Connectivity plays a fundamental role in ecological processes by facilitating the exchange of energy and materials in coastal environments. However, its influence on carbon dynamics within coastal ecosystems remains poorly understood. This study investigated the role of ecological connectivity in affecting sedimentary carbon sources and stocks across a range of interconnected coastal habitats in Berau Coastal Waters, Indonesia, ranging from the transition area to upland vegetation, estuarine mangroves, intertidal mudflats, seagrass meadows, and carbonate mangroves on offshore islands. Sediment samples were collected using a 1-meter-long semi-cylindrical hand auger and were analysed for elemental and isotopic compositions. A Bayesian isotopic mixing model was applied to estimate the relative contributions of different organic matter (OM) sources to sedimentary carbon. The transition area and mangrove ecosystems exhibited comparable average sediment carbon stocks (similar to 202 Mg C ha(-1)), higher than those in the intertidal mudflats (151 Mg C ha(-1)), despite the absence of vegetation in the latter. The mangrove-derived OM contributed approximately 42-55% of the sedimentary carbon in the transition area, mangrove ecosystem, mudflat, followed by terrestrial plants-derived OM (26-35%). A declining trend in land-based OM was observed along the land-to-sea gradient, with contributions decreasing from similar to 37% to seagrass sediment at Rabu-Rabu Island to similar to 19% at Panjang Island. These findings suggest that both distance from source and hydrodynamic forces (e.g., tides and currents) play key roles in transporting OM across the coastal interface. The Berau coastal system thus functions not only as a carbon sink but also as a carbon transport pathway, linking green carbon from terrestrial sources to the blue carbon stored in marine sediments. Recognising and managing this ecological connectivity is essential for maintaining sediment carbon stocks and has important implications for climate change mitigation and carbon crediting frameworks, especially those requiring deductions for allochthonous carbon inputs.

Located on the northern coast of Java Island, the coastal area of Cirebon is an area with rapid population growth and extensively developed as settlement areas, industrial estates, fisheries, agriculture, and public service infrastructures. Coastal dynamics issues have been occurring in the coastal area of Cirebon, which is characterized by significant changes in shoreline position. Moreover, some critical infrastructures are not functioning properly and may cause high maintenance costs and economic loss to the related stakeholders. This study aims to provide a greater understanding of the coastal dynamics along the 73.16 km of Cirebon shoreline through remote sensing and GIS methods supported by hydrodynamic analysis. This study applied coastal characterization, coastal structure identifications, and coastal processes assessments, including erosion and accretion analysis, hydrodynamic and tidal analysis, and inundation projection. The study indicates that some areas have been subject to significant erosion and accretion during the last two decades, with the total lengths of the eroded and accreted shoreline being -21.9 km (35.6%) and +39.6 km (64.4%), respectively. Furthermore, the coastal structures significantly influence the coastline's dynamic and mitigate the negative impacts of coastal floods. Jetty access channels in the west area have caused partial coastal erosion, while the breakwaters in the east area accelerated sedimentation processes and improved the growth of mangroves simultaneously. This study also simulated the potentially inundated areas by 2050 in four scenarios based on projected sea level rise, land subsidence, and extreme wave events. Policies to prevent such potential hazards are needed to avoid negative impacts on the living quality and vital economic sectors. This study provides insight into coastal characterization, potential coastal hazards, and their driving processes in time and space scale for coastal adaptation planning policies and sustainable coastal hazard management and mitigation.& COPY; 2023 Elsevier B.V. All rights reserved.

Water availability and management for water security on small islands are critical. The purpose of this research is to uncover the water resources issue at a small island community level as well as discourse on the potential threats and sustainable management for water security. Tunda Island, located in the Java Sea, is one of 81 small islands in Banten Province, Indonesia. Data were collected through focus group discussions, open interviews with key persons, direct field observations, and secondary data gathering. Moreover, we analyzed time series climate data, particularly rainfall and population growth projections, based on data from official Indonesian government sites. The monthly mean precipitation is ranging from a low of 48 mm/month in August to a high of 292 mm/month in January. A “surplus of water” occurs from November to May, while months with a “deficit of water” occur from June to October. The majority of the community is unaware of the water security issue due to a lack of information and knowledge in the community. Some threats to the sustainability of water resources would be caused by two factors, both anthropogenical and natural: rising water demand, diminishing groundwater reserves due to population growth and tourism activities on the island, drought, sea level rise, and seawater intrusion as climate-related impacts due to increasing population growth and tourism activities on the island and drought, sea level rise and seawater intrusion as climate-related impacts. Developing community knowledge and awareness of water security is the main issue that should be handled first, coinciding with sustainable management practices that consider water use efficiency, the use of alternative water sources (e.g., rainwater harvesting), and protecting and restoring coastal ecosystems, especially for the future tourist destination.

Blue carbon ecosystems in the Karimunjawa Islands may play a vital role in absorbing and storing the releasing carbon from the Java Sea. The present study investigated mangrove above-ground biomass (AGB) and carbon stock in the Karimunjawa-Kemujan Islands, the largest mangrove area in the Karimunjawa Islands. Taking the aerial photos from an Unmanned Aerial Vehicle combined with Global Navigation Satellite System (GNSS) measurements, we generated Digital Surface Model (DSM) and Digital Terrain Model (DTM) with high accuracy. We calculated mangrove canopy height by subtracting DSM from DTM and then converted it into Lorey’s height. The highest mangrove canopy is located along the coastline facing the sea, ranging from 8 m to 15 m. Stunted mangroves 1 m to 8 m in height are detected mainly in the inner areas. AGBs were calculated using an allometric equation destined for the Southeast and East Asia region. Above-ground carbon biomass is half of AGB. The AGB and carbon biomass of mangroves in the Karimunjawa-Kemujan Islands range from 8 Mg/ha to 328 Mg/ha, and from 4 MgC/ha to 164 MgC/ha, respectively. With a total area of 238.98 ha, the potential above-ground carbon stored in the study area is estimated as 16,555.46 Mg.

Muara Gembong merupakan daerah yang mengalami tekanan antropogenik yang memberikan dampak signifikan bagi ekosistem pesisir di wilayah Teluk Jakarta. Riset ini bertujuan untuk menilai kondisi ekosistem mangrove, menghitung biomasa dan jumlah karbon yang tersimpan di dalam vegetasi mangrove per satuan luas (hektar) guna menentukan nilai moneternya. Riset dilakukan dengan pengamatan dan pengukuran mangrove untuk mengidentifikasi jenis mangrove, jumlah tegakan serta mengukur diameter batang pohon mangrove. Hasil riset menunjukkan bahwa rata-rata biomass dan karbon yang tersimpan di ekosistem mangrove Muara Gembong adalah sebesar 258,81 Mg/ha dan 119,97 Mg C/ha. Potensi kehilangan nilai ekonomi akibat kehilangan karbon ditaksirkan berkisar antara 1,15-2,84 x 1011 rupiah atau setara dengan 2,7-6,7 milyar per tahun. Kondisi kerusakan diperparah dengan adanya serangan hama, abrasi dan sampah. Dibutuhkan skenario rehabilitasi dengan memperhitungkan luasan area mangrove yang terdampak serta besarnya nilai kerugian moneter akibat kerusakan dan jasa ekosistem mangrove yang hilang.

Belowground root biomass plays an essential role in the mangrove ecosystem as potential carbon storage, nutrient gain, or sediment accumulation yet is still overlooked. Therefore, estimation of root biomass is necessary. The objective was to determine and compare the belowground root biomass at the natural and planted mangrove ecosystem. We also measured the forest structure and the aboveground biomass. This study was conducted at four stations in Pramuka Island, Pari Island, Rambut Island (2 stations), Seribu Islands, Jakarta. The first island represented planted mangroves, whereas the latter two as natural stems. Rhizophora stylosa was the dominant species in three stations except for Rambut Island 2 that dominated by Ceriops Tagal. Stand densities were 2730±5 stems ha-1, 1733±5 stems ha-1, 1311±2 stems ha-1, and 1300±2 stems ha-1 for Pramuka Island, Pari Island, Rambut Island 1 and 2. The highest pile density was counted in Rambut Island 2 for 1612±8 stems ha-1 and the lowest in Pramuka Island (780±5 stems ha-1). The aboveground biomass was estimated as follows 109.13±11.91 Mg ha-1 in Pari Island, 89.45±19.53 in Rambut Island 2, 68.41±17.12 Mg ha-1 in Rambut Island 1, and 14.05±5.74 Mg ha-1 in Pramuka Island. Belowground root biomass in planted mangrove Pramuka Island (3.63±0.82 Mg ha-1) and the other two natural mangroves Pari Island (6.56±0.47 Mg ha-1) and Rambut Island 1 (7.17±0.81 Mg ha-1), were similar except for Rambut Island 2 (49.23±6.77 Mg ha-1). The contribution of root biomass ranges from 6-24% of the total biomass of mangrove trees, whereas the fine roots (< 2 mm) biomass occurred 28-74% in the entire root biomass. The results confirm the high contribution of belowground root biomass to the total biomass pool and the importance of maintaining the planted mangrove as a part of ecosystem rehabilitation.

North Sulawesi is one of the provinces that implements national / regional action plan (RAN / RAD) policies as part of a national effort to climate change mitigation. One of the land-based mitigation activities in North Sulawesi is to measure and monitore biomass and carbon stocks in forests including coastal forests where the measurement area is still limited. In 2013-2015, Blue Carbon Research Group conducted research in four locations in North Sulawesi, which aims to analyze the ecological conditions and the ability of coastal ecosystems, especially mangrove in sequestering carbon. Study sites situated in Ratatotok - Southeast Minahasa Regency, Kema - North Minahasa Regency, Lembeh Island – Bitung City and Sangihe Island – Sangihe Regency. A total of 17 species identified where B. gymnorrhiza, R. mucronata and S. alba found in all locations. Species diversity ranges from low to moderate, where species distribution is uneven. Carbon storage capacity is equal to 343.85 Mg C ha-1 in Ratatotok, 254,35 Mg C ha-1 in Lembeh, 387,95 Mg C ha-1 in Kema and 594,83 Mg C ha-1 in Sangihe. More than 59% of carbon storage are in the sediment. The average value of carbon storage in the four research sites is 456,86 Mg C ha-1 or 5,70 Tg C after converted to a total area of mangrove ecosystems in North Sulawesi. The value is equal to absorption of atmospheric CO2 by 20.70 Tg CO2e. Potential emission due to changes in mangrove conversion reach 0.42 Tg CO2e. Efforts to increase the contribution of reducing North Sulawesi emissions can be achieved by implementing emission reduction interventions through the rehabilitation and conservation of mangrove ecosystems.

Tujuan penelitian ini untuk mendapatkan informasi tentang nilai penting, simpanan karbon vegetasi dan estimasi nilai ekonomi simpanan karbon mangrove di Kecamatan Kema, Kabupaten Minahasa Utara, Sulawesi Utara. Pengambilan data dilakukan di tujuh stasiun dengan menggunakan metode transek kuadrat 100 m2 yang diletakkan secara vertikal terhadap garis pantai. Identifikasi spesies mangrove berdasarkan ciri-ciri morfologi akar, daun, buah dan bunga. Pengukuran DBH untuk mengetahui biomassa dan simpanan karbon sedangkan estimasi nilai ekonomi simpanan karbon menggunakan pendekatan harga dari pasar bebas dan pasar wajib Clean Development Mechanism (CDM). Sebanyak delapan species teridentifikasi yaitu Avicennia alba, Avicennia officinalis, Bruguiera gymnorhiza, Ceriops tagal, Lumnitzera littorea, Rhizophora apiculata, Rhizophora mucronata dan Sonneratia alba. Spesies R. mucronata teridentifikasi di semua stasiun. Hasil analisa struktur komunitas terlihat bahwa spesies R. mucronata dan S. alba memiliki tingkat kerapatan relatif spesies yang lebih tinggi dibandingkan spesies yang lain. Penutupan relatif spesies (Rci) menunjukkan bahwa S. alba mendominasi spesies yang lain sebesar 62% dan R. mucronata sebesar 26,34%. Analisa INP menunjukkan S. alba dan R. mucronata memiliki peran yang penting dalam keberlangsungan ekosistem ini. Nilai rata-rata simpanan karbon di kawasan Kema sebesar 133,76±25,70 MgCha-1. Nilai rerata estimasi ekonomi simpanan karbon yang dihasilkan adalah sebesar Rp. 6.955.123.566 (pasar bebas) atau US$ 519.310,56 dan Rp. 18.176.056.252 (CDM) atau US$ 1.357.131,6 untuk simpanan rerata karbon sebesar 23.397±4.495 MgC (85.865,72±16.496,15 Mg CO2e) pada luasan mangrove sebesar 174,92 ha. Nilai ekologis dan ekonomis yang dihasilkan dari penelitian ini, dapat dijadikan sebagai informasi awal perumusan kebijakan pengelolaan ekosistem mangrove yang lestari dan berkelanjutan.

Teluk Banten di utara kota Serang, Banten, menampung berbagai muatan sedimen dari 7 (tujuh) sungai yang bermuara di teluk ini. Penelitian yang dilakukan pada bulan Oktober 2008 di perairan teluk ini bertujuan untuk memahami karakteristik sebaran sedimen permukaan dan komposisi bahan organik serta laju sedimentasi sebagai bagian dari penelitian karbon laut di Indonesia. Metode yang dilakukan adalah metode deskriptif, dengan memeriksa sedimen yang diambil menggunakan grab sampler. Analisis sedimen meliputi pengukuran tekstur sedimen, bahan organik total atau total organic matter (TOM) dan laju sedimentasi; analisis perairan meliputi bahan organik terlarut dan total padatan tersuspensi atau total suspended solids (TSS). Dalam klasifikasi pasir, debu dan liat, sample yang dikumpulkan dari Teluk Banten menunjukkan tekstur sedimen pasir rata-rata sebesar 54,86 %, sedangkan nilai TOM dan karbon organik berkisar 5,33 – 20,57 % dan 0,47 – 3,44 %. Laju sedimentasi tercatat berkisar antara 0,011 – 0,035 kg/m2/hari dengan komposisi tertinggi pada tekstur pasir.

Pengamatan sebaran dan luas hutan mangrove di Pulau Rambut telah dilakukan pada bulan November 2017 dan Juli 2010 dengan menggunakan analisis foto udara dan citra Geo Eye 1. Kunjungan lapang dilakukan untuk validasi lapang. Metode yang digunakan dalam penelitian ini adalah segementasi dan klasifikasi terbimbing menggunakan metode analisis berbasis objek (OBIA). Hasil analisis foto udara, data citra dan validasi data pengamatan lapangan, diestimasi bahwa sebaran dan luas hutan mangrove di Pulau Rambut adalah 16,73 ha untuk tahun 2010 dan 17,48 ha di tahun 2017 atau terjadi penambahan sebesar 0,75 ha. Mangrove di P. Rambut terdapat 10 jenis dan didominasi oleh rhizophora mucronata (Onrizal dan Kusmana, 2006). Hasil penelitian menunjukkan bahwa analisis dijital berbasis objek terhadap foto udara hasil akuisisi menggunakan drone memberikan hasil yang lebih baik untuk pemetaan dinamika hutan mangrove jika dibandingkan dengan penggunaan citra satelit GeoEye 1, dengan akurasi keseluruhan sebesar 77,3% dan nilai koefisien kappa sebesar 0,62.

Ekosistem mangrove memiliki kemampuan untuk menyerap dan menyimpan karbon. Beberapa penelitian memperlihatkan besarnya kemampuan penyerapan dan penyimpanan karbon oleh ekosistem ini. Namun demikian, kapasitas penyimpanan ini akan menurun karena deforestrasi dan konversi lahan. Tujuan penelitian ini adalah menganalisa dampak alih fungsi lahan mangrove terhadap sifat sedimen serta kemampuannya dalam menyimpan karbon. Penelitian dilakukan di empat lokasi yaitu di Kabupaten Berau - Kalimantan Timur dan Karimunjawa-Jawa Tengah yang mewakili daerah alami serta, Kabupaten Pati - Jawa Tengah dan Kabupaten Indramayu – Jawa Barat yang mewakili mangrove yang pernah mengalami alih fungsi lahan dan telah direhabilitasi. Sedimen diambil minimal sampai pada kedalaman satu meter dengan menggunakan soil auger. Sebanyak empat sampel diambil pada setiap core sediment pada interval kedalaman 0-15, 15-30, 30-50 dan 50-100 cm. Mangrove yang pernah mengalami alih fungsi lahan memiliki nilai bulk density yang lebih tinggi serta konsentrasi CN (%) dan simpanan karbon (MgCha-1) yang lebih rendah dibandingkan dengan lokasi yang alami. Hasil penelitian ini menunjukkan bahwa alih fungsi lahan mangrove menurunkan kemampuan penyimpanan karbon ekosistem dan diperlukan waktu untuk meningkatkan nilai simpanan karbon sedimen pada daerah yang pernah mengalami alih fungsi.

ABSTRAK Penelitian ini dilakukan untuk mengetahui karakteristik dan potensi perairan Teluk Buyat dan Teluk Ratatotok guna mendukung potensi sumberdaya hayati ekosistem laut dan pesisir, khususnya ekosistem lamun. Penelitian dilakukan pada Juni 2013 pada 6 stasiun di Teluk Buyat dan 4 stasiun di Teluk Ratatotok. Parameter yang diukur in-situ dengan menggunakan alat water quality meter adalah pH, salinitas dan suhu. Parameter nitrat, fosfat dan klorofil-a dianalisis dengan menggunakan metode APHA. Data tutupan lamun diperoleh dengan metode transek kuadrat sesuai Seagrass Watch Method. Hasil pengamatan dipetakan secara spasial menggunakan Ocean Data View. Analisis hubungan antara parameter perairan dan tutupan lamun mengunakan Principal Component Analisis. Hasil penelitian menunjukkan bahwa suhu, salinitas dan klorofil-a pada perairan berperan penting pada tutupan lamun dan secara umum kondisi perairan Teluk Buyat dan Teluk Ratatotok masih dalam kategori baik dan subur serta layak untuk kehidupan biota laut, khususnya ekosistem lamun. ABSTRACT The aim of this research is to identify the characteristics and potential of Buyat Bay and Ratatotok Bay waters to support natural resources in marine and coastal ecosystems, especially seagrass ecosystem. The research was conducted in June 2013, at 6 stations in Buyat Bay and 4 stations in Ratatotok Bay. The in-situ parameters measured using water quality meter instrument were pH, salinity and temperature. Water sample for nitrate, phosphate and chlorophyll-a concentration were taken to laboratory used APHA method. Seagrass cover data obtained with the square method transect of Seagrass Watch. The observations were mapped spatially using Ocean Data View software. Principal Component Analysis was used to analyse the relationship between the water parameters and seagrass covers. The result shows that temperature, salinity and chlorophyll-a at Buyat and Ratatotok Bay waters are considerably good to support the living of marine biota, especially seagrass ecosystem.

ABSTRAK Provinsi Sulawesi Utara memiliki memiliki letak strategis di mana berada di jalur pelayaran kawasan pasifik serta kawasan segitiga terumbu karang dunia. Berbagai penelitian kelautan telah dilakukan di kawasan ini, namun demikian belum ada informasi ilmiah tentang karbon laut yang sangat penting untuk memahami dinamika fluks karbon dalam kerangka mitigasi perubahan iklim. Tujuan dari penelitian ini untuk menyediakan informasi awal mengenai sebaran karbon di perairan Sulawesi Utara dan menganalisis potensi penyerapan dan pelepasan karbon dioksida (CO2) di beberapa perairan Sulawesi Utara. Pengukuran dilakukan secara langsung di lapangan pada parameter pCO2. Pengukuran pCO2 dilakukan di perairan Teluk Buyat, Teluk Totok, Teluk Manado, Selat Lembeh dan perairan Tongkaina. Data-data pCO2 hasil pengukuran di perairan Teluk Buyat berkisar 414,17 – 608,29 µatm, perairan Teluk Ratatotok berkisar 428,18 – 516,97 µatm, perairan Teluk Manado berkisar 385,16 – 395,52 µatm, perairan Selat Lembeh berkisar 342,90 – 492,12 µatm dan perairan Tongkaina berkisar 394,54 – 568,32 µatm. Nilai pCO2 terendah terletak di perairan teluk Manado sedangkan yang tertinggi terletak di perairan Teluk Buyat. Kisaran hasil pengukuran masih dalam batas normal pengukuran di daerah pesisir yang berkisar antara 200 – 4.600 μatm. Hasil analisis ∆pCO2 Teluk Buyat, Teluk Totok, perairan Tongkaina dan perairan Selat Lembeh berperan sebagai pelepas karbon dan untuk Teluk Manado berperan sebagai penyerap karbon. ABSTRACT North Sulawesi has strategically located in the shipping lanes of the Pacific region as well as in the Coral Reef Triangle. Various marine researches have been done in the area, however, there is no scientific information about the ocean carbon which is essential to understand the dynamics of carbon flux in terms of climate change mitigation. The purpose of this study is to provide preliminary scientific information on the distribution of carbon and to analyze the sink and source potency in North Sulawesi waters. In situ measurements performed on the parameter pCO2. Measurements of pCO2were taken in the waters of Buyat Bay, Totok Bay, Manado Bay, Lembeh Strait and Tongkaina waters. In the waters of Buyat Bay ranged from 414.17 to 608.29 μatm, Ratatotok Bay ranged from 428.18 to 516.97 μatm, Manado Bay waters ranged from 385.16 to 395.52 μatm, Lembeh Strait waters ranged from 342.90 to 492,12 μatm and Tongkaina waters ranged from 394.54 to 568.32 μatm. Lowest pCO2 values located in Manado Bay, while the highest in Buyat Bay. Range measurement results are within normal limits measurements in coastal areas ranging from 200 – 4.600 μatm. The result of ∆pCO2analysis shows that Buyat Bay, Totok Bay, Tongkaina waters and Lembeh Strait relatively act as carbon source and Manado Bay as carbon sink.

ABSTRAK Penelitian ini bertujuan untuk mengetahui kondisi terumbu karang pasca tsunami sebagai langkah awal dalam upaya rehabilitasi terumbu karang. Metode yang digunakan adalah dengan membandingkan kondisi terumbu karang tahun 2002 sebelum tsunami dan tahun 2009 pasca tsunami menggunakan citra satelit Landsat ETM7 melalui analisis Lyzenga. Pengamatan langsung di lapangan menggunakan metode LIT (Line Intercept Transect) dan pengukuran kualitas perairan. Lokasi pengamatan berada di Ujung Seurawan, Sea Garden di Pulau Rubiah, Sea Garden 1, Rubiah Channel 2 dan Loh Weng. Kondisi terumbu karang yang berada di Taman Wisata Alam (TWA) Pulau Weh ini berada pada kondisi yang buruk sampai baik. Terumbu karang kondisi baik terdapat di lokasi Sea Garden 1 (54,26 %), kondisi sedang di Rubiah Channel 2 (26,32%) dan Sea Garden 2 (39,5%) sedangkan kondisi buruk terdapat di Ujung Seurawan (19,28 %) dan Loh Weng (15,14%). Bentuk kerusakan terumbu karang antara lain patah, terbalik dan hanyut. Jenis terumbu karang yang rusak terdapat di sebelah timur Pulau Weh yaitu sekitar Pulau Rubiah dan sekitar Teluk Loh Pria Laot. Kisaran kondisi perairan berupa pH, salinitas, suhu dan DO menunjukkan bahwa kualitas perairan berada pada kondisi baik untuk perencanaan kegiatan rehabilitasi terumbu karang. ABSTRACT This study aims to determine the condition of coral reefs after the tsunami as the first step in the rehabilitation of coral reefs. The methods used are of comparing the condition of coral reefs between pre-tsunami in 2002 and post-tsunami in 2009 using Landsat satellite imagery ETM7 through Lyzenga analysis, direct observe of the coral reefs in the field have been done using the LIT (Line Intercept Transect) and measurement of water quality. Locations of observations are in Ujung Seurawan, Sea Garden in Rubiah Island, Sea Garden 1, Rubiah Channel 2 and Loh Weng. The condition of coral reefs in the Natural Park (TWA) Weh Island is generally in the range between poor and good. The coral reefs at Sea Garden 1 (54.26 % ) are in good condition, those in Rubiah Channel 2 (26.32 % ) and Sea Garden 2 (39.5 %) are in moderate condition, while those in Ujung Seurawan (19.28 % ) and Loh Weng (15.14 %) are in poor conditions. Forms of damage to coral reefs are including broken, overturned and swept away. The damaged reefs are located on the east of Weh Island, which is around Rubiah Island and around the Gulf of Loh Pria Laot. Range of water conditions such as pH, salinity, temperature and DO indicate that the qualities of the waters are good for rehabilitation planning of coral reefs.

Perairan Indonesia merupakan zona kritikal chokepoint untuk pengukuran arus laut bagi pemahaman ariabilitas iklim. Diketahui bahwa ada perbedaan elevasi muka air laut rerata antara kawasan Samudra Pasifik sebelah barat dengan Samudra Hindia bagian Timurlaut (Northeast Indian Ocean), yang menyebabkan terjadinya aliran massa air yang berasal dari Samudra Pasifik menuju Samudra Hindia melewati perairan Indonesia, yang dikenal sebagai Arus Lintas Indonesia (ARLINDO). Pada saat terjadi El Nino, dimana elevasi muka air rerata di bagian barat Samudra Pasifik turun, maka ARLlNDO ini akan melemah. Dengan demikian dapat diperoleh identifikasi bahwa jika ARLlNDO mulai melemah maka akan terjadi El Nino. Dimana makin besar angkutan massa air oleh Arlindo maka akan memperlambat siklus El Nino. Sebagaimana diketahui bahwa El Nino dan La Nina memberi dampak besar bagi terjadinya anomali iklim Indonesia dan global, misalnya kemarau yang berkepanjangan atau curah hujan yang menimbulkan banjir bandang. Fenomena tersebut sangat menarik untuk menjadi bahan kajian bagi para peneliti oseanografi dunia maupun Indonesia. Dalam rangka itu maka dibuatlah kesepakatan bersama antara Indonesia, Amerika Serikat, Australia, Belanda dan Perancis yang ditandatangani pada 12 Desember 2002 di Scripps Institution of Oceanography, Amerika untuk melakukan Ekspedisi INSTANT (International Nusantara STratification ANd Transport) pada tahun 2003 2007. Aktifitas yang dilakukan adalah Deployment Cruise yaitu memasang berapa mooring, Rotation Cruise (mengangkat dan memasang kembali mooring) dan Recovery Cruise (mengangkat mooring) di Selat Makassar, Pintasan Lifamatola (Lifamatola Passage), Selat Lombok, Selat Ombai, dan di Pintasan Timor (Timor Passage). Dalam buku ini akan dipaparkan berbagai aktifitas dalam Program INSTANT tersebut antara lain deskripsi pemasangan mooring di lima lokasi, konfigurasi peralatan mooring, wahananya dan pelaksanaannya mulai dari pemasangan sampai dengan pengambilan dan pengolahan data.