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Argo剖面浮标已成为海洋溶解氧观测数据的主要来源,截至2018年7月已在全球范围内获取了超过13万条溶解氧剖面,然而目前其数据的质量控制仍然存在不足。本文首先介绍了Argo浮标上携带的溶解氧传感器的测量原理、主要误差来源以及两种校正方法:气候态校正法与空气测量校正法,并提出了目前在溶解氧传感器数据质量控制研究亟需解决的技术问题,包括:①由于传感器伸出水面的高度不够,一些浮标并不能有效测量空气氧含量,因为无法进行空气测量校正方法;②Argo观测的溶解氧数据库中目前存在一些异常测量剖面没有得到有效剔除,影响校正系数的计算;③使用平均值确定校正系数的方法容易受到异常剖面的干扰。 相似文献
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参考数据集对Argo剖面浮标盐度观测资料校正的影响 总被引：4，自引：0，他引：4
国际Argo计划采用新颖的Argo剖面浮标来监测全球大洋中上层的变化,对浮标盐度观测资料进行质量控制是非常重要的。本文采用历史水文观测资料集得到的温-盐度(-S)关系,并利用Wong等人开发的WJO延时模式盐度校正方法,对电导率传感器出现漂移、偏移等故障的Argo剖面浮标盐度资料进行校正。对影响校正结果的历史水文资料集(或参考数据集)的选取进行了初步研究,并在不同的海区进行试验。结果表明,选取合适的参考数据集可以提高盐度校正的精度。 相似文献
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《中国海洋大学学报(自然科学版)》2021,(8)
本文利用涡旋内温度异常剖面对黑潮延伸体区域的涡旋进行分类与分析。基于卫星高度计识别的涡旋数据和与涡旋时空匹配的Argo浮标温度异常剖面数据,本文提出了一种优化的高斯混合模型无监督聚类方法实现涡旋内Argo浮标温度异常剖面的自动聚类,进而实现与剖面时空匹配涡旋的自动分类。实验结果表明,相同类型的Argo温度异常剖面呈现出明显的空间聚集效应,而不同类型的Argo温度异常剖面则在空间上相互分离,与表层(次表层)温度异常剖面相匹配的涡旋主要分布在黑潮延伸体的北部(南部)。相较于直接利用区域范围对涡旋进行分类的方法,本文所提出的涡旋分类方法更为客观,合成分析特定类型涡旋的水下结构也更为合理。 相似文献
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Argo光盘数据集的研制与应用 总被引：1，自引：1，他引：0
早期的Argo数据光盘主要基于文件系统的数据管理,都没有提供对查询结果的保存和打印功能,更没有引入数据库系统对浮标数据进行综合管理.文中针对Argo数据共享和分发过程中存在的不足,特别是Argo光盘数据集所存在的问题,提出了改进方法.并引进数据库技术对Argo光盘数据集进行了补充和完善:提出了使用Winrar压缩软件对光盘数据资料进行压缩,从而解决了日益增加的Argo数据与光盘容量有限的矛盾,可以更好的满足Argo数据分发和共享的需求.为了充分发挥Argo光盘数据集的功能,文中还针对Argo资料用户对图形文件的需求,利用VC++和Matlab混合编程的方法,开发了Argo视图软件.最后,基于数据库技术研制完成了一张包含了1997-2006年全球海洋上全部Argo剖面浮标观测的Argo光盘数据集,并系统介绍了该数据集的结构、功能和应用过程等. 相似文献
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HM2000 型剖面浮标是一种新颖的国产海洋观测仪器,可以长期在海上自由漂移并连续测量 0~2 000 m 水深内的海水温、盐度剖面数据,已被国际 Argo 组织用于全球 Argo 实时海洋观测网建设和维护。 详细介绍了该型浮标的工作原理、结构、功能和主要技术指标等,并与 APEX 型浮标进行了比较分析, 表明了 HM2000 型剖面浮标具有明显的功能优势,且测量的温、盐度质量是有足够保证的,完全可以替代国外浮标用来主导建设我国的 Argo 区域海洋观测网。 相似文献
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Argo-认识和预测气候变化的全球海洋观测计划 总被引：1，自引：2，他引：1
1 全球海洋观测网 (Argo)为了解全球气候的变化 ,海洋学界正在做一项雄心勃勃的事业 ,即设计并部署一个全球海洋观测系统 ,以便对海洋从季节到十年间的变化作前所未有的长期跟踪观测。这项计划的实施 ,将使人类对气候的认识和预测向前迈出一大步。全球海洋观测系统的现场支柱就是 Argo剖面浮标网 ,将为人类提供一个全球海洋次表层数据库。Argo剖面浮标观测网将由 3 0 0 0个自动仪器组成 (图 1 ) ,每个浮标每隔 1 0天发送一组取自 2 0 0 0 m到海面的温度和盐度剖面资料 (图 2、3 )。在全球大洋内每隔大约 3个经纬度布设一个浮标 ,其数据通… 相似文献
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基于Argo浮标的热带印度洋混合层深度季节变化研究 总被引：2，自引：0，他引：2
根据2004-2005年热带印度洋(30°S以北)的Argo浮标(自持式海洋剖面观测浮标)温度-盐度剖面观测资料,采用位势密度判据(Δσθ=0.03 kg/m3),针对每个Argo浮标的温度-盐度观测剖面确定了海洋混合层的深度,然后采用Krig插值方法构建了3°×3°空间分辨率的月平均网格化混合层深度产品。通过与已有气候平均混合层深度资料的比较表明了该产品的合理性,在此基础上进一步对热带印度洋海盆尺度的混合层深度空间特征和季节变化规律进行了讨论。研究结果表明,Argo浮标资料可用于热带印度洋混合层变化的研究,为进一步研究热带印度洋海-气相互作用提供了基础资料。 相似文献
11.
潮汕坳陷多次波组合压制技术研究 总被引：1，自引：0，他引：1
潮汕坳陷中生界发育,是我国海上重要的油气勘探后备区。但该区多次波非常发育,多次波识别和压制一直是该区地震资料处理的关键和难点。合理地选取有效的多次波压制方法是获得高品质地震剖面的关键所在。针对原始资料中多次波异常发育的情况,文章分析了该区多种类型多次波的特点,尝试了零偏移距截距时间-射线参数(τ-p)域预测反褶积、自由界面多次波衰减法(Surface-Related Multiple Elimination,SRME)和双曲线Radon变换,对多次波进行组合压制,克服了仅依靠一种手段难以压制多种类型多次波的局限。从资料处理效果看,τ-p域预测反褶积方法对短周期的鸣震和微曲多次波的压制效果较好,SRME有效地压制自由表面多次波,且在近炮检距范围内压制多次波效果很好,而双曲线Radon变换是衰减长周期的层间多次波和未被充分压制的自由表面多次波很好的选择。组合压制多次波后的剖面质量明显得到改善。 相似文献
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A monthly mean climatology of the mixed layer depth (MLD) in the North Pacific has been produced by using Argo observations.
The optimum method and parameter for evaluating the MLD from the Argo data are statistically determined. The MLD and its properties
from each density profile were calculated with the method and parameter. The monthly mean climatology of the MLD is computed
on a 2° × 2° grid with more than 30 profiles for each grid. Two bands of deep mixed layer with more than 200 m depth are found
to the north and south of the Kuroshio Extension in the winter climatology, which cannot be reproduced in some previous climatologies.
Early shoaling of the winter mixed layer between 20–30°N, which has been pointed out by previous studies, is also well recognized.
A notable feature suggested by our climatology is that the deepest mixed layer tends to occur about one month before the mixed
layer density peaks in the middle latitudes, especially in the western region, while they tend to coincide with each other
in higher latitudes. 相似文献
13.
一种利用SMOS卫星观测的海表面盐度反演海水盐度廓线的方法 总被引：4，自引：1，他引：3
This paper proposes a new method to retrieve salinity profiles from the sea surface salinity(SSS) observed by the Soil Moisture and Ocean Salinity(SMOS) satellite. The main vertical patterns of the salinity profiles are firstly extracted from the salinity profiles measured by Argo using the empirical orthogonal function. To determine the time coefficients for each vertical pattern, two statistical models are developed. In the linear model, a transfer function is proposed to relate the SSS observed by SMOS(SMOS_SSS) with that measured by Argo, and then a linear relationship between the SMOS_SSS and the time coefficient is established. In the nonlinear model, the neural network is utilized to estimate the time coefficients from SMOS_SSS, months and positions of the salinity profiles. The two models are validated by comparing the salinity profiles retrieved from SMOS with those measured by Argo and the climatological salinities. The root-mean-square error(RMSE) of the linear and nonlinear model are 0.08–0.16 and 0.08–0.14 for the upper 400 m, which are 0.01–0.07 and 0.01–0.09 smaller than the RMSE of climatology. The error sources of the method are also discussed. 相似文献
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A new method to identify the foot of continental slope based on an integrated profile analysis 总被引：2，自引：0，他引：2
Ziyin Wu Jiabiao Li Shoujun Li Jihong Shang Xiaobin Jin 《Marine Geophysical Researches》2017,38(1-2):199-207
A new method is proposed to identify automatically the foot of the continental slope (FOS) based on the integrated analysis of topographic profiles. Based on the extremum points of the second derivative and the Douglas–Peucker algorithm, it simplifies the topographic profiles, then calculates the second derivative of the original profiles and the D–P profiles. Seven steps are proposed to simplify the original profiles. Meanwhile, multiple identification methods are proposed to determine the FOS points, including gradient, water depth and second derivative values of data points, as well as the concave and convex, continuity and segmentation of the topographic profiles. This method can comprehensively and intelligently analyze the topographic profiles and their derived slopes, second derivatives and D–P profiles, based on which, it is capable to analyze the essential properties of every single data point in the profile. Furthermore, it is proposed to remove the concave points of the curve and in addition, to implement six FOS judgment criteria. 相似文献
16.
渤海沿岸固定冰粗糙特征的实测研究 总被引：1，自引：0，他引：1
The surface roughness characteristics(e.g., height and slope) of sea ice are critical for determining the parameters of an electromagnetic scattering, a surface emission and a surface drag coefficients. It is also important in identifying various ice types, retrieval ice thickness, surface temperature and drag coefficients from remote sensing data. The point clouds(a set of points which are usually defined by X, Y, and Z coordinates that represents the external surface of an object on earth) of land fast ice in five in situ sites in the eastern coast Bohai Sea were measured using a laser scanner-Trimble GX during 2011–2012 winter season. Two hundred and fifty profiles selected from the point clouds of different samples have been used to calculate the height root mean square, height skewness, height kurtosis, slope root mean square, slope skewness and slope kurtosis of them. The root mean square of the height, the root mean square of the slope and the correlation length are about 0.090, 0.075 and 11.74 m, respectively. The heights of 150 profiles in three sites manifest the Gaussian distribution and the slopes of total 250 profiles distributed exponentially. In addition, the fractal dimension and power spectral density profiles were calculated. The results show that the fractal dimension of land fast ice in the Bohai Sea is about 1.132. The power spectral densities of 250 profiles can be expressed through an exponential autocorrelation function. 相似文献
17.
Algorithm and validation of sea surface temperature observation using MODIS sensors aboard terra and aqua in the western North Pacific 总被引：4，自引：0，他引：4
Kohtaro Hosoda Hiroshi Murakami Futoki Sakaida Hiroshi Kawamura 《Journal of Oceanography》2007,63(2):267-280
A regional algorithm to estimate SST fields in the western North Pacific, where small oceanographic disturbance are often
found, has been developed using Moderate Resolution Imaging Spectroradiometers (MODIS) aboard Terra and Aqua. Its associated
algorithm, which includes cloud screening and SST estimation, is based on an algorithm for the Global Imager (GLI) aboard
Advanced Earth Observing Satellite-II (ADEOS-II) and is tuned for MODIS sensors. For atmospheric correction, we compare Multi-Channel
SST (MCSST), Nonlinear SST (NLSST), Water Vapor SST (WVSST) and Quadratic SST (QDSST) techniques. For NLSST, four first-guess
SSTs are investigated, including the values for MCSST, climatology with two different spatial resolutions, and near-real-time
objective analysis. The results show that the NLSST method using high-resolution climatological SST as a first-guess has both
good quality and high efficiency. The differences of root-mean-square error (RMSE) between the NLSST models using low-resolution
climatology and those using high-resolution climatology are up to 0.25 K. RMSEs of the new algorithm are 0.70 K/0.65 K for
daytime (Aqua/Terra) and 0.65 K/0.66 K for nighttime, respectively. Diurnal warming and the stratification of the ocean surface
layer under low wind are discussed. 相似文献
18.
Marie Tharp 《Marine Geodesy》2013,36(1):63-65
Mixed layer depth (MLD) is an important parameter in the study of air‐sea interaction, acoustic propagation, and fisheries. With the onset of the southwest monsoon, a jetlike surface water flow develops from west to east along the equatorial Indian Ocean (EIO) creating an upward west to east sea surface slope. This in turn creates a slope in MLD in the opposing direction. In this paper, emphasis is placed on obtaining monthly coefficients between MLD and sea level for three regions across the EIO. Using these coefficients, MLD has been estimated from Geosat altimeter data. MLD in this region has been computed with an RMS error of 16 m, from altimeter data, as verified by TOGA in situ profiles. 相似文献
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神舟四号高度计波形数据预处理和信息提取 总被引：1，自引：0，他引：1
神舟四号(SZ-4)高度计在国内首次提供了星载雷达高度计回波波形数据.本文中作者分析了SZ-4高度计回波波形的特点,完成波形数据的预处理,并在此基础上完成初步的信息提取.在数据预处理方面,通过SZ-4高度计水陆边界处波形的特点,提出了波形最大幅度控制的方法,筛选回波波形.在波形归一化处理过程中,发现SZ-4高度计波形中存在双峰现象,并指出第二个峰为异常波形区.在波形信息提取方面,利用波形重新跟踪得到的半功率点计算出SZ-4高度计高度跟踪补偿误差,并根据高度计天线指向角和回波波形下降沿斜率之间的关系,从波形后沿提取天线指向角信息.分析结果表明,SZ-4高度计天线指向比较平稳,而跟踪补偿由于变化较大,在计算海面高度时,应作为一项误差源被考虑到. 相似文献
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基于气候性温盐关系模型对Argo数据进行质量控制的研究 总被引：1，自引：0，他引：1
通过全球Argo计划的实施，我们获得了大量的温盐剖面数据。如果对浮标所在洋区的状况不是很了解，很难判断Argo浮标电导率传感器的工作状态及盐度数据的可靠性。为了避免错误的数据，必须对Argo进行有效的质量控制。国家海洋信息中心根据西北太平洋海区的南森站和CTD温盐数据，建立了高质量的气候学温盐数据集，对投放在西北太平洋海区的Argo浮标数据进行了相应的质量控制。结果表明，利用Argo浮标所在海区的气候学数据对Argo数据进行质控是比较有效的方法之一。 相似文献