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491.
Rongxing Li 《Marine Geodesy》2013,36(1):57-59
J. Albertz. Grundlagen der Interpretation von Luft‐und Satellitenbildern: eine Einfuhrung in die Fernerkundung (Fundamentals of Interpretation of Aerial and Satellite Images: An Introduction to Remote Sensing). Darmstadt: Wissenschaftliche Buchgesellschaft, 1991. 204 pp. Hardcover. U.S. $40.00–45.00. ISBN 3–534–07838–1. International Symposium on Marine Positioning Proceedings, “Marine Positioning into the 1990's.” Marine Geodesy Committee/MTS, 1991. 594 pp. Hardcover. U.S. $139.00. ISBN 91–060360. 相似文献
492.
利用全球导航卫星系统的反射信号GNSS-R(global navigation satellite system-reflection)对海洋进行观测,目前已经成为一种新型遥感手段。介绍了一种最新研制的GNSS-R系统,以及使用该系统在北京怀柔水库开展的GNSS-R岸基测高实验。实验的目的,是在理想的湖面条件下验证系统的性能和检验测高算法的精度。实验得出:该系统能够在天线各阵元组合情况下实现GPS-R(global position system-reflection)信号的接收和处理;在把反演结果平均到1h后,使用C/A码的测高精度可达分米数量级。 相似文献
493.
494.
Ocean Tide Models Developed by Assimilating TOPEX/POSEIDON Altimeter Data into Hydrodynamical Model: A Global Model and a Regional Model around Japan 总被引:36,自引:0,他引:36
A global ocean tide model (NAO.99b model) representing major 16 constituents with a spatial resolution of 0.5° has been estimated by assimilating about 5 years of TOPEX/POSEIDON altimeter data into barotropic hydrodynamical model. The new solution is characterized by reduced errors in shallow waters compared to the other two models recently developed; CSR4.0 model (improved version of Eanes and Bettadpur, 1994) and GOT99.2b model (Ray, 1999), which are demonstrated in comparison with tide gauge data and collinear residual reduction test. This property mainly benefits from fine-scale along-track tidal analysis of TOPEX/POSEIDON data. A high-resolution (1/12°) regional ocean tide model around Japan (NAO.99Jb model) by assimilating both TOPEX/POSEIDON data and 219 coastal tide gauge data is also developed. A comparison with 80 independent coastal tide gauge data shows the better performance of NAO.99Jb model in the coastal region compared with the other global models. Tidal dissipation around Japan has been investigated for M2 and K1 constituents by using NAO.99Jb model. The result suggests that the tidal energy is mainly dissipated by bottom friction in localized area in shallow seas; the M2 ocean tidal energy is mainly dissipated in the Yellow Sea and the East China Sea at the mean rate of 155 GW, while the K1 energy is mainly dissipated in the Sea of Okhotsk at the mean rate of 89 GW. TOPEX/POSEIDON data, however, detects broadly distributed surface manifestation of M2 internal tide, which observationally suggests that the tidal energy is also dissipated by the energy conversion into baroclinic tide. 相似文献
495.
496.
A detailed accuracy assessment of the geopotential model Jgm3 is made based on independent single- and dual-satellite sea-height
differences at crossovers from altimetry with Jgm3-based orbits. These differences, averaged over long time spans and in latitude
bands, are converted to spectra (latitude-lumped coefficients) by least-squares estimation. The observed error spectra so
obtained are then compared directly to error projections for them from the Jgm3 variance–covariance matrix. It is found from
these comparisons that Jgm3 is generally well calibrated with respect to the crossover altimetry of and between Geosat, TOPEX/Poseidon
(T/P), and Ers 1. Some significant discrepancies at a few lower orders (namely m=1 and 3) indicate a need for further improvement of Jgm3. A companion calibration (by order) of the geopotential model Jgm2
shows its variance–covariance matrix also to be generally well calibrated for the same single- and dual-satellite altimeter
data sets (but based on Jgm2 orbits), except that the error projections for Geosat are too pessimistic. The analysis of the
dual-satellite crossovers reveals possible relative coordinate system offsets (particularly for Geosat with respect to T/P)
which have been discussed previously. The long-term detailed seasonally averaged Geosat sea level with respect to T/P (covering
1985–1996) should be useful in gauging the relative change in sea level between different parts of the ocean over the single
4-year gap between these missions (1988–1992).
Received: 16 February 1998 / Accepted: 25 November 1998 相似文献
497.
GRACE卫星的成功发射为海底沉积物的监测提供了新的方法.利用2003-2014年间的GRACERL05数据,采用同期的测高数据对海面高变化进行改正,使用水文模式数据和基于均一假设的尺度因子估计方法处理泄漏误差,反演了东海地区的沉积物变化情况,并对GIA效应进行了改正.结果表明:东海入海口处沉积物的平均变化速率为5.44±0.88mm·a^-1,最大值出现在浙江沿海地区,变化速率为6~7mm·a^-1;在空间分布上,呈现河口处沉积速率大,远离河口的大洋地区沉积速率小的特征.在时空分布上均与实测数据很好的吻合.沉积物变化时间序列的周年项振为6.8cm,周年变化主要与东海泥沙扩散路径相关的海洋环流模式有关;半周年项和两周年项振幅分别为0.6cm和0.7cm,这两项变化主要与长江流域降水引起的土壤侵蚀变化有关.最后,分析讨论了本文沉积物监测方法推广到其他地区的适用性和局限性. 相似文献
498.
利用TOPEX/Poseidon卫星测高资料监测全球海平面变化 总被引:17,自引:1,他引:17
本文利用1993年1月至1999年5月的TOPEX/Poseidon卫星测高数据计算了全球海平变化。海平面模型误差和不恰当的加权方法都会影响全球海平面序列的周年变化,潮汐模型误差对于季节性变化有明显的影响。利用两个高度计算的海平面变化存在周年变化存在明显的差异,利用TOPEX高度计和Poseidon高度计得到的该时段全球平均海平面的变化率分别为2.0mm/a和-0.5mm/a。与南方涛动指数的比较 相似文献
499.