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针对海岸带和海岛(礁)稀少地面控制区域控制条件不足和定位精度较低等情况,将水边线等高条件与有理函数模型(RFM)相结合,充分利用海岸带卫星影像的特点,将水边线等高点引入平差,提出了一种基于水边线等高的海岸带稀少地面控制卫星影像定位方法。实验结果表明,在同样稀少地面控制情况下,该方法与未加入等高控制条件的海岸带卫星影像定位方法相比,高程定位精度有了明显的提高;在离海岛较近的大陆岸边布设控制点,利用本文方法同样可以在海岛获取较高的定位精度。这对于稀少地面控制条件下海岸带、海岛(礁)地理信息的精确获取,具有重要意义。 相似文献
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为提升海岸带区域遥感影像无控定位能力,构建高精度海岸带数字表面模型(digital surface model, DSM),提出使用ICESat-2星载激光测高数据精化提取控制点,辅助自主可控高分遥感卫星影像立体区域网平差,从而提高影像定位精度。最后利用某海岸带区域高分七号卫星影像和提取制作的ICESat-2激光控制点进行海岸带数字表面模型构建试验,结果表明：使用上述方法构建的海岸带数字表面模型高程精度已满足1∶1万比例尺成图高程精度优于1.5 m的要求。本文方法对在海岸带或境外等地区开展遥感测绘具有借鉴意义。 相似文献
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针对无控制点条件下测绘卫星影像区域网平差迭代难以收敛和影像重叠区域存在接边误差的问题,提出了一种基于基准影像的区域网平差方法。利用资源三号卫星影像进行无控制点条件下的区域网平差时,相对于LEVENBERG MARQUARDT算法,基于基准影像的区域网平差方法能得到较为稳定的平差解和较好的平差精度。为进一步验证方法的适用性,利用异轨长条带天绘一号卫星影像数据进行无控制点条件下的区域网平差。实验结果表明,基于基准影像的区域网平差方法显著优化了卫星影像的内部符合精度,为下一级卫星测绘产品的高精度处理奠定了基础。 相似文献
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利用东印度洋海域周边长期验潮站实测数据、TOPEX/Poseidon等系列卫星测高反演结果,评估了DTU10,EOT11a,FES2014,GOT4.8,OSU12和TPXO8六种全球潮汐模型精度,根据卫星测高结果给出了浅水分潮改正量和长周期分潮改正量的经验模型,又在此基础上分析并构建了研究区域精度最优的深度基准面模型。考虑到全球潮汐模型在近岸的影响因素及验潮站位置,将13个验潮站分成开阔海域与近海海域两类,与潮汐模型的对比,结果表明,DTU10和FES2014模型分别在开阔海域和近海海域精度最优。根据潮汐模型在不同分潮处的精度,如EOT11a模型在O1和K1分潮处精度较高,DTU10在N2,M2,S2和K2分潮处精度较高等,分别构建了开阔海域与近海海域的组合深度基准面模型,计算得知误差分别为11.33和20.95 cm,其精度显著提高。 相似文献
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为在空中三角测量模型较差检测中形象快速标注误差超限点、超限区域,直观揭示误差全局区域联系,给空中三角测量补加连接点提供指引,提高空中三角测量作业效率和精度,结合逐点插入法和数据分块思想改进Delaunay三角网构网算法,提出了一种空中三角测量模型较差平面显示方法,利用Delaunay三角网的优良网拓扑关系显示超限点并推荐误差超限范围。以84景规模实际无控空中三角测量工程对该方法进行验证,结果表明该方法能够快速显示空中三角测量模型较差超限点和区域,指示补点区域,有助于揭示空中三角测量模型较差分布规律,辅助空中三角测量修正。该方法可为空中三角测量模型较差检测实际工程新问题提供高效实践方案。 相似文献
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文中首先介绍了DOT2008A模型建立的原理和方法,利用我国48个长期验潮站19 a连续观测数据验证DOT2008A模型的精度,其均方差为0.118 m,残差的标准偏差为0.086 m;联合多源测高卫星建立的海面地形模型数据验证DOT2008A的精度,均方差为0.106 m,残差的标准偏差为0.099 5 m,且其残差分布图基本符合正态分布。从实验结果来看,DOT2008A模型在我国周边海域精度较高,其建立方法较为合理,转化应用价值较高;同时与多源测高卫星建立的海面地形比较结果来看,验证了自主建立的海面地形模型的正确性,对建立我国高精度海面地形模型具有重要的借鉴意义。 相似文献
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Arctic absolute sea level variations were analyzed based on multi-mission satellite altimetry data and tide gauge observations for the period of 1993–2018. The range of linear absolute sea level trends were found ?2.00 mm/a to 6.88 mm/a excluding the central Arctic, positive trend rates were predominantly located in shallow water and coastal areas, and negative rates were located in high-latitude areas and Baffin Bay. Satellite-derived results show that the average secular absolute sea level trend was (2.53±0.42) mm/a in the Arctic region. Large differences were presented between satellite-derived and tide gauge results, which are mainly due to low satellite data coverage, uncertainties in tidal height processing and vertical land movement (VLM). The VLM rates at 11 global navigation satellite system stations around the Arctic Ocean were analyzed, among which 6 stations were tide gauge co-located, the results indicate that the absolute sea level trends after VLM corrected were of the same magnitude as satellite altimetry results. Accurately calculating VLM is the primary uncertainty in interpreting tide gauge measurements such that differences between tide gauge and satellite altimetry data are attributable generally to VLM. 相似文献
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The data of satellite altimetry are used to simulate the Black-Sea circulation. The altimetry data of the TOPEX/Poseidon and ERS satellites are prepared within the framework of the NASA Ocean Altimeter Pathfinder project. The additional data processing is performed to compute the dynamic level reflecting the circulation of the Black Sea. The altimetry sea-level is assimilated in an eddy-resolving model of circulation of the Black Sea based on primitive equations. The accuracy of the obtained fields of temperature and salinity is estimated by comparing with the data of large-scale hydrographic surveys according to the ComSBlack program. The prognostic capabilities of the proposed model are estimated by comparing the obtained results with the fields computed with the help of assimilation of the altimetry data. 相似文献
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为弥补测高数据在近海区域因为编辑准则被剔除而导致近海测量数据质量不高的缺点,利用5参数模型的两种形式和Ice-2模型对Jason-2卫星在中国南海部分海域的海洋回波波形进行了波形重跟踪的研究,并选择20个海洋回波波形,依据最小二乘原理进行计算、分析、对比,发现5参数模型的指数形式的结果和Ice-2模型结果非常接近。研究结果表明,在开阔的海域,对Jason-2波形进行3种方法波形重跟踪时,可以优先考虑Ice-2模型。波形重跟踪技术能够提高卫星测高数据利用率,为科学研究提供可靠的数据保障。 相似文献
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A New Methodology for Incorporating Tide Gauge Data in Sea Surface Topography Models 总被引：1，自引：0，他引：1
As part of the Vertical Offshore Reference Frames (VORF) project sponsored by the U. K. Hydrographic Office, a new model for Sea Surface Topography (SST) around the British Isles has been developed. For offshore areas (greater than 30 km from the coast), this model is largely derived from satellite altimetry. However, its accuracy and level of detail have been enhanced in coastal areas by the inclusion of not only the 60 PSMSL tide gauges with long-term records around the coasts of the United Kingdom and Ireland but also some 385 gauges established at different epochs and for different observation spans by the U. K. Admiralty. All tide gauge data were brought into a common reference frame by a combination of datum models and direct GPS observations, but a more significant challenge was to bring all short-term sea level observations to an unbiased value at a common epoch. This was achieved through developing a spatial-temporal correlation model for the variations in mean sea level around the British Isles, which in turn meant that gauges with long-term observation spans could be used as control points to improve the accuracy of Admiralty gauges. It is demonstrated that the latter can contribute point observations of mean sea level (MSL) with a precision of 0.078 m. A combination of least squares collocation and interpolation was developed to merge the coastal point and offshore gridded data sets, with particular algorithms having to be developed for different configurations of coastal topology. The resulting model of sea surface topography is shown to present a smooth transition from inshore coastal areas to offshore zones. Further benefits of the techniques developed include an enhanced methodology for detecting datum discontinuities at permanent tide gauges. 相似文献