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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Raja Ampat Islands Contain World's Richest Coral Reefs

Some of the most experienced marine scientists tropical, led by The Nature Conservancy, conducted a three-week expedition to the Indonesian islands of Raja Ampat, where they confirmed that the region contains the richest coral reefs the world.

The Raja Ampat islands west of Sorong, on the northwestern tip of the island of New Guinea in the province of Papua in Indonesia. The four main islands - Waigeo, Batanta, Salawati and Misool - and their thousands of satellite islands cover an area of some 23,630 square kilometers (61200 square kilometers).


Scientists have found that the number of reef fish and coral species in the region is even greater than expected. At least 465 species of coral have been recorded, with at least 20 species to defy identification and study in others. This brings the total confirmed corals of the Raja Ampat islands to 505 species, an incredible 64% of all species of coral in the world (for the most recent estimates of numbers, see our report of the investigation in 2006 on the ).

During this trip, 828 species of fish have been recorded, adding an additional 95 (including four new to Indonesia) and increasing the total known to Raja Ampat to 1065 species - among the highest in diversity the world. A new personal record of 284 species of fish on one dive was set by Dr. Gerry Allen Kofiau to the island. When laboratory results on marine samples are completed, scientists expect to find species of fish and corals that are new to science.

"The waters around the Raja Ampat islands teeming with a diversity of corals and fish than anywhere else in the world," said Steve McCormick, president of The Nature Conservancy. "This place is at the heart of the heart of marine biodiversity, and every effort must be made to retain it."

"While we continue to see reports decimated and degraded marine ecosystems and in the west of central Indonesia, the survey clearly demonstrates that it is still a chance to retain important island of high quality and reef ecosystems in Indonesia, "said the conservation of Indonesia Country Director, Dr Ian Dutton. "Conservation is working in partnership with local communities and government, universities and industry partners to protect this wonderful region."

Raja Ampat has become an administrative region or kabupaten, and it is feared that the need to increase local revenue will allow the widespread extraction of natural resources. The results of this study marine and maps will be presented to local communities to raise awareness of the richness of biodiversity that the region has and solicit ideas on how best to keep it. It will help the local government establishes environmentally sensitive development plans, and contribute to the conservation and other conservation organizations to determine the best way to protect this remote tropical paradise.

"The customary ownership of resources and traditions of the region means that some reefs have escaped the ravages common to many other reefs of South-East Asia," said Dr. Rod Salm, director of the conservation of coastal marine conservation in the Asia-Pacific. "It's really an excellent opportunity to develop a conservation program with communities that have a strong personal and historic commitment to manage their resources sustainably."

Scientists have found many Raja Ampat coral reefs to be in good condition despite the rampant destruction reefs often seen in Southeast Asia. Parts of reefs damaged by the blast and cyanide fishing has shown a good recovery, and there was little evidence of the extensive coral bleaching that devastated reefs in many parts of the world following the 1998 El Niño. The fact that coral bleaching resisted confirms their resilience and value as a source of larvae to assist in the recovery of damaged reefs widely throughout Indonesia, Philippines, Papua New Guinea and Micronesia .

The team also noted a virtual absence of sharks during the trip - only three sharks were seen in 500 hours under water. Over fishing has caused a sharp drop in the Raja Ampat population of sharks. Shark fins are highly valued as a soup ingredient in Asia. There are about 200 shark-fishing boats operating in this area, and each is estimated catches of 240 per month. Once the fins are removed, the bodies are left to rot on the reefs. The removal of the ecosystem of predators is only one of the adverse effects of human activities on reefs - The buzz of chain saws, the crash of falling trees, and the bombing and cyanide fishing still widely practiced, and turtles are overexploited for each location they nest.

Ground crews have found many unique habitats in Raja Ampat, especially the broken-bottle limestone karst landscape, and rich mineral soil the northern islands. Around these islands in the extreme habitat has led to high levels of endemism - that diversity is low, most species of plants are found only in this particular habitat. Several potentially new species of plants were discovered, including a new species of flowering plant tropical Psychotria Kawe on the island.

Local communities are very concerned about damage to their environment on the whole, they depend on marine resources for their livelihood. Extractive industries such as logging and commercial fishing threaten to destroy the rich diversity of plant and animal life in these remote islands. Still, researchers on the socio-economic team was told by villagers that they feel powerless to counter the raiders outside resources that are more damage because they are often supported by powerful commercial and government interests.

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