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The responses of surface wind stress to the mesoscale sea surface temperature (SST) anomalies associated with the SST front in the northern South China Sea (NSCS) are studied using satellite observations and reanalysis data. Both satellite and reanalysis data explicitly show the linear relationships between the spatial-high-pass filtered wind stress perturbation derivatives and the underlying SST gradient field. However, the noise in the linear relationships is much smaller in the reanalysis data than in the satellite observations. This result is rarely reported in other frontal areas. The wavelet analysis shows that the satellite scatterometer observed numerous high wavenumber perturbations within 100 km in the NSCS, but these perturbations were absent in the reanalysis data. The linear relationship between the perturbation SST gradient and derivative wind stress fields is not significant at this scale, which enhances the noise in the linear relationship. The spatial bandpass-filtered perturbation between 100 and 300 km can give reasonable estimates of the coupling coefficients between the wind stress divergence and downwind SST gradient (αd) and between the wind stress curl and crosswind SST gradient (αc) in the NSCS, with values of 1.33 × 10−2 and 0.95 × 10−2 N m−2 °C−1, respectively.

The loudspeakers of thermal front are studied in the dried-out products in the Termika sunny drying setting of. An experimental stand is worked out for the study of dynamics of development of thermal front in the objects of drying, an experimental base is created for the conduct of experimental researches on the exposure of speed of distribution of temperature in the volume of object of drying. On the base of the created experimental stand experimental studies are undertaken in Termika, Individual SDS, and outdoors. Comparative data are got, characterizing the loud speakers of development of thermal front in the objects of drying. It is experimentally well-proven that presence of additional source of infrared in the chamber of drying as a metallic rib of perpendicular relatively overhead metallic sheet — heat-exchanger allows to promote speeds of drying.

The present study identifies wintertime cold fronts in Eurasia from gridded datasets using a new objective two-step identification scheme. The simple and classic conception of a front is adopted, where a cold front is identified as the warm boundary of the frontal zone with a suitable horizontal temperature gradient and cold advection. We combine the traditional thermal front parameter with temperature advection to first identify the cold frontal zone, and then its eastern and southern boundaries are objectively plotted as a cold front in Eurasia. By comparing different cold front identification methods, the results from this two-step cold front identification method and subjective analysis are more consistent, and the positions of the cold front identified with our method are more reasonable. This objective technique is also applied to a nationwide cold wave event over China. Results show that the horizontal extent and movement of the cold front are in good agreement with the related circulation and the associated cold weather. The proposed method and results in this study may shed light on the rapid identification of cold fronts in operational weather analysis and facilitate further research on the long-term activity characteristics of continental cold fronts.

This research was conducted in August to November 2019. It aims to determine the potential fishing ground based on thermal front and upwelling in the waters of West Sumatra. The survey method was applied in this research. The results showed that the distribution of thermal front and upwelling in the waters of West Sumatra experienced a change that was not too significant. Based on the results of sea surface temperature verification on the Aqua MODIS image with the temperature in the field obtained temperature differences of around ± 10C. The catch during the research shows that catches in the thermal front area can be used as a potential fishing ground because the catch in the thermal front area is more than the area outside the thermal front

Thermal front didefinisikan sebagai pertemuan antara dua masa air dengan karakteristik suhu yang berbeda sehingga membentuk gradien suhu. Thermal front merupakan salah satu proses oseanografi penting yang dapat mempengaruhi kondisi fisik, kimia, maupun biologi di laut. Tujuan dari penelitian ini adalah untuk mengetahui sebaran thermal front musiman di perairan Selat Madura, Jawa Timur. Deteksi thermal front dilakukan pada lapisan permukaan laut dengan menggunakan citra AquaMODIS untuk suhu permukaan laut. Citra AquaMODIS yang digunakan memiliki resolusi spasial sebesar 1 km x 1 km dan resolusi temporal selama satu hari. Metode yang digunakan untuk mendeteksi fenomena ini adalah metode Single Image Edge Detection (SIED) yang diperkenalkan oleh Cayula dan Cornilon pada tahun 1992. Metode ini menggunakan prinsip deteksi tepi piksel yang mempertimbangkan nilai gradien suhu dan pola arah dari piksel yang memiliki gradien suhu. Hasil yang diperoleh berupa sebaran spasial dan temporal fenomena thermal front di perairan Selat Madura. Sebaran temporal berdasarkan komposit harian dalam satu musim selama empat tahun dari tahun 2012 – 2016. Rata – rata kejadian thermal front tiap musim sebanyak 446 kali pada musim barat, 1893 kali pada musim peralihan I, 1038 kali pada musim timur, dan 2375 kali pada musim peralihan II. Penyebab utama kejadian front di perairan Selat Madura adalah akibat adanya arus eddy dan masukan masa air laut dari wilayah timur Selat Madura. Thermal front defined as an ecounter of two water masses which has different temperature (thermal) characteristics and create a thermal gradient. Thermal front is one of the most important oceanographic proceses that can make a significant impact to physical, chemical, and biological process in the ocean. The aim of this research is to understand seasonal thermal front distribution in Madura Strait, East Java. Thermal front was detected in the surface layer of water, using AquaMODIS for Sea Surface Temperature (SST). AquaMODIS image which used in this research has 1 km x 1 km spatial resolution and one day (24 hours) temporal resolution. Front detection in this research is using Single Image Edge Detection by Cayula Cornilon (1992). This method is using edge detection of pixel, considering the value of thermal gradient and pattern of the pixel edge. The result of this research is spatial and temporal distribution of thermal front in Madura Strait. Temporal distribution are based on composite result of daily front detection in seasonal range for four years from 2012-2016. Seasonal average of front occurence is 446 times in western season, 1893 times in Transition I, 1038 times in eastern season and 2375 times in Transition II. The main cause of front in Madura strait is eddy current and water masses ecounter from eastern area of Madura.

A new conceptual framework, based on ocean bio-physical observations from different satellites, has been proposed to track fishing ground parameters to identify Potential Fishing Zones (PFZ) in the...

Fronts are ubiquitous phenomena in oceans, and they play a significant role in marine hydrodynamics and ecology. During the stratified season of a shelf sea, the coastal front is usually considered as a single front, i.e., the tidal mixing front. However, using high resolution (~1 km) Multi-scale Ultra-high Resolution (MUR) analysis sea surface temperature (SST) data, this study observes persistent double fronts along the Yellow Sea coast in summertime. The double fronts comprise the well-known offshore tidal mixing front and a nearshore front, and the nearshore front has not been previously reported. The climatological (2002–2017) monthly mean result shows that the double fronts with two SST gradient peaks exceeding ~2 °C/100 km and opposite SST gradient directions basically remain unchanged from June to August, whereas the frontal spacing decreases in September. Analyses based on a two-layer concept model suggest that a topographic slope along with tidal mixing could induce the pattern of double fronts. The frontogenesis of nearshore thermal front could be associated with the different responses of the water column of different water depths to insolation. The offshore movement of the nearshore front in September could be related to the fast cooling of nearshore water and intensified offshore wind, and the topographic slope is important for determining the pattern of double fronts (loose or tight). This study shows a new pattern of coastal fronts in the stratified season, and indicates the significance of high resolution satellite data. The discovery of the double front pattern implies the influence of coastal fronts during the stratified season on marine ecology and environment in a shelf sea might be underestimated.

The Banda Sea is one of the routes of global ocean currents that move from the Pacific Ocean to the Indian Ocean. This flow is known as Indonesian Through Flow (ITF). The Banda Sea is an area where warm and cold water masses meet, so it has the potential for a thermal front. This study aims to understand the variability of thermal front in the Banda Sea during the El Nino Southern Oscillation period. Southern Oscillation Index (SOI) and sea surface temperature (SST) data in 2010, 2012 and 2015 were used in this study. SOI data was obtained from http://www.bom.gov.au and SST data was obtained from http://oceancolor.gsfc.nasa.gov. The data were processed using ArcGIS 10.4 software and Ms. Office 2013. The results showed the La Nina period occurs in July - December 2010, the Normal period occurs in July - December 2012, and the El Nino period occurs in May - October 2015. In general, during La Nina, the mean SST has higher values than the other periods. On the other hand, the highest thermal front occurs during the El Niño period (10584), followed by the Normal period (7544) and the lowest during the La Niña period (5961), respectively.

Potential fishing zone (PFZ) advisory is an essential guideline for the fishing community of India. Several studies have shown that high sea surface temperature (SST) gradient and high chlorophyll concentration in the ocean are the prospective areas for pelagic fish catch. ESSO-INCOIS provides advisories on PFZ on a daily basis using remotely sensed SST and chlorophyll-a data. The limitation of this advisory is that it does not give any information about the probable quantity of the fish. In this study, a hybrid decision tree model is developed for characterizing PFZ in the Indian Ocean. If SST gradient, persistence of SST gradient and chlorophyll concentration of any PFZ are given as the input variables, this model can classify the corresponding PFZ in terms of low, medium or high category of fish catch. According to this study, low SST gradient persistence and high SST gradient indicate possibility of high fish catch.

Aquifer thermal energy storage (ATES) has been confirmed to be an effective thermal energy storage method and medium-to-high-temperature (MHT) ATES is receiving renewed interest. To illustrate the thermal performance of MHT ATES systems in the presence of natural regional groundwater flow and facilitate the future implementation of such systems, simulations including the effect of thermal dispersion are performed for a typical confined ATES system that consists of doublet wells and is operated in cyclic mode. The simulation model is validated using experimental data. The sensitivity of the system performance to hydrogeological and design/operation parameters is assessed using the thermal front, thermal breakthrough time, characteristic tilting time, and thermal recovery ratio. Based on the simulation results, the rules governing the influence of these parameters are presented and feasible storage site conditions and design/operation parameters for MHT ATES application are suggested.

Dissolvedorganic carbon (DOC) was determined at the Gerlache Strait, a coastal area off the Northern Antarctic Peninsula, in the austral summers of 2015 and 2016 during NAUTILUS I and II cruises, respectively. Hydrographic conditions in the area were very different between the study years. Despite that, the surface mixed layer displayed higher DOC concentrations compared to intermediate and deeper waters, as a result of the strong water column stratification, for both years. DOC accumulation on the surface is significantly related to the net community production (NCP), and stronger when the nitrate surface deficit (ΔNO3-) is higher (2016). The presence of a surface/subsurface thermal front at the central Gerlache Strait likely promotes the export of surface-produced organic carbon to deeper layers. A weak correlation between DOC and apparent oxygen utilization (AOU) suggests that the degradationof organic carbon in the deeper water column has a small role in oxygen consumption (less than 10%). This “recalcitrant” DOC characteristic below the surface layers observed in this study is similar to that found twenty years ago in the same area (FRUELA campaign, early Summer 1995). The Gerlache Strait allows, as an adequate regional scale study, assessments on the efficiency of the export and distribution of organic carbon in deep water masses in view of the observed trends of freshening, cooling, and lightening in the Antarctic Peninsula shelf waters.

The ear-shaped thermal front (ESTF), formed by the convergence of the Yellow Sea Warm Current (YSWC) and the Shandong Coastal Current (SCC), is a very important oceanic phenomenon in the Yellow Sea (YS) in winter. In situ measurements and reanalysis datasets all demonstrate that the ESTF has been weakening during 1950s–1990s, and a similar weakening trend is also found in winter monsoon over the YS. Numerical experiments show that the weakening of winter monsoon can induce an anomalous circulation in the YS on multi-decadal timescale with northward anomalous currents along China’s coast and southward anomalous currents in the central YS—generally opposite to seasonal mean circulation. The anomalous circulation causes slowdown of the YSWC and the SCC, and thus weakens the ESTF. Since the ESTF plays important roles in regional ocean dynamics and air-sea interactions, its weakening has important implications for regional climate in the YS in winter.

To investigate the early life history of Seriola dumerili, we first validated otolith daily increments using reared fish (11?51 days after hatching). Four larval and early-juvenile S. dumerili were collected in May and July 2015 around the Penghu Islands, Taiwan (23.45?23.70 °N, 119.40?119.70 °E), by surface larval net towing, but not from drifting seaweeds. Seriola dumerili were caught at the thermal front, and the total lengths and ages ranged 7.4?42.5 mm and 18?56 days, respectively. Our results indicate that the hatching dates of S. dumerili were April to June and larvae may have been accumulated in the frontal zone before the juvenile phase., Ichthyological Research, 64(1), pp.145-150; 2017

Indonesia is a region that is directly adjacent to the Pacific Ocean and the Indian Ocean which allows a thermal front phenomenon. The purpose of this study was to identify the presence of thermal fronts based on seasonal variations and inter-annual variations in Indonesia waters. The data used in this study were Sea Surface Temperature (SST), Ocean Nino Index (ONI), and Dipole Mode Index (DMI) from January 2007 - December 2017 (11 years). The SST data was a level 3 Aqua Moderate Resolution Imaging Spectroradiometer (MODIS) satellite image data with a resolution of 4 km. SST data was analysed using remote sensing techniques and Geographic Information System (GIS). The results of this study indicated that the distribution of SST and thermal fronts were influenced by seasonal variations and inter-annual variations. The highest average thermal front event in Indonesian waters occurred in a combination of El-Nino and Positive Indian Ocean Dipole (IOD) conditions. The highest average thermal front incidence in Indonesian waters also occurred during the East Season, while the smallest average occurred during the Transition Season II. During West Season, Transition Season II, and East Season, the largest number of thermal fronts was found in Western Indonesian Waters. Meanwhile, in the Transition Season I, the largest number of thermal fronts was found in Central Indonesian Waters. Thermal fronts were often found when the SST of Indonesian waters were cooler than normal conditions. The cooler condition made the SST more heterogeneous and formulated the thermal front phenomenon.

Ketersediaan informasi tentang informasi Potensi Penangkapan Ikan (PPI) sangat diperlukan untuk meningkatkan produktivitas perikanan. Secara tradisional, nelayan memanfaatkan indera dan kebiasaan turun-temurun mereka untuk menentukan PPI. Secara tradisional, nelayan memanfaatkan panca indra dan kebiasaan yang bersifat turun-temurun untuk menentukan PPI. Cara ini, selain kurang efisien, juga bisa menyebabkan ekploitasi berlebihan jika kegiatan penangkapan ikan dilakukan pada tempat yang sama secara terus-menerus. Keberadaan teknologi penginderaan jauh dapat dimanfaatkan untuk penentuan PPI secara lebih cepat dengan tetap memperhatikan aspek akurasi dan sebaran spasial. Salah satu metode penentuan PPI berbasis data penginderaan jauh, memetakan daerah thermal front terlebih dahulu sebelum menentukan PPI melalui interpretasi manual berdasarkan keberadaan piksel diantara suhu perairan yang hangat dan dingin. Interpretasi manual memiliki keterbatasan, diantaranya: tergantung pada manusia dan memerlukan waktu yang lama. Untuk mengatasi keterbatasan tersebut, dalam penelitian ini, metode Single Image Edge Detection (SIED) yang dikembangkan oleh Cayulla dan Cornillon diaplikasikan dalam bentuk toolbox agar bisa digunakan secara otomatis. Data Suhu Permukaan Laut (SPL) yang diperoleh dari MODIS Level 2 (6 April 2018) selanjutnya diproses dengan menggunakan toolbox ini dan berhasil mendeteksi 22 titik PPI di perairan selatan Pulau Jawa. Sementara itu, deteksi PPI dengan metode Temperature Gradient Analysis (TGA) yang dilakukan secara manual menghasilkan 28 titik. Terdapat 20 lokasi titik yang sama menggunakan dua metode ini. Penggunaan metode SIED berbasis toolbox dapat mempercepat pemrosesan data, mengurangi kesalahan manusia dengan tingkat akurasi 64%.

The need for information on potential fishing zones based on remote sensing satellite data (ZPPI) in coastal waters is increasing. This study aims to create an information model of such zones in coastal waters (coastal ZPPI). The image data used include GHRSST, SNPP-VIIRS and MODIS-Aqua images acquired from September 1st-30th, 2018 and September 1st-30th, 2019, together with other supporting data. The coastal ZPPI information is based on the results of thermal front SST detection and overlaying this with chlorophyll-a. The method of determining the thermal front sea surface temperature (SST) used Single Image Edge Detection (SIED). The chlorophyll-a range used was in the mesotropic area (0.2-0.5 mg/m3). Coastal ZPPI coordinates were determined using the polygon centre of mass, while the coastal ZPPI information generated was only for coastal areas with a radius of between 4-12 nautical miles and was divided into two criteria, namely High Potential (HP) and Low Potential (LP). The results show that the coastal ZPPI models were suitable to determine fishing locations around Nias Island. The percentage of coastal ZPPI information generated was around 90% information monthly. In September 2018, 27 days of information were produced, consisting of 11 HP sets of coastal ZPPI information and 16 sets of LP information, while in September 2019 it was possible to produce 29 days of such information, comprising 11 sets of HP coastal ZPPI information and 18 LP sets. The use of SST parameters of GHRSST images and the addition of chlorophyll-a parameters to MODIS-Aqua images are very effective and efficient ways of supporting the provision of coastal ZPPI information in the waters of Nias Island and its surroundings.

San Jorge Bay (23° S) is characterised by a permanent coastal upwelling front and a thermal front that influence water circulation into the bay. This bay constantly receives effluents from different mining activities. Several studies have demonstrated different levels of heavy metals in waters and sediments within the bay. The clam Protothaca thaca is a bivalve with sedentary habits, which is distributed along the Peruvian and Chilean coasts and is exploited commercially. During 2010, clams were collected inside the bay: north (La Chimba), centre (Paraiso) and south (Llacolen), as well as from a site outside the bay (Bolsico). Haematological parameters, condition factor index, lesions, parasites and pathogens and heavy metal concentrations in clam tissues were determined. The health indicators of clams inhabiting the bay varied between sites. Clams inside the bay showed higher prevalence and intensity of parasites and lesions than those clams inhabiting the site outside the bay, which could be indicating the presence of some environmental stressor (e.g. heavy metals). This study is the first to evaluate the health status of organisms from San Jorge Bay, and our results support the hypothesis that clams P. thaca can be used to evaluate environmental quality.

Summer hydrographic data from 1971 to 2000 demonstrate the presence of bottom cold water (BCW) and a bottom thermal front around the BCW in a semienclosed sea in the Seto Inland Sea of Japan. The horizontal gradient of water temperature across the bottom front was larger in neap tide than in spring tide, which is the opposite the pattern observed in the fortnightly variations in other areas (e.g., the Irish Sea). A numerical model for the Inland Sea reproduced the presence of BCW and a bottom front as well as the same fortnightly variation in the horizontal gradient of water temperature across the bottom front as in observational data. Being the same BCW as those in other areas, the presence of BCW in the Inland Sea is also caused by spatial variation in tidal mixing. The intensification of the bottom front in neap tide in the Inland Sea results from a combination of tidal mixing and horizontal advection of warm water to the BCW. The presence of a bottom residual current in the direction across the bottom front results in the horizontal advection of warm water to the BCW, and its fortnightly variation is responsible for the fortnightly variation of the bottom front in the Inland Sea. The presence of the BCW induces a surface cyclonic circulation in the direction approximately along the bottom front; the intensification and weakening of the bottom front with the spring–neap tidal cycle, combined with the fortnightly variation in the bottom boundary layer thickness, produce a slightly stronger surface cyclonic circulation in neap tide than in spring tide.

Commercial exploitation of geothermal resources requires the disposal of large volumes of cooled brine in an environmentally acceptable way. Reinjection of cooled (i.e. spent) geothermal water has become a standard reservoir management strategy. Since injected fluids are typically much colder than the reservoir rock, this strategy results in the cooling of the region around the injection wells. Injected cool water may not have sufficient residence time in the reservoir to receive enough heat from surrounding hotter rock, resulting in temperature decrease at producing wells. Usually, the energy transport in geothermal reservoirs is calculated by use of sophisticated numerical simulators. In this paper we present analytical solution of simplified model of mass and heat transfer in fractured porous medium in one dimension, assuming constant rock temperature and neglecting small-scale effect connected with dispersion and heat conduction. The solution presented in this paper is applicable if thermal capacity of rock is high but the specific area is not sufficient for instant thermal equilibrium. This approach allows for better understanding the relation between fluid movement along the fractures and heat transfer between the rock matrix and fluid. Simple numerical experiments reported in the paper have shown the importance of specific surface area of naturally fractured rock, which influences the rate of exchange of heat between the fractures and the rock matrix.

This work presents the development of improved tracer techniques for monitoring internal temperatures and cooled fractions in water saturated porous media. The analysis is based on reactive chemical compounds whose hydrolysis reactions allow for accurate temperature measurements. The tracers are designed to improve geothermal reservoir management procedures. Thermo-sensitive tracers will provide valuable information about the thermal state of the examined permeable media. This is demonstrated by means of laboratory experiments with sand-packed columns. The special heating/cooling setup provides a defined internal temperature distribution. In 70 independent experiments, tracer sensitivity was examined. Practical limitations in three different experimental schemes, flow-through, moving thermal front and push–pull, were investigated. The results show that thermo-sensitive tracers can be used to measure temperatures and cooled fractions with high precision and accuracy.

Interannual variability of thermal front west of Luzon Island during the winter of 1993–2013 is examined with the method of singular value decomposition (SVD) and a suite of satellite measurements in this paper. It is found that both the area and intensity of the thermal front west of Luzon Island show apparent interannual variability. Further study based on SVD shows that the interannual variability of the thermal front is highly associated with El Nino and Southern Oscillation (ENSO), and the correlation coefficient between Nino3.4 index and the first Principal Component (PC1) of thermal front can reach–0.65. The mechanism can be described as follows. In El Nino (La Nina) years, the East Asian winter monsoon (EAWM) is weakened (enhanced), inducing weaker (stronger) local wind stress curl (WSC) west of Luzon Island, and resulting in weakened (enhanced) Luzon cold eddy, which finally leads to the weakening (enhancement) of the thermal front.

We carried out an integrated reservoir characterization to model a heavy oil reservoir called Balol located in the heavy oil belt of Mehsana in the western state of Gujarat in India. The Oil and Natural Gas Corporation of India was the field operator. The operator adopted in situ combustion process in northern part of Balol because of high-mobility contrast between oil and water. However, the performance review carried out by the operator found that oil recovery from this field was not as per prediction. Hence, serious attempts were made to interpret 3D seismic data to map the reservoir efficiently. We integrated the information derived from 3D time-lapse seismic data with the well logs provided by the operator to explain the movement of thermal front tracked using time-lapse seismic data. To model the reservoir, flow unit and electrofacies characterization was also carried out, and four to five FUs with conduits and baffles to flow were identified. Electrofacies analysis identified three major reservoir facies. These analyses also revealed that Balol reservoir was layered and heterogeneous with depth. Further, in addition to 3D seismic data, well logs and empirical equations were used to generate porosity, water saturation, and permeability models for the entire reservoir. Thus, a reservoir model with heterogeneous distribution of petrophysical properties was generated. We observed a high permeability trend in the northwest direction at injection wells, which could be governing the movement of thermal fronts in the reservoir.

Modern sea surface temperatures (SSTs) were estimated from UK′37 values of ten core-top sediment samples collected under the Cabo Frio upwelling system and validated by comparison with satellite-derived SSTs. UK′37-SSTs were found to reflect annual SST means in the offshore area and seasonal means (winter/spring) in the inshore and central areas. The latter areas are mainly influenced by upwelling processes whereas the offshore area is under the influence of the thermal front of the Brazil Current (BC). SST variability during the last century was then reconstructed from three short sediment cores. The record showed a general cooling trend in the inshore and central areas, suggesting intensification of the upwelling process. The trends at the offshore area reflected oscillations of the BC thermal front, with piling up of warmer BC waters closer to the coast since ca. 1950.

A mathematical model of the axisymmetric distribution of the phases in the zone of invasion of the water-based drilling mud into the productive stratum whose porous space can simultaneously contain three immiscible fluids (oil, gas, and natural water) is constructed; the model takes into account the high rate of heat transfer between the fluids and the rock matrix. It is shown that the resistivity of the invaded zone depends not only on saturation of the latter by the fluids and the concentration of salts in the water phase, but also on the drilling mud filtrate temperature. It is also shown that there is a jump in the function of stratum saturation by oil on the thermal front.

Two major temperature fronts, the Subpolar (Gosung, Gang-won-do; $38^{\circ}-41^{\circ}N$ ) and Thermal (Jukbyun, Gyeong-sang-buk-do; $36^{\circ}-37^{\circ}N$ ) fronts, are found in the East Sea along the east coast of Korea. These are located roughly where the Tsushima Warm Current and North Ko...

The primary mode of deactivation of automotive emission control catalysts is thermal aging, and it is well-known that high-temperature lean aging conditions are particularly detrimental. Since evaluating the long-term durability of automotive catalysts is costly and time-consuming, rapid catalyst aging cycles have been developed to mimic (in a reduced time) the catalyst deactivation under real-world driving conditions. One of the commonly used rapid catalyst aging tests is an exothermal aging cycle, which involves a combination of fuel-rich engine operation and supplemental air injection to generate high-temperature lean conditions within the catalyst bed. In this work, we use the previously developed transient three-way catalyst model to investigate the time evolution of the axial temperature profiles and exhaust air–fuel ratio (A/F) along the catalyst bed during the course of the exothermal rapid aging cycles. We find that the thermal front propagates downstream through the catalyst bed relatively slowly (compared to the concentration front) and this can limit the location within the catalyst bed and duration for high-temperature lean exposure. We also investigate how variations of some of the key system design and operating parameters can affect the extent and duration of high-temperature lean exposure. Finally, a simple analytical expression is developed which allows one to estimate the time it takes for the thermal front to travel through the catalyst bed. This time can be compared with the period of the lean A/F operation during the aging cycle to determine the location and duration of high-temperature lean exposure.

Reactive tracers have long been investigated as a means to measure geothermal temperature profiles and predict thermal breakthrough, but this method has only been used in practice to estimate an effective (or average) reservoir temperature. This means that spatial information about the temperature profile is lost, and a sequence of reactive tracer tests would need to be carried out at different times to track the thermal front. Advances in nanotechnology have made the use of nanoparticles as geothermal tracers feasible. Nanomaterials can be designed with a high degree of control over their response to temperature, which could enable them to provide more information than reactive solute tracers. Nanoreactors that prevent reaction of encapsulated reactants from occurring until a threshold temperature is reached are a promising candidate for use as geothermal temperature sensors. It is demonstrated through modeling that this could enable engineers to determine the location of temperature measurements to map the inter-well temperature profile at a given time. This could facilitate more accurate reservoir fracture geometry characterization and thermal breakthrough prediction.

A control strategy of flow reversal with hot gas withdrawal for heat recovery was developed and verified for the mitigation and utilization of ventilation air methane (VAM) in a reverse flow reactor. The flow reversal strategy was based on the thermal front propagation velocity and a logic-based controller was built to avoid catalyst deactivation and reaction extinction caused by prolonged rich or lean feed conditions; the utilization of heat released from VAM combustion was considered through heat extraction by withdrawing part of hot gas from the middle of the reactor. By means of simulation using a one-dimensional heterogeneous model, the results revealed that the flow direction should be reversed before the temperature peak passing through the middle of the reactor to reduce the discharge of unreacted methane as well as to enhance the heat recovery efficiency; a fixed (relatively short) switching time is reasonable for the reactor operation in the case of hot gas withdrawal. The stability and autothermicity of reverse flow reactor are jointly influenced by the feed concentration and hot gas withdrawal fraction; the reactor can only be run stably in a narrow operating window (stability area). Heat recovery and bed temperature regulation are achieved mainly by hot gas withdrawal, while air dilution and extra methane injection are the auxiliary manipulated variables to sustain the reaction in some extreme circumstances. An extra catalyst bed along the way to the boiler is effective to enhance the overall methane conversion by oxidizing the unreacted methane. A case study under modified real ventilation conditions shows that the control strategy developed in this work is feasible to mitigate and utilize VAM if the methane content is higher than 0.2 vol.%.

We use a continuum model of reservoir evolution to explore the interaction of coupled thermal, hydraulic and chemical processes that influence the evolution of seismicity within a fractured reservoir from stimulation to production. Events occur from energy release on seeded fractures enabling moment magnitude, frequency and spatial distribution to be determined with time. Event magnitudes vary in the range −2 to +2 with the largest event size (~2) corresponding to the largest fracture size (~500 m) and a prescribed stress drop of 9 MPa. Modelled b-values (~0.6–0.7) also correspond to observations (~0.7–0.8) for response in the Cooper Basin (Australia). We track the hydrodynamic and thermal fronts to define causality in the triggering of seismicity. The hydrodynamic front moves twice as fast as the thermal front and envelops the triggered seismicity at early time (days to month) – with higher flow rates correlating with larger magnitude events. For later time (month to years), thermal drawdown and potentially chemical influences principally trigger the seismicity, but result in a reduction in both the number of events and their magnitudes.

As we all know, the Earth is a watery place. About 71 % of the planet’s surface is covered with water, and the oceans contain approximately 96.5 % of all Earth’s water. The oceans influence almost all aspects of life on Earth, making it vital to understand their role in the global context. Let us remember that life itself originated in the oceans! First of all, our oceans play a major role in influencing changes in the world’s climate and weather.

Theoretical investigation of the dynamics of free thermal plumes in a thin vertical layer has been performed for the case of a cavity heated from below by means of a dotted thermoelement. Three-dimensional numerical modeling has been carried out with the help of package OpenFOAM. This integrable platform is meant for calculations in the area of continuous media mechanics. Four basic plume growth types (viscous-diffusive, inviscid-diffusive, viscous-nondiffusive and inviscid-nondiffusive regimes) are found. Animated images for various lifting regimes are obtained to observe the time-dependent behavior of thermal plumes. The stages of plume formation in a relatively thin layer, its steady lifting and deceleration by the top boundary have been analyzed for different profiles of the plume front. The interaction of two synchronous plumes is studied numerically, and the formation of a common thermal front is demonstrated.

Sea surface temperature is one of the important parameters in determining the area of fishing ground. On the sea surface temperature the events of thermal fronts and upwelling can be observed visually by processing satellite imagery data. Generally, the fishing ground is determined visually by the human operator through direct observation on the monitor (called visualization approach). However, visualization approach is very subjective and labor-intensive. In this study, we focused in determining the upwelling and thermal-front. A new approach is proposed, by extracting the feature from satellite imagery data and using contour matching, can be determined whether the events of thermal fronts and upwelling have occurred. With this approach the process of visualization is not needed anymore because the computer can determine the location of the upwelling and thermal fronts without human operator intervention.

Ocean colour and thermal data from earth orbiting satellites are being used in fishery resource applications. The location of ocean fronts and circulation features are considered as prospective fishing grounds. Ocean frontal zones, as resolved by strong gradients in the surface temperature distribution, has historically been important as indicators for fishing localities over all the oceans. In the present study, the sea surface temperature and chlorophyll concentration map along with the primary productivity map are used to evaluate the usefulness of the above data in fishery forecasting. In the present study, North Andhra Fishing Zone and Maharastra Fishing Zone, India have been taken for investigation. The analysis of thermal front, chlorophyll front with fish catch indicates a nonlinear relationship. The analysis of sea surface temperature (SST) with fish catch also shows a nonlinear relationship. The analysis of chlorophyll concentration with fish catch shows a linear relationship. However, the coefficient of determination (r2) in each case is found to be inconsistent between the two fishing zones. The analysis of primary productivity front with fish catch shows a non linear relationship. The analysis of primary productivity and fish catch shows a linear relationship. The r2 values in both the cases are found to be closer to each other between the two fishing zones. Therefore, it is suggested to include primary productivity map for improved fishing forecasting.

The subsatellite experiment “Thermal Front in Lake Ladoga, 2010” and its results are described. The experiment was performed at the initial stages of thermal bar existence at the end of May 2010. We estimated the horizontal gradients of water temperature and the front motion rate by two successive surveys carried out with a discreteness of four days. Cumulative heat flows coming to the lake surface were different on different front sides. The hydrochemical and hydrobiological parameters of the front zone were not characterized by any significant horizontal differences.

The manifestation in the Baltic Sea of a seasonal, structural, thermally-induced front (a direct analogue of the lacustrine thermal bar) and its specific features after winters of different severity are examined. Analysis of long-term, spring-period, monthly mean SST data reveals that surface water temperatures first exceed the (salinity-dependent) temperature of maximum density (Tmd) in the southern part of the Baltic Sea. This phenomenon advances northwards at a speed of about 11 to 16 km d–1, traversing the breadth of the sea within 8 to 10 wk. Surface temperature measurements across the Tmd-isotherm demonstrate that after the severe winter of 2002-2003 the frontal zone was highly pronounced, with a horizontal temperature gradient 10 to 100 times as large as the long-term monthly mean equivalent. Although the horizontal gradient was smaller after the mild winter of 20062007, it was still 10 times as large as the long-term monthly mean gradient. A clear correlation of thermal front advancement with biological parameters is revealed: an area of elevated chlorophyll a (about 200 km in width) associated with the Tmd was observed after severe winters, with the characteristic life-time of this zone 1 mo longer than that occurring after mild winters.

Airborne hyperspectral and thermal infrared imagery collected over the Florida Current provide a view of the disintegration of a Sargassum drift line in 5 m s −1 winds. The drift line consists mostly of rafts 20–80 m 2 in size, though aggregations larger than 1000 m 2 also occur. Rafts tend to be elongated, curved in the upwind direction, and 0.1–0.5 °C warmer than the surrounding ocean surface. Long weed ‘trails’ extending upwind from the rafts are evidence of plants dropping out and being left behind more rapidly drifting rafts. The raft line may be a remnant of an earlier Sargassum frontal band, which is detectible as an upwind thermal front and areas of submerged weed. Issues are identified that require future field measurements.

An exact integral solution for transient temperature distribution, due to injection-production, in a heterogeneous porous confined geothermal reservoir, is presented in this paper. The heat transport processes taken into account are advection, longitudinal conduction and conduction to the confining rock layers due to the vertical temperature gradient. A quasi 2D heat transport equation in a semi-infinite porous media is solved using the Laplace transform. The internal heterogeneity of the geothermal reservoir is expressed by spatial variation of the flow velocity and the effective thermal conductivity of the medium. The model results predict the transient temperature distribution and thermal-front movement in a geothermal reservoir and the confining rocks. Another transient solution is also derived, assuming that longitudinal conduction in the geothermal aquifer is negligible. Steady-state solutions are presented, which determine the maximum penetration of the cold water thermal front into the geothermal aquifer.

Seven years (January 2000 to December 2006) of AVHRR and SeaWiFS data were used to estimate monthly climatological means and to present SST and chlorophyll-a seasonal evolution in San Matias Gulf, located between 40° 47' S and 42° 13' S on the Argentine coast. SST and chlorophyll-a satellite maps corresponding to spring-summer showed two well differentiable sectors: the southern zone presented colder waters and higher chlorophyll-a concentration while the northern one showed warm water and lower chlorophyll-a. Hake (Merluccius hubbsi) is the most important resource in terms of landings and economic revenues of the San Matias Gulf. Fishing activity data gathered by a Vessel Monitoring System (2004-2006) were linked with SST and chlorophyll-a maps showing that the fishing vessels operated on the thermal front from November to March and had the maximum hake yields. In addition, AVHRR-SST and SeaWiFS-chlorophyll-a data were compared with temperature and chlorophyll-a measured in oceanographic surveys carried out in 2007.

Sea surface temperature (SST) data from S-NPP VIIRS satellite has different spatial resolution with SST data from Himawari-8 satellite. In this study comparative analysis of potential fishing zones information from both satellites has been conducted. The analysis was conducted on three project areas (PA 7, PA 13, PA 19) as a representation Indonesian territorial waters. The data used were daily for both satellites with a period time from August 2016 to December 2016. The method used was Single Image Detection (SIED) to detect thermal fronts. Method of mass center point for determining potential fishing zones coordinate point from result thermal front detection. Furthermore, an analysis of overlapping was done to compare the coordinate point information from both satellites. Based on data analysis that had been done, the result showed that potential fishing zones coordinate points of Himawari-8 satellite was mostly far from potential fishing zones coordinate point of S-NPP VIIRS. The coordinate points whose positionswere close together or nearly same from both satellites was only about 20 %. Differences in potential fishing zones coordinate positions occur due to the effect of different spatial resolutions of both satellite data and the size of the front thermal events that had high variability. The ideal potential fishing zones coordinate points information was probably a combination of the potential fishing zones coordinate points of S-NPP VIIRS and Himawari-8 by making two adjacent coordinate points to be a single coordinate point. Field validation testing was required to prove the accuracy of the coordinate point.

Marine predators are thought to utilise oceanic features adjusting their foraging strategy in a scale-dependent manner. Thus, they are thought to dynamically alter their foraging behaviour in response to environmental conditions encountered. In this study, we examined the foraging behaviour of King Penguins (Aptenodytes patagonicus) breeding at South Georgia in relation to predictable and stable oceanographic features. We studied penguins during their long post-laying foraging trips during December 2005 and January 2006. For this investigation, we undertook a simultaneous analysis of ARGOS satellite-tracking data and Mk 7 Wild Life Computers Time Depth Recorder (TDR) dive data. To investigate correlations between foraging behaviour and oceanographic conditions, we used SST data from January 2006 from MODIS satellite AQUA. To determine changes in search effort, first passage time (FPT) was calculated; for analysis of dive behaviour, we used several dive parameters that are thought to be reliable indicators of changes in foraging behaviour. King Penguins appeared to target predictable mesoscale features in the Polar Front Zone (PFZ), either a warm-core eddy in the PFZ or regions of strong temperature gradients at oceanic fronts. Two different trip types could be distinguished: direct trips with a straight path to one foraging area at the edge of an eddy or at a thermal front, and circular trips where birds foraged along strong thermal gradients at the northern limit of the PFZ. It is likely that both trip types were a direct consequence of prey encounter rates and distributions, both of which are likely to be associated with these oceanographic features. Circular trips often included passages across the centre of an eddy where birds made deep foraging dives, but remained only a short time in the eddy, possibly because prey were too deep. All birds showed Area Restricted Search (ARS) at scales of

The national scale of Indonesian Potential Fishing Zone (PFZ) forecast system has been established since 2000. Recent times this system use Single Image Edge Detection algorithm to automatically identify thermal front from remote sensing images. Its generate two fishing ground/FG criteria: FG (high probability) and potential fishing ground/PFG (medium/low probability). To quantify the accuracy of this algorithm, an experimental fishing/EF was carried out in Tolo Bay, Central Sulawesi Province at September 2016 the late southeast monsoon period by using a pole and line fishing vessel. Four fishing activities (P1, P2, P3, and P4) were conducted during this study at a different location nearby the PFZ forecast position, two of them had good results. Based on distance measurement, these locations P1 and P4 were associated with PFZ forecast position. They were associated with PFG and FG criteria. The distance between EF to P1 and P4 were 9.7 and 6.69 nautical miles. The amount of catch for each location was 850 and 900 kg, respectively. The other locations P2 and P3 were also associated with PFG criteria, but there was no catch. We conclude that the number of the catch is influenced by the distance from PFZ forecast position and criteria.

An N-shape thermal front in the western South Yellow Sea (YS) in winter was detected using Advanced Very High Resolution Radiation (AVHRR) Sea Surface Temperature data and in-situ observations with a merged front-detecting method. The front, which exists from late October through early March, consists of western and eastern wings extending roughly along the northeast-southwest isobaths with a southeastward middle segment across the 20-50 m isobaths. There are north and south inflexions connecting the middle segment with the western and eastern wings, respectively. The middle segment gradually moves southwestward from November through February with its length increasing from 62 km to 107 km and the southern inflexion moving from 36.2A degrees N to 35.3A degrees N. A cold tongue is found to coexist with the N-shape front, and is carried by the coastal jet penetrating southward from the tip of the Shandong Peninsula into the western South YS as revealed by a numerical simulation. After departing from the coast, the jet flows as an anti-cyclonic recirculation below 10 m depth, trapping warmer water originally carried by the compensating Yellow Sea Warm Current (YSWC). A northwestward flowing branch of the YSWC is also found on the lowest level south of the front. The N-shape front initially forms between the cold tongue and warm water involved in the subsurface anti-cyclonical recirculation and extends upwards to the surface through vertical advection and mixing. Correlation analyses reveal that northerly and easterly winds tend to be favorable to the formation and extension of the N-shape front probably through strengthening of the coastal jet and shifting the YSWC pathway eastward, respectively.

We report the first study of the gas generation and thermal wave behavior during the performance of the novel nanoenergetic system based on aluminum and iodine pentoxide nanoparticles. The homogeneous mixture of Al/I2O5 ignited in the range of 605–620 °C and generated a thermal front that propagated through the sample with a velocity of ∼2000 m/s. The maximum peak pressure of up to 11 MPa (m = 0.5 g) was generated by a mixture containing ∼78 wt% of I2O5. The maximum pressure × volume PV-value for a 0.5 g sample was ∼3.8 kPa m3 is comparable to that generated by the same sample mass of the Bi2O3/Al system.

With the advent of horizontal wells, a distinct change is tacitly taking place in our approach to the improved recovery of heavy oil-from displacing mobilized oil in a flood pattern from injector to producers over long distances on the order of hundreds of metres to short-distance oil displacement (SDOD) processes (typically over a few tens of metres). SDOD processes comprise Steam Assisted Gravity Drainage (SAGD), Cyclic Steam Stimulation (CSS) and Toe-to-Heel (TTH) Displacement Processes, which comprise Toe-to-Heel Air Injection (THAI), with its variant catalytic THAI (CAPRI), and Toe-to-Heel Waterflooding (TTHW). Presently SAGD is commercially used, while THAI has been under field testing for 3 years; testing of CAPRI is scheduled to start in 2010. TTHW has been under field testing both in the US and Canada for more than 4 years. Steamflooding in a TTH configuration (TTH steamflooding) uses vertical wells as injectors and horizontal wells as producers, arranged in a staggered line drive, with producers having their toes close to the shoes of vertical injectors; the horizontal section of producers is located at the base of the pay. The vertical wells are used for initiating the steam front, which subsequently is anchored at the toe of the horizontal producer; it is then propagated towards the producer's heel. In TTH steamflooding, the existing deficiency of conventional steamflooding schemes in terms of low vertical sweep is overcome by the beneficial use of gravity. To investigate the potential of TTH steamflooding, some laboratory tests were conducted. The objective was to assess the feasibility of TTH steam and thermo-solvent flooding (steam+propane co-injection) by carrying out 3D model experiments using heavy oil with a viscosity of 15,000 cP. Laboratory results showed that the concepts of TTH steamflooding and TTH steamflooding with solvent are feasible. All in all, stability of TTH steamflooding was relatively good, while the stability of TTH steamflooding with the addition of nitrogen or propane was much better. Significant improvements in design and operation of these processes were needed in order to promote override during the early phase, and obtain a stable and efficient process. The improvements included a cold (gas fingering) and a hot (steam-based) communication phase-, and controlling lateral spread of steam by using two additional vertical control wells (positioned laterally but close to the heel of the horizontal producer) for conducting a limited steamflood. Nitrogen was injected along with steam in the conventional steamflood; propane replaced nitrogen in TTH steamflooding with solvent. With these improvements, rise of steam chamber to the top occurred much earlier, and a favourable tilt-forward-angle of the thermal front was quickly obtained. TTH steamflooding with solvent proved superior to the TTH steamflooding, as the channeling of steam through the horizontal well was much better controlled, and the oil recovery was considerably faster. With these improvements, the oil recovery increased from 50 - 54% to 75 - 77%, and the operation became smoother. Presently, the process can be considered only for reservoirs where oil has some mobility under reservoir conditions. In order to develop the full potential of TTH steamflooding, technology means are needed for controlling channeling through the horizontal producer (this control Occurs naturally in the THAI process); at present there are a few methods which seem promising.

Seasonal upwelling variations are examined in the eastward coastal boundary branches of the Tsushima Warm Current (TWC). The climatological pattern and the fundamental hydrographic structure of the seasonal appearance of cold water are revealed by analyzing the temperature profile data around the Japanese shelf area. Seasonal maps of temperature at the intermediate layer around 200 m depth show the rise of the main pycnocline along the Japanese coast due to seasonal subsurface cooling from May to September. The cold water areas appear around the strong curvature in the continental shelf break. These areas are confined to the south of the TWC thermal front, i.e., to the coastal boundary region. The seasonal appearance of the localized cooling areas implies that the seasonal upwelling is induced by horizontal variations in shelf topography and the intensifying TWC from May to September.

All flue gases contain water vapour along with carbon dioxide, nitrogen, etc. Vacuum Swing Adsorption (VSA), which has been successfully studied for post-combustion dry CO2 capture in our group, is strongly affected by the overwhelming competitive adsorption of water vapour on CO2 adsorbents. In this study, breakthrough experiments have been conducted to measure the single/binary adsorption isotherm data of CO2 and water vapour on zeolite 13X and a proprietary alumina-based adsorbent alumina CDX to study the competitive adsorption effect on each other. The CO2 adsorption data are well represented by the Dual site Langmuir isotherm equation. Based on the above understanding, a single column multilayered VSA unit was used with a guard-bed layer of superior desiccant and a main layer of 13X to simultaneously remove water (3–4% by volume) and capture CO2 (10–12%) at 30 ∘C within the same process. In this study, activated alumina CDX was selected as the appropriate pre-layer. Furthermore, we have investigated the effects of operating parameters on the multilayered CO2/H2O VSA performance. The water front was accurately located in the bed and the interaction of CO2 and water vapour indicates a clear indication of a water loaded zone and a CO2 loaded zone. The result demonstrates that water front has been successfully held in the pre-layer and CO2 product purity of 76.9% and purity of 67% were achieved for the double layered single column CO2/H2O VSA.