Indonesia Conference Directory

Corresponding Author
Suliskania Nurfitri

Institutions
1) Institute of Oceanography, University of Hamburg, Bundesstrasse 53, D-20146 Hamburg, Germany
2) Department of Oceanography, Institut Teknologi Bandung, Jalan Ganesha 10, Bandung 40132, Indonesia
3) Center for Deep-Sea Research, Indonesian Institute of Science, Jalan Y. Syaranamual Guru-Guru Poka, Ambon 97233, Indonesia

Abstract
The Arafura Sea is a relatively shallow water basin (less than 200 m) which is subjected to monsoonal winds and affected by the Banda Sea circulation. During the southeast monsoon (May to September) there is evidence of upwelling in this region which is indicated by the cooler SST (Sea Surface Temperature) and elevated chlorophyll concentration, especially at the coast of Papua (northern Arafura Sea). In order to address the origin of the upwelled waters masses, a numerical study using Lagrangian particles was utilized. The model was run backward in time to trace the trajectory of the particles arriving at the northern Arafura Sea, particularly in the upper 50 meters. Each particle was traced backward for three months with the arrival date August 31, 2014, as it is representative for an upwelling month. By this experiment we can identify the origin of the particles on June 1, including their depth, which arrive in the northern Arafura Sea. The daily velocity fields of the 3-D model HAMSOM (HAMburg Shelf Ocean Model) application to the Banda and Arafura Sea for 2014 were used to force the Lagrangian particle-tracking experiment. In general, 76.5% (62.3%) of particles arriving in 2.5 m (22.5 m) depth, originated from the upper 50 m of the Ceram and Banda Sea. In addition, particles originating from the depth interval 50-100 m contribute 19.6% (26.8%) to the number of particles arriving in 2.5 m (22.5 m) depth. On the other hand, for particles arriving in 47.5 meter depth 46% are originating from the upper 50 m of the southeastern Arafura Sea and 43% from a depth below 100 m of the eastern Banda Sea.

Keywords
Arafura Sea; Upwelling; Lagrangian study; Backward trajectory

Topic
Coastal and Ocean Dynamics

Link: https://ifory.id/abstract/upLaCNK4bRdM

Corresponding Author
Ahmad Sirojudin Munir

Institutions
a) Physics Department, Faculty of Mathematics and Natural Sciences, Mulawarman University
Jl. Barong Tongkok, Gn. Kelua, Samarinda Ulu, Samarinda, East Borneo, 75242, Indonesia
*avatarraz[at]gmail.com
b) Mathematics Department, Faculty of Mathematics and Natural Sciences, Mulawarman University
Jl. Barong Tongkok, Gn. Kelua, Samarinda Ulu, Samarinda, East Borneo, 75242, Indonesia

Abstract
In the Makassar Strait, upwelling occurred by wind-driven current and complexity of bottom topography. Analysis of upwelling phenomena could be determined by salinity, temperature dan three-dimensional current value which happened on a year as a climatology change. Regional Ocean Modelling System (ROMS) is a terrain following three-dimensional model to calculate numerical value which need stability for long-duration simulation. The model has been simulated for 1 years from 1 January 2017 to 31 December 2017 and verified by tidal data. Horizontal Boundary Condition which contain u-v velocities, salinity and temperature, is a climatology data from GLBa0.08 HYCOM. While Vertical Boundary used as atmospheric forcing is a data from ERA-INTERIM ECMWF. The verification use RMSE and RRE methods, showed good result between model and observation data with RMSE=0.1454 meter, and RRE=6.5806%. The result was analysed from 12 sampling points, 6 points on the outflow of the Makassar Strait which generated upwelling and the 6 others on the canal that connect to the Flores Sea and Java Sea. Model giving good result on January, indicate average w-velocity is 9.1183 m/day

Keywords
Analytical Model; Makassar Strait Outflow; Upwelling; Ocean Temperature Circulation;

Topic
Coastal and Ocean Dynamics

Link: https://ifory.id/abstract/3x2MhKgecUXa

Corresponding Author
Faruq Khadami

Institutions
1 Ocean College, Zhejiang University, Zhoushan 316021, China
2 Institut für Geowissenschaften, Christian-Albrechts Universität zu Kiel, 24118 Kiel, Germany
3 Key laboratory of submarine Geosciences, Second Institute of Oceanography, Minister of Natural Resources, Hangzhou 310012, China
4 Helmholtz Center for Ocean Research Kiel GEOMAR, Kiel 24118, Germany
5 Department of Oceanography, National Sun Yat-Sen University, Kaohsiung 804, Taiwan
*e-mail: chenxg83[at]zju.edu.cn

Abstract
Main text: The Lutao hydrothermal field is an intertidal arc-volcanic system located at offshore southeast Taiwan, hosting a Zhudanqu (ZDQ) vent and a Huwaichi (HWC) spring. The totally depleted Mg, moderately enriched chloride and H+ with respect to seawater indicated that the ZDQ endmember was solely derived from the brine phase resulted from low-degree subcritical phase separation. The vapor phase comprised the endmember for the HWC vent fluids. The temperature and pressure of the phase separation were estimated as ~ 150 oC and ~ 5 bar, respectively. The water/rock ratio was calculated as about 2. The Lutao hydrothermal system was slightly affected by semi-diurnal tides, either by tidal loading, or tidal currents, or a joint effort of both. The active circulation period of the Lutao system was about 3 h according to the time delay of its response to tides. Freshwater was almost absent in the HWC vent fluids at normal conditions. The typhoon Fung-wong that attacked the island on Sep 21st, 2014, however, imported freshwater into the vent fluids with a percentage of ~ 16%. Both the ZDQ and the HWC endmembers were a little changed after the typhoon event, suggesting a cooling of the reaction zone. Presumably, the seawater was cooled by the tropical storm by 2-5 oC which consequently quenched the reaction zone and declined the degree of phase separation. After the typhoon passing by, the hydrothermal system began to recover, evidenced by increasing percentages of the HWC endmember and decreasing freshwater contributions. The flux of the HWC endmember was estimated as ~ 500 L h-1 based on these observations. This study, for the first time, reports a shallow-depth hydrothermal system that was cooled by a tropical storm and affected by tides.

Keywords
Hydrothermal system; Tide; Typhoon;

Topic
Coastal and Ocean Dynamics

Link: https://ifory.id/abstract/HnawVTbR4FzD

Corresponding Author
Idris Mandang

Institutions
a) Department of Geophysics, Faculty of Mathematics and Natural Sciences Mulawarman University
* idris[at]fmipa.unmul.ac.id

Abstract
El Nino Southern Oscillation (ENSO) has been related to climate anomalies throughout the world including East Kalimantan-Indonesia. Extreme rainfall is one of climate anomalies that related by ENSO. This research was analysis extreme rainfall and relationship with ENSO in East Kalimantan. The data set in this research start from 1986 to 2012 but some of stations only have data set from 1993-2012 and 1999-2012. The Correlation analysis and Gumbel are methods that use in this research. Gumbel is distribution method that can be used to predicted flood and the other disaster. Two, five, ten, twenty five, fifty and one hundred years return period for extreme monthly rainfall maximum can be found using the Gumbel Method. The largest rainfall values of two years return period obtained from sta-24 (535,07 mm), five years from sta-2 (788,84 mm), ten years from sta-7 (986,84 mm), twenty five years from sta-2 (1321,65mm), fifty years from sta-2 (1570,00 mm), and one hundred years from sta-2 (1816,51 mm). For the correlation analysis, most of stations were found positive correlation between Monthly rainfall and Southern Oscillation Index. The highest of coefficient correlation is 0,4 (21,4% from all of station). The other stations have correlation coefficient 0,3 (21,4%), 0,2 (32,1%) and less than 0,2 only 21% from all of stations. The result shows that generally rainfall in East Kalimantan related by ENSO.

Keywords
Extreme Rainfall, ENSO, SOI, Gumbel Method, Correlation Analysis.

Topic
Coastal and Ocean Dynamics

Link: https://ifory.id/abstract/JAneNfvZwFj7

Corresponding Author
Zetsaona Sihotang

Institutions
a) Earth Science Department, Faculty of Earth Science and Technology, Bandung Institute of Technology
Jalan Ganesa No 10, Bandung, 40132, Indonesia
*zetsaona.sihotang[at]students.itb.ac.id
b) Hydro-Atmosphere Environment Research Group, Physical Oceanography and Computational Modeling Laboratory, Program Study of Physics, Faculty of Mathematics and Natural Sciences, Mulawarman University
Jalan Barong Tongkok No 04, Samarinda, 75123, Indonesia

Abstract
The Eastern Indonesian Waters are quite a complex area where this region is traversed by Indonesian Throughflow (ITF) that carries water masses from the Pacific Ocean to the Indian Ocean. The water mass movements have an influence on the condition of the waters in this region, which is the Sea Surface Temperature (SST). The SST has an important role that can control weather and climate. This study aims to analyze the phenomena that occur in the distribution of SST in the Halmahera and Banda Seas. The data used for this research is ten years of SST data (1995-2014) in the Halmahera and Banda Seas. The EOF (Empirical Orthogonal Function) method based on the EVP (Eigen Value Problem) applied to the SST data which produces three main components, that is EOF mode and PC mode respectively. The spatial pattern (EOF modes) shows that SST in the Halmahera and Banda Sea regions, while the temporal pattern (PC modes) shows the cycle of phenomena affecting the SST in these regions. The first mode produces 86.66% variance meaning that the monsoon cycle dominantly affecting SST distribution in the Halmahera and Banda Seas. Whereas in the second mode (6.16%) and the third mode (2.13%) indicating a local cycle and shows that the ENSO cycle has a weakly influence on the SST distribution in the study area. It is also has been clarified by the correlation value between ONI (Oceanic Nino Index) and SST is about -0.245.

Keywords
SST; Halmahera and Banda Sea; ENSO; EOF

Topic
Coastal and Ocean Dynamics

Link: https://ifory.id/abstract/dvBaKurJptyQ

Corresponding Author
Suyadi .

Institutions
Lembaga Ilmu Pengetahuan Indonesia

Abstract
Weda Bay is one of mega-biodiversity spots in Indonesia, for example it is one of the largest mangrove habitat in North Maluku. However, data and information of mangrove vegetation and its ecosystem services particularly carbon stocks are lacking. Mangroves were sampled using transects in five sites of mangroves across Weda Bay. The transects extended from seaward to landward to cover all vegetation variation. Environmental data (water and substrate) were collected using Conductivity Temperature and Depth (CTD), Dissolved Oxygen (DO) meter, and sediment core. The objective is to identify characteristics of mangrove vegetation, environment, and it ecosystem services in term of aboveground carbon stocks. The study found 17 species of mangrove and the dominant species was Rhizophora apiculata, followed by Bruguiera gymnorrhiza. The importance index of those species were high (Importance index > 45) in the four sites (Yevi, Imam, Halmahera, and Bori-Bori), but Rhizophora Stylosa was important species in Dadawe site (Importance index: 58). The density of mangrove tree was 987 stem ha-1 and sapling was 1,470 stem ha-1. Substrate of mangrove did not vary significantly with distance from the seaward which mainly dominated by mud and clay (3.9 - 63 µm). Mean water temperature in the mangrove area was 29.3℃, salinity 34.1 psu, mean water suspension was 46 mg l-1, mean dissolved oxygen was 3.2 mg l-1, and water current was 10 m s-1. Aboveground carbon stocks were considerable (mean 154 Mg C ha-1, maximum 425 Mg C ha-1). Change in aboveground carbon stocks over the distance from the seaward edge to landward edge was not significantly different. The study also observed mangrove deforestation, exploitation (fire wood), and plastic pollution in all study sites. These data indicate that the environment (water and substrate) of Weda Bay is suitable for mangroves. However, this ecosystem faced some threats such as mangrove deforestation, wood exploitation, and pollution. It can be estimate that mangrove deforestation generates emissions up to 1,546,599 Mg CO2e ha-1 or equivalent with the loss of carbon market price up to US$ 108 million ha-1. These values exclude belowground carbon stocks and other function and services of mangroves. Better mangrove management e.g. reducing deforestation and pollution are required to protect the functions and ecosystem services of mangroves.

Keywords
mangrove vegetation, mangrove environment, carbon stocks, Weda Bay

Topic
Coastal and Ocean Dynamics

Link: https://ifory.id/abstract/k3MCc9UWxN82

Corresponding Author
NUR AINI MD NOR

Institutions
¹ Centre of Studies for Surveying Science and Geomatics, UiTM Shah Alam, Malaysia
² Oceanography Study Program, Faculty of Earth Science and Technology, Institute Technology of Bandung, Indonesia

Abstract
Kuala Terengganu is one of the areas which were subjected to critical erosion in Malaysia. It is believed that human activities became one of the causes of this incident. Kuala Terengganu is location of Sultan Mahmud Airport. In January 2008, the Malaysia government approved to upgrade the airport included improvement to the terminal and runway extension. The construction is located near the coast, therefore it is necessary to monitor the coast of Kuala Terengganu. This study focuses on the shoreline change detection along the Kuala Terengganu during ten years period between 2007 until 2017 using LANDSAT Images. Digital Shoreline Analysis System (DSAS) is an extension for the ArcGis was used to identify and measure erosion (shoreline retreat) and accretion (shoreline advance) along the coast. From the analysis, the action will take better information disclosure and state government can take action to reduce the erosion. Environmental impact assessment benefits occur in many guises such as improved project design and improved decision making.

Keywords
DSAS, LANDSAT, Shoreline change, Erosion, Accretion

Topic
Coastal and Ocean Dynamics

Link: https://ifory.id/abstract/fdje6HRq3vBP

Corresponding Author
Muhammad Riza

Institutions
1) Department of Oceanography, Bandung Institute of Technology, Indonesia
2) Program Study of Physics, Faculty of Mathematic and Natural Sciences, Mulawarman University, Samarinda, Indonesia

Abstract
Variations of volume transport in the Halmahera Sea are strongly influenced by the El Nino Southern Oscillation (ENSO). Based on the ENSO Index at Nino 3.4, in 2011 La Nina event took place with a strength of -1.4, while in 2015 El Nino occurred with a strength of +2.6. This paper discusses the variation of transport volume caused by the ENSO phenomenon based on the results of the Regional Ocean Model System (ROMS). On the Halmahera Sea at a latitude of 0.3(^circ)S with a width of 67 km and a depth of up to 300 m, net volume transport always moves southward. The largest volume transport in La Nina 2011 occurred in September-October, which was -8.9 Sv. Meanwhile, in El Nino 2015 the largest volume transport occurred in July-August, which was equal to -4.9 Sv. The cross correlation coefficient between volume transport and SOI in 2011 and 2015 respectively was r = 0.55 and r = 0.61, where these results indicate a strong relationship.

Keywords
transport volume variation, Halmahera Sea, ENSO, numerical model, ROMS

Topic
Coastal and Ocean Dynamics

Link: https://ifory.id/abstract/Md3jKr9VnTNf

Corresponding Author
Alina Blume

Institutions
1. Indonesian Institute of Sciences (LIPI)-R.C for Geotechnology, 2. RWTH Aachen-Geology Department. *Corresponding author sri004[at]lipi.go.id

Abstract
Indonesia is an important site for climate studies, because of it-s located between Indian and Pacific oceans. Climate phenomena which is happened in the Pacific and Indian oceans i.e El Nino Southern Oscillation (ENSO) and Indian Ocean Dipole (IOD) influence Indonesian climate. To understand behaviour of climate phenomena and its impact to Indonesian climate it is required paleoclimate data which provide long time series climate data back to hundred till thousands year. Sea surface temperature is one of important climate parameter. Coral Sr/Ca is convinced as coral paleo-thermometer. In this study, the available coral Sr/Ca is used to reconstruct past SST variability (Coral SST). The variability of coral SST from several sites in Indonesia waters is investigated and compared between sites. The coral SST is also correlated with the Nino 3.4 and IOD indices to know how the climate phenomena influence the SST variability. The result shows that the influence of IOD and ENSO difference between sites. Some sites e.g Seribu island coral SST shows that SST is influenced by IOD rather than ENSO, while from Timor coral SST shows that shows that Indian Ocean Dipole (IOD) influences SST and SSS while ENSO only influences SST

Keywords
Sr/Ca, coral, SST

Topic
Coastal and Ocean Dynamics

Link: https://ifory.id/abstract/A7MzTr4cVJXn

Corresponding Author
Faisal Hamzah

Institutions
1Institute for Marine Research and Observation, Ministry of Marine Affairs and Fisheries, Bali, 82251 Indonesia. (faisalhamzah[at]kkp.go.id)
2State Key Laboratory of Marine Environmental Science, College of Ocean and Earth Science, Xiamen University, Xiamen, 361102, China
3First Institute of Oceanography, State Oceanic Administration, Qingdao 266061, China
4Laboratory for Regional Oceanography and Numerical Modeling, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266237, China
5Key Laboratory of Ocean Circulation and Waves, Institute of Oceanology, Chinese Academy of Sciences
6Qingdao National Laboratory for Marine Science and Technology, and Center for Ocean Mega-Science, Chinese Academy of Sciences, Qingdao, and University of Chinese Academy of Sciences, Beijing, China
7Research Center for Oceanography, Indonesian Institute of Sciences, Jakarta, Indonesia

Abstract
Research on the carbonate system in the tropical regime of the Indonesian Seas is limited and required to understand carbonate dynamics due to the Indonesian throughflow (ITF). Here, we present marine carbonate system along the main routes of the ITF spanned Mindanao-Sulawesi, Sulawesi Sea, Makassar Strait and Lombok Strait during strong 2015 El Niño and transition seasons of October 2017. Along the main routes, dissolved inorganic carbon (DIC) and total alkalinity (TAlk) were shown lower compared to the main outflow passage of the Lombok Strait. Physical and biogeochemical processes in the upper thermocline is dominated by photosynthesis and carbon dioxide (CO2) release to the atmosphere induced by vertical mixing. DIC vs. TAlk relationship shown mixing process occurred in the upper thermocline following the stratified North Pacific waters. In the upper 150 m, freshwater contribution changed the ITF water structures particularly after the Labbani channel to the Lombok Strait. Strong seasonal and spatial variabilities of sea-air exchange along the main routes. The difference between sea and air partial CO2 (ΔpCO2) in the Mindanao-Sulawesi to eastern Sulawesi Sea showed the main inflow act as sink with a slightly source of atmospheric CO2 ranged from -7 to 23 μatm (-0.19-0.72 mmol C m-2 d-1), while the Makassar strait (3.4-128 μatm) and along southern Makassar Strait to the Lombok Strait (51-76 μatm) were act a source within CO2 degassing of 0.09-8.3 and 2.2-6.9 mmol C m-2 d-1, respectively. Estimating potential carbon flux to support the Indian Ocean primary productivity from the Makassar Strait was ~9972 Tg C y-1 whereas 2090 Tg C y-1 exports to the Indian Ocean via the Lombok Strait, while the remained carbon of 7881 Tg C y-1 were transported to the Banda Sea.

Keywords
carbonate system, Indonesian Sea, Indonesian Throughflow

Topic
Coastal and Ocean Dynamics

Link: https://ifory.id/abstract/utG8yzCEPnX6

Corresponding Author
Hasti Amrih Rejeki

Institutions
School of Meteorology Climatology and Geophysics, The Agency for Meteorology Climatology and Geophysics of Republic of Indonesia
Jalan Perhubungan I No. 5, Komplek BMKG, Tangerang Selatan 15221, Indonesia
*hastiamrihrejeki[at]gmail.com

Abstract
The Indonesian Maritime Continent is an area of propagation and crossing of Madden Julian Oscillation (MJO) in phases 3, 4, and 5. The active MJO causes the increasing of convective activity and strong winds on the area it passed. In the active phase, the ocean will get a response from MJO activities as the response to strong westerly winds. The depth of the thermocline in the tropics varies from season to season and from year to year. MJO, as the intraseasonal variability is one of the causes for the variations in the depth of the thermocline layer. The objectives of this study are to investigate and properly understanding the equatorial thermocline dynamics related to MJO activity in the Indonesian Maritime Continent. By using the temperature data in 0 - 400 m of depth which obtained from Marine Copernicus, this study will investigate the equatorial thermocline dynamics which are precisely at 5N, 0, and 5S of latitude in the MJO phase 3, 4, and 5 area during the period of 2018. The results showed that the dynamics of the thermocline depth has a response to MJO according to the location of the activity. However, it also decreases the thermocline depth in the northern (southern) equator. The results of this study also show the relation of convective activity in the atmosphere with variations in thermocline depth which will also have an impact on weather conditions in the Indonesian region.

Keywords
Indonesian Maritime Continent; Madden Julian Oscillation; Equatorial Thermocline Dynamics

Topic
Coastal and Ocean Dynamics

Link: https://ifory.id/abstract/DXLh4RuBgaUm

Corresponding Author
Selfrida Missmar Horhoruw

Institutions
(a) Center of Excellence on Resource Conservation of Tuna,

(b) Research Center for Deep Sea-Indonesian Institute of Sciences (LIPI)

(c) Department of Marine Science and Technology, Bogor University

Abstract
Banda Sea waters is the potential area for fisheries, especially for Tuna. Banda eddy and the relationship to chlorophyll-a were studied using the output of ocean circulation model INDESO (Infrastructure Development of Space Oceanography) configuration from 2008-2011 during normal (June-August 2008) and ENSO (El Nino/ June- August 2009 and La Nina/ June-August 2010). The model result showing two clockwise eddies in the northern part of Banda sea and three counterclockwise eddies in the southern part of Banda Sea. The eddy counterclockwise was found from 20 m depth and causing upwelling along the island arc on the western edge of Banda sea. Eddy counterclockwise in the southern of Banda Sea cause the downwelling. The presence of these 5 eddies is thought to be an important factoring in maintaining water balance system in the Banda Sea as long as southeast monsoon period. In the surface, higher vorticity of the eddy was found in the northern of southwest Maluku Island. The presence of this eddy is thought to have a strong influence on nutrient loss on the surface. Our research shows that during the La Nina period, the eddies vorticity increased causing low surface chlorophyll in the surface the Banda Sea.

Keywords
Banda Eddy, ENSO, chlorophyll-a, upwelling, downwelling, INDESO

Topic
Coastal and Ocean Dynamics

Link: https://ifory.id/abstract/Ehc3ALuWv7XH

Corresponding Author
Ejria Saleh

Institutions
Borneo Marine Research Institute, Universiti Malaysia Sabah, Jalan UMS, 88400 Kota Kinabalu, Sabah, MALAYSIA;

Abstract
Semporna is one of the most significant areas in the Malaysian Coral Triangle. This area is known as Semporna Priority Conservation Area (SPCA) and the first Marine Spatial Plan in Malaysia. The shallow water areas within its islands are identified for mariculture activities, fishing sites and tourists destination. One part of the area is Tando Bulong Strait located between Semporna and Bum Bum Island. The excellent natural environment and high marine biodiversity are related to water circulation. The objectives of this study are to determine water current pattern and wave impacts along the strait using numerical modeling. Field surveys of bathymetry, deployment of two Acoustic Doppler Current Profilers (ADCP) for water level and current measurements were done from 1 to 30 August 2017. During this field trip, assessment of current coastal community activities along the strait was also carried out. The field data (water current and water level) were needed for validation and verification of the Delft3D modelling software. The waves, current speed, and direction were analysed and presented on different tidal cycles and seasonal monsoon. Results indicate that tidal cycles and seasonal monsoon play a major role in water exchange of the Strait. The current speed along the coastline is about 0.3 m/s but increase up to 0.37 m/s along the Strait. The model predicted that flood tide current speed during the northeast monsoon flows southwards and increase between 0.6 m/s and 1 m/s at the middle of the Strait south. The wave height during this monsoon is approximately 0.65 m in the north and decreases down to 0.3 m inside the strait. The water circulation is important for the mariculture (seaweed farming), fish cages and marine pollution management. The findings will hopefully lead to a better understanding of the dynamic of the Tando Bulong Strait and improve the future prediction state of the Semporna area.

Keywords
Current pattern, waves, monsoon, Tando Bulong Strait, Semporna

Topic
Coastal and Ocean Dynamics

Link: https://ifory.id/abstract/U8hk7eZragYL

Corresponding Author
Erlin Beliyana

Institutions
a) Oceanography Student, Bandung Institute of Technology Jalan Ganesha 10, Bandung 40132, Indonesia
Graduate Program in Earth Science, Bandung Institute of Technology Jalan Ganeca 10, Bandung 40132, Indonesia
b) Oceanography Research Group, Faculty of Earth Science and Technology, Bandung Institute of Technology Jalan Ganesha 10, Bandung 40132, Indonesia
c) Department of Atmospheric and Ocean, University of Maryland, USA

Abstract
Indonesian seas are strongly affected by strong semidiurnal tidal signals from the Indian Ocean and diurnal signals from the Pacific Ocean. Therefore, within the internal seas, there is possibility of mixed tides (semidiurnal and diurnal signals). This research is focused on determining tidal current based on the velocity data measured during the INSTANT (International Nusantara Stratification and Transport) program. The velocity data from Ombai Strait and Timor Passage from January 18, 2004 to December 31, 2004 are analyzed. Characteristics of tidal current data at certain fixed depths (50, 100, 350 and 750 meters) are processed and calculated using MATLAB software and present the magnitude and variability of total currents, residual currents, and tidal currents as well as vertical variability at these straits. In Ombai Strait and Timor Passage currents tend to move zonally (east – west). The dominant tidal currents are observed at 350 and 750 meters, while subtidal (nontidal) current dominant occurs with 50 to 150 meters.

Keywords
Currents; Tidal Currents; Residual Currents; Ombai Strait; Timor Passage

Topic
Coastal and Ocean Dynamics

Link: https://ifory.id/abstract/DWv7AbxjE39J

Corresponding Author
NUR SYAHIRAH HASHIM

Institutions
¹ Centre of Studies for Surveying Science and Geomatics, UiTM Shah Alam, Malaysia
² Geodesy and Geomatics Engineering Study Program, Faculty of Earth Science and Technology, Institute Technology of Bandung, Indonesia

Abstract
A hydrographic survey can be a cumbersome sometimes. The data can be sparse, providing it can be costly and it took a lot of manpower and time. Space-borne data like multispectral images can be a helpful tool towards hydrographic survey, especially in the shallow water area. The company like EOMAP and TCARTA make use of satellite-derived bathymetry as a tool and product. Would it be great if it also can be applied in Malaysia especially on the low-risk job or survey planning. Enlarging the survey area and providing a continuous and detailed water depth information is the main objective in this research. In order to complement with convenience and cost reduction, the author used Landsat 8 "(free downloadable images)" in this research. Structuring the procedure is the main part of the process involving pre-processing and processing step until the final product obtained. In this research, the author used various kind of bathymetry algorithms such as Single-Band Algorithm, Green-Band Algorithm, and Stumpf, and the author also uses Principal Component Analysis tool from ArcMap and Spear Relative Water Depth: Log-Ratio Transform tool from ENVI to derived bathymetry. All of this bathymetry algorithm/tool gives out different technique with different statistical approach. The final result then will be compared and evaluated with Single-Beam Echosounder data (ground truth).

Keywords
Hydrography Survey, Shallow Water Area, Satellite-Derived Bathymetry, Bathymetry Mapping

Topic
Coastal and Ocean Dynamics

Link: https://ifory.id/abstract/T6E2jndpxkfJ

Corresponding Author
Wingking Era Rintaka Siwi

Institutions
Institute for Marine Research and Observation, Ministry Marine Affair and Fisheries

Abstract
Bali strait get the influence of upwelling from the Indian ocean, especially when southeast monsoon (SEM). In normal years, upwelling processes in southern Java include Bali Strait appear when entering SEM in early June to mid-October, with cold SST. Climatic variability, the incidence of India Ocean dipole (IOD) is independent of ENSO. IOD correlates strongly with seasonal conditions. Medden Julian Ossilation (MJO) can affect the ENSO cyrcle even though it is not in the context of the cause Niño or La Niña formation, but can contribute to the speed of development and intensity of El Nino and La Niña. This study aims to investigate of ENSO, IOD and MJO toward the vertical temperature in Bali Strait during SEM (August 2013 & August 2017). The location of the study in Bali Strait 8.20S - 8.80S and 114.40E-115.20E. The method used is observation in August 2013 and 2017. The information about ENSO, this study is complemented by the Ocean Nino Index (ONI) climate index data and MJO obtained from NOAAs Climate Prediction Center. The information on IOD events is positive or negative mode, DMI data is also used from JAMSTEC. Information on the incidence of ENSO and IOD was used to further analyze the influence of these climatic conditions on the evolution of vertical temperature profiles in the Bali Strait. Seasonal vertical profile temperature variability linked to climate index in Bali Strait waters is processed and analyzed using ferret software from PMEL-NOAA, ODV, and General Mapping Tools (GMT). Based on the results vertical temperature in the August 2013 were relatively cooler with a thicker mixer layer than the August 2017. In the period of August 2013, the normal ENSO conditions (-0.3) with IOD (+) (0.1) with weakening intensity, while there was a period of August 2017 normal ENSO conditions (-0.16) with strong (+) IOD (0.6). Direct linier correlation among ENSO and IOD. MJO in August 2017 looks strong than August 2013 although at the same ENSO phase (neutral). Indirect linier correlation among ENSO and MJO.

Keywords
vertival temperature, ENSO, IOD, MJO, Bali Strait

Topic
Coastal and Ocean Dynamics

Link: https://ifory.id/abstract/uWN4KBjyMqpQ

Corresponding Author
LH Wiryanto

Institutions
Department of Mathematics, Bandung Institute of Technology

Abstract
Two-fluid system of finite depth is considered in this talk. The fluids have different density and the height is also possible different. The interface between them is presented as the lower fluid height measured from the bottom. Because of a disturbance, that height changes at any time and position, so that it presents interfacial wave with KdV equation as the model. The wave propagation and deformation are observed for same various values of the physical parameters, such as density and height of the fluids. A finite difference method is shown successfully in performing the wave propagation. When the density and the height of the upper fluid tend to zero, the result confirms to the surface wave.

Keywords
KdV equation, interfacial wave, finite difference method

Topic
Coastal and Ocean Dynamics

Link: https://ifory.id/abstract/MZpUzHrj9aFu

Corresponding Author
Fareza Sasongko Yuwono

Institutions
a) Research Center for Deep Sea, Indonesian Institute of Sciences
Jalan Y. Syaranamual, Guru-Guru, Poka, Ambon 97233, Indonesia
*fare001[at]lipi.go.id
b) Faculty of International Resource Sciences, Akita University
1-1 Tegatagakuen-machi, Akita 010-8502, Japan

Abstract
Calcareous nannofossil records in the sediments from ODP Hole 806B located in Ontong Java Plateau comprising Reticulofenestra size variations, Discoaster relative abundance and nannofossil accumulation rates have been analyzed to reconstruct surface water dynamics in the western equatorial Pacific throughout the Miocene. From early to middle Miocene (18 – 14.4 Ma), the surface water was relatively warm and depleted in nutrient associated with warm condition during the Middle Miocene climatic optimum. From middle to late Miocene (14.4 – 8.8 Ma), the thermocline deepened as the western Pacific warm pool established. During the late Miocene (8.8 – 5.6 Ma), the surface water suddenly shifted into cooler and nutrient rich condition associated with enhanced equatorial upwelling. The timing of this event is coincided with the intensification of Asian monsoon.

Keywords
Miocene, sea surface, Western Equatorial Pacific, Calcareous Nannofossil

Topic
Coastal and Ocean Dynamics

Link: https://ifory.id/abstract/DrHdYaEZhMjz

Corresponding Author
Didit Adytia

Institutions
a*) School of Computing, Telkom University, Bandung, 40257, Indonesia
*adytia[at]telkomuniversity.ac.id

&

b) Industrial & Financial Mathematics Research Group,
Faculty of Mathematics & Natural Sciences,
Institut Teknologi Bandung, Bandung, 40132, Indonesia

Abstract
Modelling of wave transformation above fringing reefs are usually quite challenging. The fringing reefs are usually characterized by very steep bottom slope, so that waves that propagate above this type of bottom are usually break. To simulate the wave propagation above fringing reefs, the wave model and its numerical implementation should able to describe shoaling, breaking, nonlinear wave-wave interactions as well as dispersion accurately. In this paper, we use a Boussinesq type of model to simulate the wave transformation above fringing reefs. The wave model is implemented numerically by using finite volume method with momentum conservative staggered grid. The model is called Staggered grid Variational Boussinesq (SVB). Results of numerical implementation is validated with experimental data from hydrodynamic laboratory. Various scenarios are investigated to study effects of fringing reefs in reducing wave height.

Keywords
fringing reefs; Staggered grid Variational boussinesq model; Finite Volume.

Topic
Coastal and Ocean Dynamics

Link: https://ifory.id/abstract/pYbjtf4KAH6L

Corresponding Author
Ashadi Arifin Nur

Institutions
a) Faculty of Earth Science and Technology, Bandung Institute of Technology
Jalan Ganesa No 10, Bandung, 40132, Indonesia
*ashadi_arifin_nur[at]students.itb.ac.id
b)Hydro-Atmosphere Environment Research Group, Physical Oceanography and
Computational Modeling Laboratory, Program Study of Physics,
Faculty of Mathematics and Natural Sciences, Mulawarman University
Jalan Barong Tongkok No 04, Samarinda, 75123, Indonesia

Abstract
The coastal area in Balikpapan Bay and its surrounding area has been devastated after the burst of an underwater oil pipe at the bay on March 31st, 2018, and the crude oil still continues spreading for a few days later. A three-dimensional hydrodynamic model is used to simulate the currents dynamic and investigate the influence of the currents circulation on the spreading of the oil spill in Balikpapan Bay from March 31th to April 15th, 2018, to cover the event i.e. several weeks after the oil spill incident. Model results are validated by calculating the RMSE, MAPE and model skill using water level between available observation data at Semayang Port, Balikpapan station and numerical model from October 1st, 2012 to January 1st, 2013. Verification result of tidal elevation data from observation and model prediction shows a good agreement with RMSE = 7.8 cm, MAPE = 14.3% and model skill = 0.995. Surface currents circulation in Balikpapan Bay can be distinguished by the currents pattern on the spring tide and neap tide condition. During the spring tide condition, the surface currents mostly move to the east after coming out from the bay. However, the surface currents are strongly going southward after come out from the bay on the neap tide condition. Based on the satellite images captured for the next days after the event, the spreading pattern of the oil spill seems to be matched to the pattern of surface currents circulation on the spring tide condition. From the analysis of the model result, it shows that the currents circulation playing the main role to disperse the oil spill in Balikpapan Bay towards the Makassar Strait.

Keywords
Tidal current; Hydrodynamic model; Balikpapan Bay; Oil spill

Topic
Coastal and Ocean Dynamics

Link: https://ifory.id/abstract/LbzNAFEYuCwW

Corresponding Author
Marsya Jaqualine Rugebregt

Institutions
Research Center of Oceanography - LIPI

Abstract
Abstract. Changes in pH, temperature, and salinity in seawater can indicate the occurrence of ocean acidification. This study aims to study changes in acidity that occur in Ohoililir waters, Southeast Maluku, which is part of the Banda Sea. This research was conducted in March 2019 as a study of the prefix of oceanic equities in the Southeast Maluku region which is part of the Banda Sea which is currently one of the priority researches in Indonesia, and sampling at 10 points associated with coral reefs and seagrass ecosystems. The results obtained were pH ranging from 8.567 – 8.851 with an average of 8.6879, temperatures ranged from 29.285 – 30.281oC with an average of 29,7412°C, and salinity ranged from 33.041-33.33 with an average of 33,2355. Its shows that pH, temperature, and salinity of Ohoililir waters are still a good range for the life of marine biota.The correlation between pH and temperature is -0.097 and the correlation between pH and salinity is in the range of -0.054 which indicates has no relationship between pH and temperature and salinity. Beside that, pH has negative correlation to temperature and salinity. This shows the need for further research on the relationship between these three or more parameters to see the effect on ocean acidification.

Keywords
pH, temperature, salinity, ocean acidification, Ohoililir

Topic
Coastal and Ocean Dynamics

Link: https://ifory.id/abstract/JTBMgxRNw6nj

Corresponding Author
Camellia Kusuma Tito

Institutions
Institute for Marine Research and Observation
Ministry of Marine Affairs and Fisheries
Jl. Baru Perancak, Jembrana, Bali, 82251, Indonesia

Abstract
Coral reefs facing climatic challenges due to increased carbon dioxide (CO2) concentration in the atmosphere, elevated sea surface temperatures (SST) and sea level anomaly (SLA). Recent works highlighted that El Niño-Southern Oscillation (ENSO) increases SST and induces bleaching events in several region. Meanwhile, SLA impacts on coral reefs have rarely been addressed but could be more important for reefflat ecosystem than previously thought. The objective of this work is to assess SLA impacts on Tomini-s reef coral bleaching stress. In 1998, 2010 and 2016 Tomini-s reef coral experienced severe bleaching period during hot spot (HS) occupied in a certain water body on certain time, called degree of heating weeks (DHW, 0C-week). Long term (1993-2019) SLA data acquired from multimission altimetry satellite by Copernicus Marine Environment Monitoring Service (CMEMS) were used in the analysis. The results show that the slope of SLA in Tomini Bay tend to increased for the last three decades. Therefore, we suggest that effects of combined rising SST and SLA could be increased Tomini-s reef coral bleaching stress.

Keywords
Bleaching, Coral reef, Sea level anomaly, Sea surface temperature

Topic
Coastal and Ocean Dynamics

Link: https://ifory.id/abstract/yNJ2496xHbFY

Corresponding Author
Riza Yuliratno Setiawan

Institutions
a) Department of Fisheries, Faculty of Agriculture, Universitas Gadjah Mada, Jl. Flora Gd. A4, Bulaksumur, Yogyakarta 55281, Indonesia
*riza.y.setiawan[at]ugm.ac.id
b) Department of Oceanography, Faculty of Fisheries and Marine Sciences, Diponegoro University, Jl. Prof. Soedarto, S.H., Tembalang, Semarang 50275, Indonesia
c) Department of Physics, Faculty of Mathematics and Natural Sciences, Universitas Sriwijaya. Jl. Palembang - Prabumulih, Km. 32, Inderalaya, OI, Sumatra Selatan, 30662, Indonesia

Abstract
Long-term satellite data (2003-2017) are analyzed to investigate the variability of ocean surface chlorophyll-a (Chl-a) concentration off the Halmahera Island under influence of the Indonesian Australian Monsoon and the El Niño-Southern Oscillation (ENSO). In this study, we first analyzed the seasonal variability of Chl-a, and then describe the relationship between sea surface Chl-a, sea surface temperature (SST), and sea surface wind stress in the region. Our results demonstrate that prevailing northerly and southeasterly wind stresses play a pivotal role in generating Chl-a maxima off the Halmahera Island. On seasonal time scale, the strengthening of northerly and southeasterly wind stresses (up to ~0.01 N m-2) during the Northwest and Southeast Monsoon seasons produce enhanced phytoplankton blooms associated with sea surface cooling (~28.8 °C) in the area of study. On interannual time scale, the largest positive Chl-a and wind stress anomalies and the coolest SST anomaly are observed in 2006 during El Niño event. Meanwhile, the greatest negative Chl-a anomaly is prevailed during the 2016 negative IOD event. This study demonstrates that wind variability is the essential factor in determining the magnitude of Chl-a maxima off the Halmahera Island.

Keywords
Chlorophyll-a; ENSO; Halmahera Island

Topic
Coastal and Ocean Dynamics

Link: https://ifory.id/abstract/u8QchJ6arb3Y

Corresponding Author
Wahyu Setyo Kuntoro

Institutions
1)Study Program of Oceanography, Faculty of Earth Sciences and Technology, Bandung Institute of Technology
2)Research Group of Oceanography, Faculty of Earth Sciences and Technology, Bandung Institute of Technology
*Corresponding author: nining[at]fitb.itb.ac.id

Abstract
Seasonal characteristics of wave height in Southern Bali waters in 2014 was simulated using SWAN (Simulating Wave Nearshore) model with the resolution of 1/216° (0.51 km). The model was forced using Cross Calibrated Multi Purposed (CCMP) wind data with resolution 1/4° (27.75 km) and 1/600° (0.18 km) bathymetry data derived from Batimetri Nasional (BATNAS) provided by Geospatial Information Agency (BIG). The result shows that the highest (lowest) seasonal average of Significant Wave Height (SWH) in Southern Bali waters (SBW) in 2014 during east (west) monsoon or JJA (DJF) on June-July-August (December-January-February) months was about 2.2 m (1.4 m). Meanwhile, SWH during the first (second) transitional monsoon or MAM (SON) on March-April-March (September-October-November) months was about 1.7 m (2.1 m). The 2D spectrum analysis exhibits that seasonal wave characteristic in Southern Bali waters (SBW) was dominated by swell propagation from the Indian Ocean (IO). Corresponding to the SWH, seasonal average of wave energy spectrum during east monsoon (JJA) shows that the highest value is up to 0.0038 m2s/deg compared to the other seasons.

Keywords
Wave height, SWAN (Simulating Wave Nearshore), Southern Bali, seasonal characteristics

Topic
Coastal and Ocean Dynamics

Link: https://ifory.id/abstract/XD4LAhQV9Czx

Corresponding Author
Hanif Santyabudhi Sutiyoso

Institutions
a) Study Program of Oceanography, Institut Teknologi Bandung, Indonesia
*santyabudhi[at]oceanography.itb.ac.id

b) National University of Ireland Galway, Ireland

Abstract
Rip currents are hydrodynamic events that vary alongshore and important to be well-understood for its uniqueness and safety issues on recreational beaches. In this study, bathymetrically-controlled rips are the main focus as this type is commonly found on Indonesia-s coastal areas, particularly in the south coast of West Java. This unique hydrodynamics feature affects sediment characteristic, particularly at the rip channel as the lower part tends to have coarser sediment due to larger friction. Such complex interactions need thorough investigation, therefore, a study was conducted in Pangandaran which well-known for its rip currents. Field observation was made to collect sediment sample on a cross-shore direction which shows finer sediment on upper rip channel and coarser sediment on the lower part with a diameter size of 0.35 mm and 0.37 mm, respectively. In addition, simple simulations were also made to illustrate rip current movement on a channel. The result shows that in the strongest current area with over than 3.0 m/s current speed, i.e. on the lower part of the rip channel, bed shear stress is found to be the strongest. It is been noticed as well that the bed shear stress forms a pattern which delineates overall movement of a rip current. Furthermore, the variation of bed shear stress is revealed as the main cause of sediment distribution along the cross-shore direction. Therefore, this simple approach qualitatively illustrates the dynamics of a rip current phenomenon.

Keywords
rip current, coastal morphology, sediment, Delft3D

Topic
Coastal and Ocean Dynamics

Link: https://ifory.id/abstract/nKE4vQRUukT2

Corresponding Author
Alina Blume

Institutions
1EMR-Group, Geological Institute, RWTH Aachen University, Wuellnerstr. 2, 52056 Aachen, Germany
2Institute of Geosciences, Kiel University, Ludewig-Meyn-Str. 10, 24118 Kiel, Germany
3Indonesian Institute of Sciences (LIPI)-R.C for Geotechnology

Abstract
The Sea Surface Temperature (SST) of the western Indian Ocean shows a bimodal distribution caused by insolation changes and the migration of the Inter-Tropical Convergence Zone. Moreover, on inter-annual timescales, the western Indian Ocean is influenced by two monsoon periods and two seasonally-occurring events, the Indian Ocean Dipole (IOD) and the El Niño Southern Oscillation (ENSO). An understanding of paleoclimate is essential to better understand these ocean-atmosphere interactions and be able to predict future climate variability. Chemical analyses of corals allow us to reconstruct SST changes in high resolution (monthly-seasonal) and therefore help us to link them to seasonal insolation pattern variations caused by orbital forcing. Here, we use a Sr/Ca record of a fossil Porites coral, which is dated to the mid-Holocene (6k) and covers 16 years. Sr/Ca-ratios were measured using ICP-OES with simultaneous data acquisition. The results show variations in the bimodality and average maximum temperatures of each year. A sudden increase in SST by 1.66° C lasted for about 5 years and suggests a possible positive IOD/ENSO-event.

Keywords
Sr/Ca, coral, SST

Topic
Coastal and Ocean Dynamics

Link: https://ifory.id/abstract/HrZPM6A4tCay

Corresponding Author
I Putu Ranu Fajar Maharta

Institutions
a) Faculty of Earth Sciences and Technology, Bandung Institute of Technology, Jalan Ganesha 10, Bandung 40132, Indonesia
*ranufajar123[at]gmail.com
b) Faculty of Marine Science, Udayana University, Kampus Bukit Jimbaran, Badung 82121, Indonesia

Abstract
Bali Strait is one of the most unique and important water areas, especially for the coastal communities of Banyuwangi and Jembrana up to Badung Regency. The Bali Strait has Sardinella lemuru fish resources where it is widely exploited and is the main livelihood income of the coastal communities. In recent years, the quality of Sardinella lemuru fish has begun to decline due to contamination of microscopic plastic debris in the Bali Strait during western monsoon. Many previous researches have carried out the movement of debris in the Bali Strait using numerical model to find out the source and location of the marine debris, however it only carried out local simulations within the Bali Strait. This study aims to determine the movement of debris that reaches the Bali Strait assuming debris originates from coastal areas on south and west coast of Sumatra and Java during the western monsoon (December 2018 - February 2019). The Finite Volume Coastal Ocean Model (FVCOM) model is used to obtain circulation of current patterns and debris particles movement patterns using the Lagrangian Particle Tracking module. The verification result of the model current pattern and field data using the Root Mean Square Error (RMSE) equation. In the u velocity component the RMSE value is 0.014 m/s with a correlation of 0.968 and the v velocity component is 0.011 m/s with a correlation of 0.945. In general, the current pattern in the waters of south of Sumatra Island to Java Island in the dominant western monsoon moves eastward due to the influence of western monsoon. The simulation results show particles that reached the Bali Strait as much as 3.47% originating only from the coastal waters of East Java.

Keywords
Bali Strait; FVCOM; lagrange; marine debris

Topic
Coastal and Ocean Dynamics

Link: https://ifory.id/abstract/WQ2YTLwt7KC4

Corresponding Author
Riski Indah

Institutions
Faculty of Mathematics and Science, Mulawarman University, East Kalimantan

Abstract
Mahakam Delta is a delta with unique characteristics. As a result of the continuous sedimentation process, the delta can be said as a complex delta because it has dozens of tributaries that are interconnected and flow into the sea to their estuaries. Mahakam Delta estuary is a meeting place for mixing masses of water from freshwater rivers and high salinity rivers. The aim of this study is to determine the water column stratification seen from the salinity and temperature parameters in the Mahakam Delta estuary. This study uses the ECOMSED model which is run for 40 days (July 7 to August 16, 2018) with tides and river discharge as the generating force. The simulation results show that stratification is predominantly influenced by differences in salinity between the layers. The strongest stratification is located in the upper Mahakam Delta line with a difference in salinity is 8 ppm from surface to bottom layer.

Keywords
Mahakam Delta Estuary; Salinity; Temperature

Topic
Coastal and Ocean Dynamics

Link: https://ifory.id/abstract/kZVy7Gpb9NKj

Corresponding Author
Nanda Nur Anugrah

Institutions
a) Marine Science Department, Hasanuddin University
Jl. Perintis Kemerdekaan 10, Makassar, 90245, Indonesia.
b) Institute for Marine Research and Observation, Ministry of Marine Affairs and Fisheries, Jl. Baru Perancak, Negara, Jembrana - Bali 82251.

Abstract
The Makassar Strait is one of the main gate of Arus Lintas Indonesia (Arlindo) which carries water masses from the Pacific Ocean and causes Makassar Strait waters affected by the El Nina and La Nina phenomenon. This study aims to observe the oceanographic characteristics of the Makassar Strait when El Nino and La Nina phenomena occur by looking at the changes in temperature, salinity, and currents from 2009-2010. The data used in this research are sea surface temperature data (CMEMS), Salinity (CMEMS) and current speed (CMEMS) which are processed using Panoply applications and Sea Surface Temperature data from Climate Prediction Center (NOAA) processed into Oceanic Nino Index (ONI). In the period from 2009 - 2019 there were three times the ENSO anomaly phenomenon, which began with the El Nino phenomenon from September 2009 to March 2010, then La Nina in July 2010 to May 2011, and El Nino in May 2015 to May 2016 In each phase, the dynamics of oceanographic characteristics occur in the waters of the Makassar Strait which cause fluctuations in sea surface temperature, salinity, and currents that have interacted to each other

Keywords
El Nino, La Nina, Makassar Strait, Sea Surface Temperature (SST)

Topic
Coastal and Ocean Dynamics

Link: https://ifory.id/abstract/ZzeGD6Y9tHRC

Corresponding Author
iis triyulianti

Institutions
Balai Riset dan Observasi Laut, Perancak, Bali.

Abstract
The Eastern of Indonesian Sea waters as a part of Indonesian Sea Large Marine Ecosystem accomodates the Tropical Ocean Productivity. Those regions also have an important sites for Indonesian fisheries. As a part of the Tropical Ocean Productivity contains of chlorophyll-a and Carbon Organic concentrations. The amount of organic carbon manufactured by primay producers through a photosynthesis process. However, the primary producers immediately respire some of the organic carbon for their own energy, so the rest organic carbon that is available as food for the higher trophic levels called Net Primary Productivity (NPP). The aim of this study was to investigate the current profiles of chlorophyll-a and carbon organic from Net Primary Productivity concentrations based on in-situ measurement. We measured chlorophyll-a and organic carbon concentrationsat surface layer or in the euphotic zone on a cruise carried in 2017 at Banda, Maluku and Sulawesi Seas.The study reveals that the range of chlorophyll-a and organic carbon concentration were 0.1 – 0.75 mg/m3 and -0.076 – 0.338 mg C/m3/d in Banda Sea. The higher chlorophyll and organic carbon concentrations found in Maluku dan Sulawesi Seas with the range value were 0.4441 – 1.137 mg/m3 and -0.680 – 8.789 mg C/m3/d. These study results indicate that there was general relationship between chlorophyll a concentrations and organic carbon from Net Primary Productivity in the euphotic layers.This study suggests that the water fertility assosiated with chlorophyll a in Maluku and Sulawesi Seas are categorized as mesotrophic water and oligotrophic water for Banda Sea.

Keywords
Cholorophyll a, Organic Carbon, Net primary Productivity, The Eastern of Indonesian Sea Waters.

Topic
Coastal and Ocean Dynamics

Link: https://ifory.id/abstract/24RmJqTZUvBY