scholarly journals The Indonesian Throughflow and its Impact on Biogeochemistry in the Indonesian Seas

2020 ◽  
Vol 37 (1) ◽  
Author(s):  
Edwards Taufiqurrahman ◽  
A’an J. Wahyudi ◽  
Yukio Masumoto
Keyword(s):  
Global Ocean ◽  
Physical Parameters ◽  
Indonesian Throughflow ◽  
Mixing Processes ◽  
Indonesian Seas ◽  
Marine Biogeochemistry ◽  
Strong Relation ◽  
Climate Systems ◽  
Critical Aspects

It has been widely known that the Indonesian Throughflow (ITF) is an important inter-ocean connection with unique and complex oceanographic and geographic conditions, as well as a strong relation to both regional and global ocean currents and climate systems. Many studies on characteristics, mechanisms, and impacts of the ITF have been conducted, mainly focusing on the ITF pathways, transport, water mass mixing processes, and their variability in connection with monsoons and climate systems. In this paper, we summarize some of the critical aspects related to ocean conditions within the Indonesian Seas and the Indonesian Throughflow, with the main focus on studies of marine biogeochemistry in a region affected by the ITF. Although the biogeochemical cycle is one of the key research topics that are needed to advance our ocean understanding, studies on marine biogeochemistry within the Indonesian Seas are quite limited due to less observed data compared to the physical parameters. Further studies on biogeochemistry and efforts to conduct in situ and remotely sensed observations in this region are strongly required. Here, we propose several biogeochemical observations correlated to the ITF.

Rapid Determination of Organic Matter Fractions by Ozonation Chemiluminescence

2012 ◽  
Vol 468-471 ◽  
pp. 2842-2848 ◽  
Author(s):  
Yan Liu ◽  
Ping Ping Fan ◽  
Guang Li Hou ◽  
Ji Chang Sun ◽  
Yan Cheng ◽  
...  
Keyword(s):  
Organic Matter ◽  
Rapid Determination ◽  
In Situ Monitoring ◽  
Global Ocean ◽  
Sediment Chemistry ◽  
Marine Biogeochemistry ◽  
Organic Matter Fractions ◽  
Soluble Fractions

Understanding marine biogeochemistry requires a network of global ocean in situ monitoring of various parameters on different scales in time and space. Among the various parameters involved in marine biogeochemistry, sediment chemistry is most important, and the organic matter fractions are the dominate factor in this parameter. However, classical methods of determining organic matter fractions consume a great deal of time and labor. In addition, some of these methods can produce high levels of pollution and are therefore not suitable for in situ studies. This study explored a method of rapid determination of organic matter fractions by ozonation chemiluminescence. In this method, the organic matter was separated into extractives, acid soluble fractions and acid insoluble fractions (AIF) using the classical method and then oxidized by ozone. The ozonation chemiluminescence characteristics of eight samples were subsequently used to set up a model to predict the concentrations of organic matter fractions. The model was tested using nine other organic samples and the results showed that it provided a better fit for the predicted acid soluble fractions. This study is the first to demonstrate the use of ozonation chemiluminescence for rapid determination of organic matter fractions; however, further study is required to enable its universal use.

A New Estimate of Global Ocean Climatology

2021 ◽  
Author(s):  
Kanwal Shahzadi ◽  
Nadia Pinardi ◽  
Marco Zavaterelli ◽  
Simona Simoncelli
Keyword(s):  
Quality Control ◽  
World Ocean ◽  
Global Ocean ◽  
Physical Parameters ◽  
Oxygen Utilization ◽  
Non Linear ◽  
Using Data ◽  
The Impact ◽  
Apparent Oxygen Utilization

<p>The estimation of climatology is a key element for improving our understanding of the ocean state. Historical data sets available today enables an almost complete reconstruction of global ocean fields. In this study, a new global ocean climatological estimate of basic physical parameters such as temperature, salinity, density, dissolved oxygen, and apparent oxygen utilization is computed using the World Ocean Database (WOD18). The reliability of estimate is closely tied to the quality assurance of the in-situ observations and statistical interpolation schemes of the mapping. Therefore, in this context, WOD18 used for this study has gone through a non-linear quality control procedure developed by Shahzadi (2020) on a global domain. The mapping of resulting data is carried out using Data Interpolating Variational Analysis (DIVA). Sensitivity experiments are carried out to choose the key parameters of DIVA, namely the horizontal correlation lengths, and the Noise to Signal ratio (N/S). Furthermore, two new indices such as roughness index, and root mean square of residuals are designed to show the impact of the correlation length, and N/S ratio choices. For temperature and salinity, two different versions of the climatological estimates are produced: (i) a long-term (1900 to 2017) climatology using multiple platforms in-situ data, and (ii) a shorter time estimate (2003-2017) using data from ocean drifting platforms such as profiling floats. The two versions are intercompared and differences are evaluated.  Similar procedures are applied for global mapping of Density, Oxygen, and Apparent Oxygen utilization. The new climatological estimates are compared with previous estimates such as World Ocean Atlas and World Argo Global Hydrographic climatological estimates, and thereby the differences are analysed.</p><p><strong>Keywords:</strong> WOD18, temperature, salinity, apparent oxygen, DIVA, climatology, non-linear quality control.</p><p>Shahzadi, K., (2020): “A New Global Ocean Climatology”, Ph.D. Thesis (under evaluation), University of Bologna, Italy, pp. (19-35. of pages)</p>

scholarly journals Evaluation of an operational ocean model configuration at 1/12° spatial resolution for the Indonesian seas (NEMO2.3/INDO12) – Part 2: Biogeochemistry

2016 ◽  
Vol 9 (4) ◽  
pp. 1523-1543 ◽  
Author(s):  
Elodie Gutknecht ◽  
Guillaume Reffray ◽  
Marion Gehlen ◽  
Iis Triyulianti ◽  
Dessy Berlianty ◽  
...  
Keyword(s):  
Primary Production ◽  
Chlorophyll A ◽  
Net Primary Production ◽  
Ocean Model ◽  
Global Ocean ◽  
Open Boundary ◽  
Indonesian Seas ◽  
Forecasting System ◽  
Ocean Forecasting

Abstract. In the framework of the INDESO (Infrastructure Development of Space Oceanography) project, an operational ocean forecasting system was developed to monitor the state of the Indonesian seas in terms of circulation, biogeochemistry and fisheries. This forecasting system combines a suite of numerical models connecting physical and biogeochemical variables to population dynamics of large marine predators (tunas). The physical–biogeochemical coupled component (the INDO12BIO configuration) covers a large region extending from the western Pacific Ocean to the eastern Indian Ocean at 1/12° horizontal resolution. The NEMO-OPA (Nucleus for European Model of the Ocean) physical ocean model and the PISCES (Pelagic Interactions Scheme for Carbon and Ecosystem Studies) biogeochemical model are running simultaneously ("online" coupling), at the same resolution. The operational global ocean forecasting system (1/4°) operated by Mercator Océan provides the physical forcing, while climatological open boundary conditions are prescribed for the biogeochemistry. This paper describes the skill assessment of the INDO12BIO configuration. Model skill is assessed by evaluating a reference hindcast simulation covering the last 8 years (2007–2014). Model results are compared to satellite, climatological and in situ observations. Diagnostics are performed on nutrients, oxygen, chlorophyll a, net primary production and mesozooplankton. The model reproduces large-scale distributions of nutrients, oxygen, chlorophyll a, net primary production and mesozooplankton biomasses. Modelled vertical distributions of nutrients and oxygen are comparable to in situ data sets although gradients are slightly smoothed. The model simulates realistic biogeochemical characteristics of North Pacific tropical waters entering in the archipelago. Hydrodynamic transformation of water masses across the Indonesian archipelago allows for conserving nitrate and oxygen vertical distribution close to observations, in the Banda Sea and at the exit of the archipelago. While the model overestimates the mean surface chlorophyll a, the seasonal cycle is in phase with satellite estimations, with higher chlorophyll a concentrations in the southern part of the archipelago during the SE monsoon and in the northern part during the NW monsoon. The time series of chlorophyll a anomalies suggests that meteorological and ocean physical processes that drive the interannual variability of biogeochemical properties in the Indonesian region are reproduced by the model.

scholarly journals Air-Sea Interactions over Eddies in the Brazil-Malvinas Confluence

2021 ◽  
Vol 13 (7) ◽  
pp. 1335
Author(s):  
Ronald Souza ◽  
Luciano Pezzi ◽  
Sebastiaan Swart ◽  
Fabrício Oliveira ◽  
Marcelo Santini
Keyword(s):  
Latent Heat ◽  
Large Scale ◽  
Surface Wind ◽  
Heat Fluxes ◽  
Lower Atmosphere ◽  
Meteorological Variables ◽  
Global Ocean ◽  
Study Region ◽  
Cold Core

The Brazil–Malvinas Confluence (BMC) is one of the most dynamical regions of the global ocean. Its variability is dominated by the mesoscale, mainly expressed by the presence of meanders and eddies, which are understood to be local regulators of air-sea interaction processes. The objective of this work is to study the local modulation of air-sea interaction variables by the presence of either a warm (ED1) and a cold core (ED2) eddy, present in the BMC, during September to November 2013. The translation and lifespans of both eddies were determined using satellite-derived sea level anomaly (SLA) data. Time series of satellite-derived surface wind data, as well as these and other meteorological variables, retrieved from ERA5 reanalysis at the eddies’ successive positions in time, allowed us to investigate the temporal modulation of the lower atmosphere by the eddies’ presence along their translation and lifespan. The reanalysis data indicate a mean increase of 78% in sensible and 55% in latent heat fluxes along the warm eddy trajectory in comparison to the surrounding ocean of the study region. Over the cold core eddy, on the other hand, we noticed a mean reduction of 49% and 25% in sensible and latent heat fluxes, respectively, compared to the adjacent ocean. Additionally, a field campaign observed both eddies and the lower atmosphere from ship-borne observations before, during and after crossing both eddies in the study region during October 2013. The presence of the eddies was imprinted on several surface meteorological variables depending on the sea surface temperature (SST) in the eddy cores. In situ oceanographic and meteorological data, together with high frequency micrometeorological data, were also used here to demonstrate that the local, rather than the large scale forcing of the eddies on the atmosphere above, is, as expected, the principal driver of air-sea interaction when transient atmospheric systems are stable (not actively varying) in the study region. We also make use of the in situ data to show the differences (biases) between bulk heat flux estimates (used on atmospheric reanalysis products) and eddy covariance measurements (taken as “sea truth”) of both sensible and latent heat fluxes. The findings demonstrate the importance of short-term changes (minutes to hours) in both the atmosphere and the ocean in contributing to these biases. We conclude by emphasizing the importance of the mesoscale oceanographic structures in the BMC on impacting local air-sea heat fluxes and the marine atmospheric boundary layer stability, especially under large scale, high-pressure atmospheric conditions.

Estimating Global Ocean Heat Content Changes in the Upper 1800 m since 1950 and the Influence of Climatology Choice*

2014 ◽  
Vol 27 (5) ◽  
pp. 1945-1957 ◽  
Author(s):  
John M. Lyman ◽  
Gregory C. Johnson
Keyword(s):  
Heat Content ◽  
Ocean Heat Content ◽  
Global Ocean ◽  
Ocean Temperature ◽  
Vertical Separation ◽  
Ocean Heat Uptake ◽  
Expendable Bathythermograph ◽  
Heat Uptake ◽  
The Mean

Abstract Ocean heat content anomalies are analyzed from 1950 to 2011 in five distinct depth layers (0–100, 100–300, 300–700, 700–900, and 900–1800 m). These layers correspond to historic increases in common maximum sampling depths of ocean temperature measurements with time, as different instruments—mechanical bathythermograph (MBT), shallow expendable bathythermograph (XBT), deep XBT, early sometimes shallower Argo profiling floats, and recent Argo floats capable of worldwide sampling to 2000 m—have come into widespread use. This vertical separation of maps allows computation of annual ocean heat content anomalies and their sampling uncertainties back to 1950 while taking account of in situ sampling advances and changing sampling patterns. The 0–100-m layer is measured over 50% of the globe annually starting in 1956, the 100–300-m layer starting in 1967, the 300–700-m layer starting in 1983, and the deepest two layers considered here starting in 2003 and 2004, during the implementation of Argo. Furthermore, global ocean heat uptake estimates since 1950 depend strongly on assumptions made concerning changes in undersampled or unsampled ocean regions. If unsampled areas are assumed to have zero anomalies and are included in the global integrals, the choice of climatological reference from which anomalies are estimated can strongly influence the global integral values and their trend: the sparser the sampling and the bigger the mean difference between climatological and actual values, the larger the influence.

scholarly journals Análise Espaço-Temporal da Pluma de Dispersão dos Sedimentos Dragados do Porto de Maceió, Alagoas

2021 ◽  
pp. 2087-2113
Author(s):  
Anderson Marques Araújo do Nascimento ◽  
Paulo Ricardo Petter Medeiros ◽  
Geovânia Ricardo dos Santos ◽  
Geórgenes Hilário Cavalcante Segundo
Keyword(s):  
Gravimetric Method ◽  
Linear Interpolation ◽  
Particulate Material ◽  
Physical Parameters ◽  
Plot Analysis ◽  
Suspended Particulate ◽  
Suspended Particulate Material ◽  
Sedimentary Dynamics ◽  
Box Plot

The understanding of the sedimentary dynamics is important in the characterization of impacts caused by dredging and this knowledge becomes decisive for their discernment. The aim of this article was to analyze the plume of dispersion of the sediments of the Port of Maceió. The analyzes were carried out in three sampling campaigns, before, during and after the port works, in which the collection points in the dredging and discard areas were plotted. The suspended particulate material (SPM) was analyzed using the gravimetric method and in situ sampling of the parameters turbidity, dissolved oxygen and percentage of saturation, salinity and electrical conductivity with a multiparameter probe and water transparency with Secchi disk. The parameters SPM, turbidity and transparency were analyzed by linear interpolation, while the other variables were subjected to analysis on a polynomial calibration curve. The multiparameters worked were submitted to box plot analysis in order to assess the variance between campaigns. The variation of SPM in the sample campaigns showed dynamic spatial and temporal behavior; The interpolation promoted a better visualization of the physical parameters that directly express the plume of dispersion; The supplementary variables showed trend patterns in relation to the sediment charge; Box plot analysis proved to be pertinently useful for evaluating and interpreting the results in an integrated manner, mainly due to the large number of parameters analyzed; The dredging works had a balanced management between the amount of dredged sediments and their spatial disposition at the discard site when compared to the dredging area.

scholarly journals Validation of Sea Surface Temperature from GCOM-C Satellite Using iQuam Datasets and MUR-SST in Indonesian Waters

2021 ◽  
Vol 53 (1) ◽  
Author(s):  
Bambang Sukresno ◽  
Dinarika Jatisworo ◽  
Rizki Hanintyo
Keyword(s):  
High Resolution ◽  
Error Analysis ◽  
Surface Temperature ◽  
Sea Surface Temperature ◽  
Important Variable ◽  
Sea Surface ◽  
Analysis Method ◽  
Validation Process ◽  
Indonesian Seas

Sea surface temperature (SST) is an important variable in oceanography. One of the SST data can be obtained from the Global Observation Mission-Climate (GCOM-C) satellite. Therefore, this data needs to be validated before being applied in various fields. This study aimed to validate SST data from the GCOM-C satellite in the Indonesian Seas. Validation was performed using the data of Multi-sensor Ultra-high Resolution sea surface temperature (MUR-SST) and in situ sea surface temperature Quality Monitor (iQuam). The data used are the daily GCOM-C SST dataset from January to December 2018, as well as the daily dataset from MUR-SST and iQuam in the same period. The validation process was carried out using the three-way error analysis method. The results showed that the accuracy of the GCOM-C SST was 0.37oC.

In Situ Thermal Response Test Methods And Practices

2011 ◽  
Vol 347-353 ◽  
pp. 3087-3092
Author(s):  
Qiang Li ◽  
You Hong Sun ◽  
Xin Fang
Keyword(s):  
High Efficiency ◽  
Thermal Response ◽  
Clean Energy ◽  
Heat Pumps ◽  
Testing Equipment ◽  
Physical Parameters ◽  
Geothermal Wells ◽  
Response Testing ◽  
Thermal Physical Parameters

Abstract. As a high efficiency, low consumption and clean energy, ground source heat pump technology has been pay more and more attention, the number of installation of system is growing rapidly. However, the use of geothermal resources is still extensive at this stage. Effective methods are pure in obtaining thermal physical parameters of geothermal wells around. In-situ thermal response testing is close to the real use of heat pumps, when injecting in or extracting heat from geothermal wells, the testing equipment will collect data, and then thermal physical parameters will be accurately calculate. This paper introduce a thermal response testing equipment, the equipment will add a constant cold or heat to geothermal well, circulating heat flow and pressure data is collected as well as temperature. And then thermal physical parameters of formation and heat exchanging performance are calculated.

scholarly journals Laboratory investigations of the physical parameters influencing the in situ leaching of tungsten

Geothermics ◽  
2021 ◽  
Vol 89 ◽  
pp. 101992
Author(s):  
Máté Osvald ◽  
Andrew Kilpatrick ◽  
Christopher A. Rochelle ◽  
János Szanyi ◽  
Béla Raucsik ◽  
...  
Keyword(s):  
Physical Parameters ◽  
Laboratory Investigations
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