Coral Reef Death ..

CORAL REEF DEATH LINKED TO TROPICAL
WILDFIRES IN INDONESIA DURING THE 1997
INDIAN OCEAN DIPOLE

N.J. Abram (1), M.K. Gagan (1), J. Chappell (1),
M.T. McCulloch (1), W.S. Hantoro (2)

The coral reefs of the Mentawai Islands, Indonesia, experienced catastrophic mortality of close to 100% of the coral and the fish during the 1997 Indian Ocean Dipole (IOD) upwelling event. The link between elevated sea surface temperatures (SST) and coral death is now well known, however the unanticipated Mentawai reef mortality coincided with anomalously cool SSTs and a giant red tide. Ocean productivity in the Indonesian region is generally proportional to the strength of upwelling; therefore the severity of the 1997 Mentawai reef death raises the question of whether the magnitude of the IOD upwelling and red tide during 1997 was unprecedented. Here we examine the tolerance of Mentawai corals to IOD upwelling events over the past 6,300 years using coral skeletal growth and palaeothermometry. High-resolution coral Sr/Ca and 18O reconstructions of SST reveal pre-historic IOD cold anomalies of up to 5.8C.

The magnitudes of these events exceed the strong 1997 IOD upwelling by as much as 1.9C, yet we find no evidence of past coral mortality. From these results it seems that the intensity of the 1997 Mentawai red tide was much greater than expected based on the magnitude of IOD upwelling alone. This implies that an additional source of nutrients must have supported the catastrophic red tide and we propose that these nutrients were provided by the 1997 Indonesian wildfires. These fires were the worst in south-east Asian history and were the combined results of land clearing, past forest disturbance and intense drought driven by the 1997 El Niño-Southern Oscillation and Indian Ocean Dipole events. Using mass balance calculations we show that ironfertilisation of the upwelled nutrient-enriched water by atmospheric fallout from the 1997 wildfires was sufficient to produce the extraordinary red tide, ultimately leading to the unprecedented death of the Mentawai reefs. These findings highlight the escalating phenomenon of tropical wildfire as a potential new threat to coastal marine ecosystems.

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(1) Research School of Earth Sciences, The Australian National University, Canberra ACT 0200, Australia, (2) Research and Development Center for Geotechnology, Indonesian Institute of Sciences, Bandung 40135, Indonesia.

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The Return of EL Niño

Will Warm Water Wreak Havoc When Winds Won’t Blow?

Well, it looks like the next El Niño is coming. Right now many scientists are observing warming over the Tropical Pacific, and this has led to predictions of the next El Niño. El Niño is known to scientists as the El Niño-Southern Oscillation, or ENSO, and is a complicated chain of events that begins in the Pacific Ocean and then spreads to affect the weather around the entire world. What is the El-Niño Southern Oscillation, you ask? The El-Niño Southern Oscillation is the result of a cyclic warming and cooling of the surface ocean of the central and eastern Pacific.

In normal, non-El Niño conditions the central and eastern Pacific region of the ocean is normally colder than its equatorial location would suggest. This condition exists because of the influence of trade winds blowing to the west, a cold ocean current flowing up the coast of Chile, and upwelling of cold deep water off the coast of Peru. The trade winds blow toward the west across the tropical Pacific and these winds pile up warm surface water in the west Pacific. The sea-surface temperatures are much colder near South America because of an upwelling of cold water from deeper levels. This cold water is extremely nutrient rich, leading to high levels of primary productivity, a rich ecosystem, and major fisheries off the coast of Peru.

During an El Niño event, the trade winds weaken in the central and western Pacific for unknown reasons. This weakening causes western Pacific waters to cool, and a warming in the eastern Pacific. The warm, still surface waters in the east Pacific reduce the efficiency of the cold nutrient-rich upwelling, which results in an even larger increase in sea surface temperatures and a dramatic decline in productivity that severely impacts marine life and commercial fisheries in this area. The warming waters in the east Pacific cause huge thunderstorms and floods in the Peru area, while the cooler water temperatures in the west Pacific cause problems such as droughts in Indonesia and Australia.

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The Indonesian Throughflow .....

The Indonesian Throughflow and the Global Climate System

Niklas Schneider

Climate Research Division, Scripps Institution of Oceanography, University of California,
San Diego, La Jolla, California

ABSTRACT

The role of the Indonesian Throughflow in the global climate system is investigated with a coupled ocean–atmosphere model by contrasting simulations with realistic throughflow and closed Indonesian passages.

The Indonesian Throughflow affects the oceanic circulation and thermocline depth around Australia and in the Indian Ocean as described in previous studies and explained by Sverdrup transports. An open throughflow thereby increases surface temperatures in the eastern Indian ocean, reduces temperatures in the equatorial Pacific, and shifts the warm pool and centers of deep convection in the atmosphere to the west. This control on sea surface temperature and deep convection affects atmospheric pressure in the entire Tropics and, via atmospheric teleconnections, in the midlatitudes. As a result, surface wind stress in the entire Tropics changes and meridional and zonal gradients of the tropical thermocline and associated currents increase in the Pacific and decrease in the Indian Ocean. The response includes an acceleration of the equatorial undercurrent in the Pacific, and a deceleration in the Indian Ocean. Thus the Indonesian Throughflow exerts significant control over the global climate in general and the tropical climate in particular.

Changes of surface fluxes in the Pacific warm pool region are consistent with the notion that shading by clouds, rather than increases of evaporation, limit highest surface temperatures in the open ocean of the western Pacific. In the marginal seas of the Pacific and in the Indian Ocean no such relationship is found. The feedback of the throughflow transport and its wind forcing is negative and suggests that this interplay cannot excite growing solution or lead to self-sustained oscillations of the ocean–atmosphere system. (full text)

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The Geostrophic Transport ....

Geostrophic transport of the Pacific-Indian Oceans throughflow : Pacific low-latitude western boundary currents and the Indonesian Throughflow

FIEUX M. (1) ; MOLCARD R. (1) ; ILAHUDE A. G.

Laboratoire d'Océanographie Dynamique et de Climatologie, CNRS/ORSTOM/UPMC,
Paris, FRANCE

Abstract

For the dynamic balance of the world ocean circulation, the flow through the Indonesian archipelago needs to be quantified. Part of the Java Australia Dynamic Experiment program was to occupy hydrographic sections during the two opposite seasons. Here we present and discuss the February 1992 geostrophic estimate of the throughflow. The appearance of the east flowing Java Current, flowing in the 80 km off the Indonesian coast, led to a net total transport of a few 106 m3 s-1 eastward, opposite to the expected sense of net transport. Uncertainty in this transport, estimated from the repeated casts, reaches 9 106 m3 s-1. This large error could be attributable to internal wave motions. Estimates of the transport from the conductivity-temperature-depth data and from the temperature profile associated to the Levitus [1982] data set have been compared. Comparison with August 1989 results shows that the main westward current, corresponding to the South Equatorial Current, is located north of the hydrological front in both seasons. The largest transport variation between the two cruises is located along the Indonesian coast, with the reversal of the Java Current. The mesoscale current variability is enhanced in the southern part of the section in February 1992. These transport evaluations, made in the two opposite seasons and in two different years, 18 ± 7 106 m s-1 westward in August 1989 and 2.6 ± 9 106 m3 s-1 eastward in February 1992, give an extreme range of the net throughflow. (source ..>>)

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El Nino, who are you ...?

When the 1997 Indonesian fires broke out in mid-May of that year, no one took too much notice, as it was the beginning of the dry season. When the monsoons that carried precious rain to douse the flames and for crop growing did not arrive, the fires soon burned out of control into firestorms. The burning was most severe in East Kalimantan, a section of Indonesian part of Borneo, and the island of Sumatra, where an estimated total of 10,000,000 hectares was either totally burned or badly ravaged by the fires. Haze and smoke from the fires spread across Indonesia and Southeast Asia. At its worst the haze spread halfway across the Indian Ocean to the Maldives, north to the Philippines and Thailand, east to Papua New Guinea, and across northern Australia (Appendix #1). The widespread haze caused numerous health problems, affecting approximately 70 million people and causing 20 million of them to become sick. When neighboring countries complained about the deadly haze, President Suharto made a rare public apology, referring to the poisonous haze from the fires as "an act of God."2 The latest estimate of the damages of the fires was about US$4.5 billion, although when added with the value of lost timber and crops, this total skyrocketed to almost $9 billion. As further analyses of the fire's damages are being conducted, this estimate might rise. But most of the costs were probably impossible to calculate, as the damage the fires and resulting haze had on the environment and ecosystem were priceless and irreplaceable. The new Environmental Minister Juwono Sudarsono under the new President B.J. Habibie estimated that it might cost $2 billion to effectively respond to the fires.3

an image of normal ocean temperature

an image of el nino

Global map of: 1) normal ocean temperature, 2) el nino

The normal fires and the haze from it were significantly enhanced by El Nino, a weather phenomenon where the abnormally warm sea surface temperatures cause global weather patterns to change, resulting in abnormal weather effects around the world. In Indonesia, El Nino caused a drought because the monsoon season was pushed back from September to mid-November, and a delayed and shortened monsoon season caused a second drought in Indonesia. Usually undisturbed rain forests are highly resistant to fire because of their moisture, but will burn in extreme droughts. Drought and millions of dead biomass on the forest floor from selective logging made entire forests extremely prone to fire. As a result, instead of the normal flames being doused by the monsoon rains, the flames were left to ignite whole forests into an inferno. In addition, regulated fires set by timber and agribusiness firms were left to burn to clear more land for profit. Taking advantage of the extra months of the dry season, peasants who burned small amounts of land each year for subsistence farming increased their plot to grow more food. When the delayed monsoon rains arrived in Indonesia in November 1997, an estimated 2 million hectares of lush rain forest, brush and grasslands were already decimated in Kalimantan and Sumatra alone, and when the inter-monsoon season began in January, fires were spotted again all across Sumatra and Kalimantan. The same deadly cycle of the 1997 fires arose again, with thick haze from the fires spreading throughout Indonesia, until this second round of conflagrations ended in late April when rains arrived, but Indonesian officials stated that the fires had been expunged because "there was nothing left to burn."4 In fact, El Nino and La Nina were predicted well before they had any effect on Indonesia, but many parties ignored the warning and continued their usual burning of the forest. (source ...>>)

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Ocean Wave Energy

Ocean wave energy is captured directly from surface waves or from pressure fluctuations below the surface.

Waves are caused by the wind blowing over the surface of the ocean. In many areas of the world, the wind blows with enough consistency and force to provide continuous waves. There is tremendous energy in the ocean waves. Wave power devices extract energy directly from the surface motion of ocean waves or from pressure fluctuations below the surface.

Wave power varies considerably in different parts of the world, and wave energy can't be harnessed effectively everywhere. Wave-power rich areas of the world include the western coasts of Scotland, northern Canada, southern Africa, Australia, and the northwestern coasts of the United States.

Ocean Wave Energy Technologies

A variety of technologies have been proposed to capture the energy from waves. Some of the more promising designs are undergoing demonstration testing at commercial scales.

Wave technologies have been designed to be installed in nearshore, offshore, and far offshore locations. The OCS Alternative Energy Programmatic EIS is concerned primarily with offshore and far offshore wave technologies. Offshore systems are situated in deep water, typically of more than 40 meters (131 feet).

While all wave energy technologies are intended to be installed at or near the water's surface,they differ in their orientation to the waves with which they are interacting and in the manner in which they convert the energy of the waves into other energy forms, usually electricity. The following wave technologies have been the target of recent development.

Terminator devices extend perpendicular to the direction of wave travel and capture or reflect the power of the wave. These devices are typically onshore or nearshore; however, floating versions have been designed for offshore applications. The oscillating water column is a form of terminator in which water enters through a subsurface opening into a chamber with air trapped above it. The wave action causes the captured water column to move up and down like a piston to force the air though an opening connected to a turbine.

A point absorber is a floating structure with components that move relative to each other due towave action (e.g., a floating buoy inside a fixed cylinder). The relative motion is used to drive electromechanical or hydraulic energy converters.

1) Rendition of a Wave Farm Made Up of Permanent Magnet Linear Generator Buoys; 2)Point Absorber Wave Energy Farm; 3); Animation of Point Absorber Operation

Attenuators are long multisegment floating structures oriented parallel to the direction of the waves. The differing heights of waves along the length of the device causes flexing where the segments connect, and this flexing is connected to hydraulic pumps or other converters.

Overtopping devices have reservoirs that are filled by incomingwaves o levels above the average surrounding ocean. The water is then released, and gravity causes it to fall back toward the ocean surface. The energy of the falling water is used to turn hydro turbines. Specially built seagoing vessels can also capture the energy of offshore waves. These floating platforms create electricity by funneling waves through internal turbines and then back into the sea.

Environmental Considerations

Potential environmental considerations for the development of wave energy include the following:

# Positive or negative impacts on marine habitat (depending on the nature of additional submerged surfaces, above-water platforms, and changes in the seafloor);

# Toxic releases from leaks or accidental spills of liquids used in those systems with working hydraulic fluids;

# Visual and noise impacts (device-specific, with considerable variability in visible freeboard height and noise generation above and below the water surface);

# Conflict with other sea space users, such as commercial shipping and recreational boating; (source ...>>)

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Blue Energy [2]

Blue Energy Market Driver Global warming - Carbon Dioxide emissions are projected to grow by 70% by 2020 and to double by the year 2050 unless new policies are put in place to reduce them. Intergovernmental Panel on Climate Change reports this would result in an average global temperature increase of 3.5 degrees Centigrade by the middle of this century. A 60 to 80% cut in greenhouse gas emissions will ultimately be needed to stabilize atmospheric concentrations of the gasses and avert serious climate disruptions. This will require a massive global transition to renewable energy sources and large improvements in energy efficiency.
Transportation - Builders of large bridge infrastructure recognize the advantages of a sustainable transportation solution as the lucrative energy stream offsets the need for instituting onerous user tolls for new bridges. The tops of the machinery rooms are continuous and support a four lane roadbed for vehicular traffic, either along the top of the tidal fence, or stackable lanes within the structure.
Declining Demand for Nuclear Power - The public is evermore wary of nuclear weapons proliferation spawned from unregulated nuclear power programs. Chernobyl, Three Mile Island, and recent nuclear accidents in Japan have brought the world’s attention to the dangers of nuclear power. A widespread resolve is developing for the rapid phase out of nuclear facilities in western and central Europe and in North America. In the last decade, nuclear power has gone from being the world’s fastest-growing energy source to its second slowest.
Declining Coal Use - Coals share of world energy is down to 23%, roughly where it was in 1860. China has more than halved its coal subsidy rates singe 1984, a move which contributed to a 5.2% drop in domestic coal consumption in 1998. Belgium, France, Japan, Spain, and the United Kingdom have collectively halved coal use since slashing or ending coal supports over the last fifteen years. With growing legal liability and possibility of severe emissions penalties for coal production as outlined in Kyoto Protocol, the reign of “King Coal” may soon be brought to a timely end in the early part of the new millennium.
Dwindling Supply of Peak Oil Reserves - Approximately 80% of the oil produced today comes from fields discovered before 1973, most of which are in decline. A recent analysis of data on world oil resources estimates that roughly one trillion barrels of oil remain to be extracted from the earth. With an estimated 800 million barrels already extracted and present levels of consumption, this data suggests that world oil production could peak between 2000 and 2010, and then begin a decline throughout the remainder of the century, accompanied by increasingly higher prices.
Increased Opposition to Hydro Electric Dams - Hydroelectricity is well established in North America, but has limited potential for further development worldwide due to environmental impacts. Fifty percent of the natural gas burned today comes from wells drilled in the last three years. The relatively new phenomenon of breaching is gaining in popularity, as the ecological devastation of large scale dams is being felt in widespread extinction of fish species. The economic costs of renewing fish stocks or erecting fish ladders are often more costly than removing the dams altogether.
Increasing Demand for Renewable Energy Sources - To counter the effects of global warming from the combustion of fossil fuels, a rapid shift towards renewable energy development is now underway. Economic projections indicate that this trend will continue to accelerate rapidly. Wind and solar power developments have been leading the way with annual capacity increases of 25.7% and 16.8% respectively between 1990 and 1997, and are still growing markets today.
Deregulation of Energy Markets - For the first time in many decades energy consumers in countries around the world are being given a choice of who supplies their electric power and how that power is generated. Similar to the restructuring of the telecommunications industry in the mid- 1980's, the introduction of competition in power markets is giving customers more options, one of which is to purchase electricity from renewable sources.

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Blue Energy [1]

Tidal Power

There are basically two methodologies for creating tidal power: the use of tidal dams or ocean currents. Dams are based on using a barrage at a bay or estuary with a large tidal range. Power is generated primarily at ebb tides as the barrage creates a significant head of water, much like a hydroelectric dam. This technology is very well established at La Rance, France where a 240MW plant has operated since 1966. A 20MW facility has also been present in Annapolis, Nova Scotia since 1984. However, estuaries are amongst the world’s most productive and sensitive ecosystems, and the flooding by these barrages causes a great disruption to their natural processes. In the context of ocean energy, barrage based tidal power is not considered a truly sustainable resource.

The sources of Blue Energy’s tidal power production are fast flowing tidal currents. The gravitational pull of the moon causes water to flow in from the ocean twice a day on the flood tides, and outward during ebb tides. Additional monthly and annual lunar cycles vary the strength of these currents. Narrow and shallow constrictions produce the fastest and most powerful movements of current, whose energy can be harnessed using the Blue Energy Ocean Turbine. This energy source is independent of weather and climate change and follows the predictable relationship of the lunar orbit that is known many years in advance.

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