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61.
This study investigated the changes in concentrations of haloacetic acids (HAAs) and haloacetonitriles (HANs) as disinfection byproducts (DBPs) for differe 相似文献
62.
Park Sojung Choi Mansik Jang Dongjun Joe Dongjin Park Kyunggue 《Ocean Science Journal》2020,55(1):49-67
Ocean Science Journal - In this study, we investigated the spatial and temporal distribution and sources of dissolved and particulate heavy metals in Masan Bay, an area that for a long time has... 相似文献
63.
Kenneth R. Young 《Geographical review》2019,109(2):258-264
64.
Bhavya P. S. Min Jun-Oh Kim Min-Seob Jang Hyo Keun Kim Kwanwoo Kang Jae Joong Lee Jae Hyung Lee Dabin Jo Naeun Kim Myung Joon Kim Yejin Lee Junbeom Lee Chang Hwa Bae Hyeonji Yoo Hyeju Park Sanghoon Yun Mi Sun Lee Sang Heon 《Ocean Science Journal》2019,54(4):515-528
Ocean Science Journal - Investigations on marine N2 fixation have gained momentum since 1960s with eventual establishments of relevant methodologies to identify species involved and quantify the... 相似文献
65.
Review of recent findings on the water masses and circulation in the East Sea (Sea of Japan) 总被引:1,自引:0,他引:1
Kuh Kim Kyung-Il Chang Dong-Jin Kang Young Ho Kim Jae-Hak Lee 《Journal of Oceanography》2008,64(5):721-735
Recent findings on water masses, biogeochemical tracers, deep currents and basin-scale circulation in the East/Japan Sea,
and numerical modeling of its circulation are reviewed. Warming continues up to 2007 despite an episode of bottom water formation
in the winter of 2000–2001. Water masses have definitely changed since the 1970s and further changes are expected due to the
continuation of warming. Accumulation of current data in deep waters of the East/Japan Sea reveals that the circulation in
the East/Japan Sea is primarily cyclonic with sub-basin scale cyclonic and anticyclonic cells in the Ulleung Basin (Tsushima
Basin). Our understanding of the circulation of intermediate water masses has been deepened through high-resolution numerical
studies, and the implementation of data assimilation has had initial success. However, the East/Japan Sea is unique in terms
of the fine vertical structures of physical and biogeochemical properties of cold water mass measured at the highest precision
and their rapid change with the global warming, so that full understanding of the structures and their change requires in-depth
process studies with continuous monitoring programs. 相似文献
66.
67.
68.
Distribution and expression of gas seeps in a gas hydrate province of the northeastern Sakhalin continental slope, Sea of Okhotsk 总被引:1,自引:0,他引:1
Young Keun Jin Young-Gyun Kim Boris Baranov Hitoshi Shoji Anatoly Obzhirov 《Marine and Petroleum Geology》2011,28(10):1844-1855
Multidisciplinary surveys were conducted to investigate gas seepage and gas hydrate accumulation on the northeastern Sakhalin continental slope (NESS), Sea of Okhotsk, during joint Korean–Russian–Japanese expeditions conducted from 2003 to 2007 (CHAOS and SSGH projects). One hundred sixty-one gas seeps were detected in a 2000 km2 area of the NESS (between 53°45′N and 54°45′N). Active gas seeps in a gas hydrate province on the NESS were evident from features in the water column, on the seafloor, and in the subsurface: well-defined hydroacoustic anomalies (gas flares), side-scan sonar structures with high backscatter intensity (seepage structures), bathymetric structures (pockmarks and mounds), gas- and gas-hydrate-related seismic features (bottom-simulating reflectors, gas chimneys, high-amplitude reflectors, and acoustic blanking), high methane concentrations in seawater, and gas hydrates in sediment near the seafloor. These expressions were generally spatially related; a gas flare would be associated with a seepage structure (mound), below which a gas chimney was present. The spatial distribution of gas seeps on the NESS is controlled by four types of geological structures: faults, the shelf break, seafloor canyons, and submarine slides. Gas chimneys that produced enhanced reflection on high-resolution seismic profiles are interpreted as active pathways for upward gas migration to the seafloor. The chimneys and gas flares are good indicators of active seepage. 相似文献
69.
Jae-Ok Lee Kyung-Suk Cho Rok-Soon Kim Soojeong Jang Katsuhide Marubashi 《Solar physics》2018,293(9):129
To better understand geomagnetic storm generations by ICMEs, we consider the effect of substructures (magnetic cloud, MC, and sheath) and geometries (impact location of flux-rope at the Earth) of the ICMEs. We apply the toroidal magnetic flux-rope model to 59 CDAW CME–ICME pairs to identify their substructures and geometries, and select 20 MC-associated and five sheath-associated storm events. We investigate the relationship between the storm strength indicated by minimum Dst index \((\mathrm{Dst}_{\mathrm{min}})\) and solar wind conditions related to a southward magnetic field. We find that all slopes of linear regression lines for sheath-storm events are steeper (\({\geq}\,1.4\)) than those of the MC-storm events in the relationship between \(\mathrm{Dst}_{\mathrm{min}}\) and solar wind conditions, implying that the efficiency of sheath for the process of geomagnetic storm generations is higher than that of MC. These results suggest that different general solar wind conditions (sheaths have a higher density, dynamic and thermal pressures with a higher fluctuation of the parameters and higher magnetic fields than MCs) have different impact on storm generation. Regarding the geometric encounter of ICMEs, 100% (2/2) of major storms (\(\mathrm{Dst}_{\mathrm{min}} \leq -100~\mbox{nT}\)) occur in the regions at negative \(P_{Y}\) (relative position of the Earth trajectory from the ICME axis in the \(Y\) component of the GSE coordinate) when the eastern flanks of ICMEs encounter the Earth. We find similar statistical trends in solar wind conditions, suggesting that the dependence of geomagnetic storms on 3D ICME–Earth impact geometries is caused by asymmetric distributions of the geoeffective solar wind conditions. For western flank events, 80% (4/5) of the major storms occur in positive \(P_{Y}\) regions, while intense geoeffective solar wind conditions are not located in the positive \(P_{Y}\). These results suggest that the strength of geomagnetic storms depends on ICME–Earth impact geometries as they determine the solar wind conditions at Earth. 相似文献
70.
Daniel Ierodiaconou Alexandre C. G. Schimel David Kennedy Jacquomo Monk Grace Gaylard Mary Young Markus Diesing Alex Rattray 《Marine Geophysical Researches》2018,39(1-2):271-288
Habitat mapping data are increasingly being recognised for their importance in underpinning marine spatial planning. The ability to collect ultra-high resolution (cm) multibeam echosounder (MBES) data in shallow waters has facilitated understanding of the fine-scale distribution of benthic habitats in these areas that are often prone to human disturbance. Developing quantitative and objective approaches to integrate MBES data with ground observations for predictive modelling is essential for ensuring repeatability and providing confidence measures for habitat mapping products. Whilst supervised classification approaches are becoming more common, users are often faced with a decision whether to implement a pixel based (PB) or an object based (OB) image analysis approach, with often limited understanding of the potential influence of that decision on final map products and relative importance of data inputs to patterns observed. In this study, we apply an ensemble learning approach capable of integrating PB and OB Image Analysis from ultra-high resolution MBES bathymetry and backscatter data for mapping benthic habitats in Refuge Cove, a temperate coastal embayment in south-east Australia. We demonstrate the relative importance of PB and OB seafloor derivatives for the five broad benthic habitats that dominate the site. We found that OB and PB approaches performed well with differences in classification accuracy but not discernible statistically. However, a model incorporating elements of both approaches proved to be significantly more accurate than OB or PB methods alone and demonstrate the benefits of using MBES bathymetry and backscatter combined for class discrimination. 相似文献