosystems, such as coral reefs. Convention negotiators undermined this purpose by failing to identify the most climatically sensitive ecosystems, failing to require their monitoring for signs of climate-induced damage, and failing to require a trigger mechanism to reduce greenhouse gas emissions to levels which would abate such stresses. As a result the Convention, as it now stands, is incapable of protecting coral reefs. Even worse, adopting politically convenient targets for acceptable climate change which are far above the ability of corals to adapt effectively condemns coral reef organisms and cultures which depend on them to extinction. This abdication of responsibility makes the entire Convention meaningless, analogous to the original targets adopted by the Montreal Protocol on Substances which Deplete the Ozone Layer, which were completely inadequate to restore the ozone layer. The international community was forced to abandon those original meaningless targets and adopt much more stringent criteria in order to significantly reduce ozone depletion. We urge the negotiating parties to the Framework Convention on Climate Change to recognize that a serious error has been made in setting acceptable rates for global warming which are inadequate to protect climate-sensitive ecosystems. and to adopt much more stringent criteria which can protect the ecosystems and economies of the coral reef countries. 2) Honest accounting of greenhouse gas sources and sinks In a last minute change of wording which took place late at night on the final day of the final United Nations meetings of Convention negotiators before the Rio de Janeiro Earth Summit, countries were required to account for only the anthropogenic (human-caused) sources of greenhouse gases but for all (both anthropogenic and natural) the sinks of greenhouse gases. This incredible flaw confuses net and gross flows by ignoring the natural sources which provide the vast majority of greenhouse gases in the atmosphere, and allows countries to claim huge, essentially fictitious, sinks of greenhouse gases while they need not account for the return of these gases to the atmosphere through natural biological and oceanographic cycles. This absurdity passed without comment from negotiating parties. Only the Global Coral Reef Alliance pointed out the error immediately, but without effect. Any financial officer who attempted such dishonest accounting with real money would be jailed. Accounting of all greenhouse gas inputs and outputs. both man-made and natural. needs to be complete and done on the same basis. Not doing so will allow countries to obtain huge credits for non-existent carbon sinks on land and in the sea which will make a mockery of any efforts to stabilize greenhouse gases. We urge delegates to resolve this intrinsic flaw in the Convention. 3) Reforestation to stabilize carbon dioxide concentrations Any effort to stabilize carbon dioxide levels must ensure that the sinks of this gas equal its sources, yet the present situation, and all scenarios for stabilizing emissions (as opposed to actually stabilizing concentrations of greenhouse gases) result in a large and unbalanced excess of sources over sinks which will result in a continuing increase of greenhouse gases in the atmosphere. While a transition away from fossil fuels cannot take place rapidly, due to the lack of available cost-competitive renewable alternative energy sources for vehicular transport, the imbalance can be readily eliminated by increasing reforestation on a scale which would absorb the carbon dioxide produced. This requires funds for replanting of trees on a scale adequate to remove the excess by recycling carbon dioxide into increased biomass. Sadly almost every country in the world now has deforestation rates which greatly exceed reforestation rates. Panama may be the only country where massive tree planting is close to stabilizing the national carbon balance with the atmosphere. More than ten years ago many of us researching tropical rainforest carbon balances pointed out that huge areas which have been deforested and converted to worthless abandoned scrub with no economic use are more than adequate to absorb the global excess of carbon dioxide if replanted with trees. Economic assessments showed that this was technically feasible and could be done at a cost of only a few dollars per person per year. If we apply the "polluter pays principle" and allocate carbon removal costs to those who consume fossil fuels which add excess carbon dioxide to the atmosphere, it would have only a very minor impact on fuel prices. Unfortunately proposals for a "carbon balance tax", which would be used to directly solve the greenhouse gas stabilization problem by paying the direct costs of carbon removal, has been confused with very different concepts of a "carbon tax" proposed by economists and politicians. Their carbon taxes, instead of being specifically designed to stabilize greenhouse gas concentrations, are intended instead to raise the cost of energy to such levels that people are forced to reduce energy consumption because it is too expensive. This is a punitive tax which must significantly raise energy costs to have any significant impact, and is designed to generate discretionary revenue for politicians to spend without actually solving the global environmental problems caused by greenhouse gas emissions. Punitive-type carbon taxes will unacceptably reduce standards of living without solving the atmospheric buildup problems created by fossil fuels. We urge instead that a "carbon balance tax" be adopted which is specifically targeted at carbon dioxide stabilization. This could solve the environmental problem at a cost which would not be punitive or inflationary. It could be politically acceptable to consumers if it is transparently used and targeted at the scale needed to be effective. unlike taxes which punish energy users and disappear into general revenues spent according to ephemeral political "needs" and whims. We urge delegates to look at the larger global picture of carbon dioxide stabilization by balancing worldwide supply and demand. rather than focusing on national quotas for emissions which are not sufficient by themselves to solve the problem. 4) Solar power development In the long run the only feasible solution to global climate change problems is to switch from fossil fuels like oil, coal, and natural gas to renewable energy sources which do not produce greenhouse gases. Most renewable energy sources, such as wind, tides, hydroelectric, and geothermal energy, are so sparsely distributed that although they can be profitably used by those fortunate to live next to areas with unusually high winds, tides, waterfalls, or volcanic heat, they can only provide a very small contribution to global energy needs. Wave and ocean current energy have the potential to provide major energy sources, but the technology to tap them has not yet been adequately developed or shown to be cost effective. Only one renewable energy source has been shown to be technically feasible and adequate in magnitude to provide a major fraction of global energy needs, namely solar energy in the form of electricity generated by photovoltaic panels. Although the cost of solar electricity is steadily falling, it is still more expensive than conventional electricity generated by burning fossil fuels, except for new installations which are remote from existing power grids. There is great promise of technological improvements with new materials which could drive down prices even further, such as amorphous silicon or organic semiconductors, and solar energy costs should become less than fossil fuel electricity within a decade or so if current trends continue. This time delay is an artificial problem that is the result of lack of mass production of photovoltaic cells, which would quickly drive the price down to the point where they were competitive. Lack of mass production results from lack of large scale investment in manufacturing facilities because the major market is in poor tropical countries which cannot afford the technology until it is cheaper than conventional energy sources, and the fact that virtually all solar cell manufacturers are owned by oil companies. They recognize that eventually solar energy will inevitably become cheaper as solar cell production costs fall and as cheaply extracted fossil fuels are used up, and when that happens they want to continue to be the major energy suppliers. However they don't want the transition to happen until they get the maximum profits from existing investments in extraction, shipping, and refining of fossil fuels. The world's largest solar power plant, which was built in cold Michigan, worked perfectly well until it was bought by an oil company which dismantled it and sold off the used solar panels at bargain prices (the Global Coral Reef Alliance was fortunate to purchase the last case of these solar panels for use in its reef restoration programs). A rapid transition to solar power would be the best thing for the global environment, and could be jump started if the world community were to invest in large scale manufacturing facilities in countries rich in human technical skills like China, India, and Brazil, which would drive the price of panels down and make solar electricity cheaper than fossil fuel plants, and eliminate most global sources of greenhouse gases. While it would not immediately allow replacement of petroleum in vehicles, due to the weight and limited range of fuel cells, investment could be made in use of solar electricity to hydrolyze water to produce non-polluting hydrogen fuels which could replace petroleum in vehicles. We urge delegates to the Climate Change Convention to recognize that the real solution to the climate change problem is to end our reliance on polluting fossil fuels. and make alternative. clean. renewable energy affordable by promoting large scale investment in solar technology so the transition to a renewable energy economy can take place before the environmental damage caused by fossil fuels is irreversible or excessively costly to remediate. 5) Mineral accretion to protect shores. adapt to sea level rise. and restore reefs Coastal erosion is a worldwide problem exacerbated by a global average sea level rise of 2 millimeters per year, and which will accelerate rapidly unless global warming is controlled. The problem is especially severe along tropical coasts which were formerly protected by healthy coral reefs that have been damaged and are no longer able to protect the shore from waves. Healthy coral reefs are the only ecosystem capable of building a growing wave-breaking barrier that can grow upward as fast as sea level rises, and under good conditions they grow even faster than sea level rise, building land. These conditions are only possible with healthy corals. When corals are sick or die, the reef is broken down by erosion, and slowly vanishes. The maximum growth rate of reefs is only a fraction of the rate of growth of the corals themselves, as most coral growth is ultimately broken down to form rubble and sand, and the solid reef barrier can grow upwards at no more than a maximum of about 3 or 4 millimeters per year. At present only the healthiest coral reefs are able to keep up with sea level rise, and the great majority are now falling behind as sea surface moves up by 2 mm per year. Even at the current rate of sea level rise, reef after reef which was historically able to keep pace is now falling behind. The worst situation is along populated coastlines where the need for coastal protection is greatest. If sea level rise were to increase by only 2 mm per year, virtually no reef could keep up. Uncontrolled climate change would make this a certainty. Indeed during the last great melting of the ice caps, it is estimated that sea level rose by over 100 mm per year! Reefs along most populated shores are dying as sewage and fertilizers washed into the sea, rivers, and groundwaters are increasing the concentrations of nitrogen and phosphorus nutrients in the coastal zone, causing over-fertilization of weedy algae, which then over-grow and kill the corals. Jamaican reefs, formerly among the best in the Caribbean, are now almost entirely dead as the result of massive proliferation of algae. Similar expansion of algae is seen around the world wherever development exceeds the capacity of the reef to survive. The crumbling reef framework is unable to grow upwards and break the waves, so rates of coastal erosion have greatly accelerated. Weedy algae have killed the sand-producing organisms, so there is no new supply of sand to replace that which is increasingly being lost to erosion. This pattern is found wherever coastal development proceeds without appropriate technology to absorb excess nutrients on land before they damage the sea. Technologies which recycle the nutrients to increase growth of plants on land instead of killing the reefs are readily available but rarely used. By using waste nutrients to fertilize land plants which absorb them before they reach the sea, we have been able to rapidly eliminate the weedy algae which had been smothering coral reefs, eliminating old costs while simultaneously providing new benefits. Coastal reefs are also dying by being smothered by soils which have been eroded from land after deforestation of coastal watersheds. Corals worldwide are being killed by outbreaks of new coral diseases. Currently diseases are worst in the Caribbean, where we are tracking the spread of over a dozen different coral reef diseases killing corals, sponges, and algae, but we find diseases at lower levels almost everywhere in the Pacific and Indian Oceans as well. Wherever corals bleach, they completely stop growing, sometimes for over a year, until they recover or die. Humans also speed up coral death by coral mining, siltation following coastal dredging, anchor damage, dynamite, poison fishing, trampling by divers and snorkelers, toxic chemical releases, and other means. Damage can also result from natural causes such as hurricanes, typhoons, and cyclones, or the crown of thorns starfish. Where the reef is free from all human stress they can recover from natural damage, but where they are subjected to increasing stress from human impact, there is little or no recovery. The result of all these factors is greatly increased coastal erosion along most tropical coastlines. The situation is most threatening in the low lying islands which lie just above the high tide mark, whose very survival requires healthy coral reefs. Whole nations such as the Maldives, Kiribati, Tuvalu, Tokelau, and the Marshall Islands could vanish if sea level rise continues, along with many other populated low lying island groups. The costs of coastal protection are staggering. After the reefs around Male, the capital island of the Maldives, which has 80,000 people living on 2 square kilometers, were mined out, the island was flooded by storm waves in 1987. A concrete wall was built around the island, at a cost of nearly $10,000 per meter, or $10 million per kilometer. Other populated Maldivian islands which do not have the funds for concrete walls have mined corals to build rock walls, destroying permanent growing reef barriers to make temporary ones which will eventually be broken apart by storm waves. The costs of seawalls will be astronomical in the coming years, even without further rise in sea level. A new technology developed by Wolf Hilbertz and the author of this article can grow limestone structures in the sea. The process, named "Mineral Accretion", uses low, safe electrical currents to cause limestone rock to be precipitated out of seawater and to grow on top of structures which can be built in any shape and size. These structures can grow upwards at over 10 millimeters per year, and corals which are transplanted onto them, or settle naturally on them, grow at accelerated rates. All components of a natural coral reef migrate onto them, restoring coral reefs in a way that does not happen on artificial substrates such as sunken cars, ships, planes, rubber tires, concrete blocks, stones, or fly ash. The structures do not rust or corrode, become stronger with age, and are self-repairing: any cracks or damage are filled in as long as the electrical current flows. The cost of shore protection structures recently built at Ihuru Island in the Maldives using mineral accretion are less than one tenth the cost of conventional shore protection methods using cement, stone, or sand bags. The electricity can be supplied using DC converters supplied by fossil fuel generated alternating current, but we prefer to use solar panels, windmills, or ocean tidal current generators. Mineral Accretion is the best and cheapest possible alternative for protecting shorelines from erosion and restoring reef ecosystems under conditions of climate change and increasing human stress to reefs, but it has yet to be widely applied because of its novelty and since few people are aware of successful pilot projects in the Maldives, Seychelles, and other places. The world needs large scale investment in cost-effective shore protection to adapt to global change. Mineral accretion technology would save vast sums. and its application should play a central role wherever erosion is a problem. Because of the need for electricity. often at remote locations, the new technology will be best suited to use of solar panels. and will be most beneficial if their production costs are further reduced. and if sea level rise is limited by stabilizing greenhouse as concentrations. 6) Increased energy efficiency Little need be said about this, as it is obvious to everyone that technical improvements which allow the same work to be done with less energy will result in reduced greenhouse gas emissions, and this is high on every list of mitigation options. Such technical improvements are by nature unpredictable, and while we can count on human ingenuity to continually find new ways to better the situation it would be utopian to count on this alone to solve the problem. Policy steps in all the other directions are needed anyway, and if sufficiently large energy efficiency improvements can be achieved, they will provide a welcome bonus which can reduce the magnitude of investment in some of the other steps needed to halt global climate change. But by themselves they are unlikely to eliminate the need for them. C. CONCLUSIONS The purpose of this briefing is not to criticize IPCC's monumental work but to add to it by pointing out some critical issues which it has underestimated. IPCC has attempted the vast and crucially important effort of summarizing a huge published technical literature, some of it good, some of it poor, much of it simply irrelevant. In doing so, the importance and vulnerability of coral reefs has been given serious short shrift, and their role as the most climatically endangered ecosystem, their inability to tolerate further climate change, and their "canary in the mine" role indicating that serious and irreparable damage will result from global warming have been virtually ignored. We believe that worldwide climatic damage to the most species-rich, productive, economically-important, and beautiful marine ecosystem is already taking place, and that prevention of further climate change will irreparably damage or completely terminate the invaluable natural services which coral reefs provide for free, causing untold environmental and economic damage to over a hundred countries. Climate change impacts are not just a potential risk for future generations, they are taking place right now before our eyes, as reef after reef turns white and stops growing, and as corals increasingly die from heat. Urgent action to protect coral reefs and the species. people. and countries which rely on them from damage caused by uncontrolled global change is an immediate necessity. If such steps are not taken by the Framework Convention on Climate Change. coral reef ecosystems will die. Steps to halt global climate change and save reefs are technically feasible and economically rewarding in the long run, because they are the steps we need to take anyway. The sooner we do so. the less will be both the damage and the cost. and the greater will be the benefits for ourselves and for future generations. We urge the delegates to the negotiations on the Framework Convention on Climate Change to transcend short term national and political perspectives and live up to their long term global responsibilities. The author: Dr. Thomas Goreau is President of the Global Coral Reef Alliance. Previously Senior Scientific Affairs Officer at the United Nations Centre for Science and Technology for Development, he was educated in Jamaican schools, MIT, Caltech, and Harvard. He has worked on the full range of coral reef conservation and management problems across the Caribbean, Pacific, and Indian Oceans, the effects of Amazon deforestation on the chemistry of the atmosphere, planetary astronomy, and other issues. For more information on matters in this briefing, please contact him at the above listed Global Coral Reef Alliance contact addresses. As he is in the field studying coral reefs most of the time he often cannot respond quickly. |
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