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Long-term Sensor Drift Found in Recovered Argo Profiling Floats 总被引:5,自引:0,他引:5
We recovered three Argo profiling floats after 2 to 2.5 years of operation, and recalibrated their temperature, conductivity, and pressure sensors. The results demonstrate that these floats exhibited a significant drift in salinity of −0.0074 to −0.0125, primarily due to the conductivity sensor drift. Combined with the recalibration result for another previously recovered float, the indication is that the negative salinity drift increases nearly in proportion to the operating period of floats. The increasing rate is −0.0041 (±0.0015) year−1, which yields a salinity drift of −0.016 (±0.006) for the expected float lifetime of four years. The present result suggests that reducing the float surfacing time would improve the accuracy of the salinity measurements. 相似文献
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Takushi?NikiEmail author Taiki?Fujinaga Mariyo?F.?Watanabe Junji?Kinoshita 《Journal of Oceanography》2004,60(5):913-917
Solid-phase microextraction (SPME) is a simple, sensitive and less destructive method for the determination of dimethylsulfide
(DMS) in seawater. Combined with detection by gas chromatography-mass spectrometry (GC-MS), the method had sufficient sensitivity
(minimum detectable concentration of DMS was 0.05 nM), and practical levels of reproducibility (relative standard deviation
≤7%) and linearity (r
2 > 0.995) over a wide concentration range (0.5 to 910 nM). The protocol developed was applied to a Sagami Bay water sample
to determine concentrations of DMS and DMSP, and in situ DMSP-lyase activity. 相似文献
76.
Eddy Shedding from the Kuroshio Bend at Luzon Strait 总被引:16,自引:1,他引:16
TOPEX/POSEDIENT-ERS satellite altimeter data along with the mean state from the Parallel Ocean Climate Model result have been used to investigate the variation of Kuroshio intrusion and eddy shedding at Luzon Strait during 1992–2001. The Kuroshio penetrates into the South China Sea and forms a bend. The Kuroshio bend varies with time, periodically shedding anticyclonic eddies. Criteria of eddy shedding are identified: 1) When the shedding event occurs, there are usually two centers of high Sea Surface Height (SSH) together with negative geostrophic vorticity in the Kuroshio Bend (KB) area. 2) Between the two centers of high SSH there usually exists positive geostrophic vorticity. These criteria have been used to determine the eddy shedding times and locations. The most frequent eddy shedding intervals are 70, 80 and 90 days. In both the winter and summer monsoon period, the most frequent locations are 119.5°E and 120°E, which means that the seasonal variation of eddy shedding location is unclear. 相似文献
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In this paper we analyze seismic regime and earthquake depth distribution and correlation of seismicity and mud volcanism in the Azerbaijan and the Caspian Sea region. For the present region we have calculated accurate source locations, seismic activity, earthquake repetition and released earthquake energy parameters. It is shown that the active tectonic processes in the region are concentrated within the thick sedimentary cover that we consider as a general source of contemporary stress and a main structural element responsible for the origin of regional earthquakes. The correlation of seismicity and mud volcanism is of paragenetic character. 相似文献
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南海北部陆缘地壳结构探测结果分析 总被引:29,自引:4,他引:29
深部地震和重力资料反演揭示了南海北部陆缘地壳结构在总体上由北部的华南沿海(厚约30km)向南部的洋盆(5──8km)逐渐减薄。南海的近SN向拉张不仅造成南北方向地壳结构的巨大变化,也造成东西向的明显变化。在南海北部陆缘的西部,局部拉张产生了一系列裂谷构造。西沙海槽作为一条狭窄的陆内裂谷向西延伸,海槽南北两侧地壳厚度超过25km,海槽中部地壳减薄至不足10km。西端的莺歌海盆地地壳厚仅5km,缺少明显的壳内反射-折射。在珠江口盆地中部,地壳厚度在下陆坡明显减薄,地壳下部存在较薄的(3──4km)高速层(地震波速7.2──7.5km·s-1);在珠江口盆地东部,地壳底部存在约 10km厚、300km宽的高速层。在台湾地区,由于弧陆碰撞,曾经减薄的陆壳在碰撞带增厚,莫霍面深度超过30km。南海北部陆缘在裂谷拉张和海底扩张期间岩浆活动平静,表明南海北部陆缘为非火山型陆缘。 相似文献
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