共查询到20条相似文献，搜索用时 578 毫秒
1.
From the analyses of the satellite altimeter Maps of Sea Level Anomaly(MSLA) data, tidal gauge sea level data and historical sea level data, this paper investigates the long-term sea level variability in the East China Sea(ECS).Based on the correlation analysis, we calculate the correlation coefficient between tidal gauge and the closest MSLA grid point, then generate the map of correlation coefficient of the entire ECS. The results show that the satellite altimeter MSLA data is effective to observe coastal sea level variability. An important finding is that from map of correlation coefficient we can identify the Kuroshio. The existence of Kuroshio decreases the correlation between coastal and the Pacific sea level. Kurishio likes a barrier or a wall, which blocks the effect of the Pacific and the global change. Moreover, coastal sea level in the ECS is mainly associated with local systems rather than global change. In order to calculate the long-term sea level variability trend, the empirical mode decomposition(EMD) method is applied to derive the trend on each MSLA grid point in the entire ECS. According to the 2-D distribution of the trend and rising rate, the sea level on the right side of the axis of Kuroshio rise faster than in its left side. This result supports the barrier effect of Kuroshio in the ECS. For the entire ECS, the average sea level rose 45.0 mm between 1993 and 2010, with a rising rate of(2.5±0.4) mm/a which is slower than global average.The relatively slower sea level rising rate further proves that sea level rise in the ECS has less response to global change due to its own local system effect. 相似文献
2.
Experiments in reconstructing twentieth-century sea levels 总被引：3，自引：0，他引：3
One approach to reconstructing historical sea level from the relatively sparse tide-gauge network is to employ Empirical Orthogonal Functions (EOFs) as interpolatory spatial basis functions. The EOFs are determined from independent global data, generally sea-surface heights from either satellite altimetry or a numerical ocean model. The problem is revisited here for sea level since 1900. A new approach to handling the tide-gauge datum problem by direct solution offers possible advantages over the method of integrating sea-level differences, with the potential of eventually adjusting datums into the global terrestrial reference frame. The resulting time series of global mean sea levels appears fairly insensitive to the adopted set of EOFs. In contrast, charts of regional sea level anomalies and trends are very sensitive to the adopted set of EOFs, especially for the sparser network of gauges in the early 20th century. The reconstructions appear especially suspect before 1950 in the tropical Pacific. While this limits some applications of the sea-level reconstructions, the sensitivity does appear adequately captured by formal uncertainties. All our solutions show regional trends over the past five decades to be fairly uniform throughout the global ocean, in contrast to trends observed over the shorter altimeter era. Consistent with several previous estimates, the global sea-level rise since 1900 is 1.70 ± 0.26 mm yr−1. The global trend since 1995 exceeds 3 mm yr−1 which is consistent with altimeter measurements, but this large trend was possibly also reached between 1935 and 1950. 相似文献
3.
首先用卫星测高资料计算了1993～2009年6月的全球平均海平面变化。用GRACE(gravity recovery andclimate experiment)时变重力场系数反演了2003～2009年6月全球平均海水质量变化。联合GRACE和卫星测高资料计算了2003～2009年6月的热容海平面变化,该变化呈上升趋势。用日本气象局Ishii等提供的海温数据计算了1993～2006年的海水引起的平均热膨胀海平面变化,1993～2003年间,全球海洋热膨胀引起的热容海平面呈上升趋势,约占同期平均海平面变化的一半。利用ARGO温盐数据计算了2004～2009年6月平均热容海平面变化,也呈上升态势,只是变化速率有所减慢。 相似文献
4.
5.
Abstract We estimate secular changes in steric sea level in the northeast Pacific Ocean using the 27‐year time series of monthly hydrographic observations for Station PAPA (50°N, 145°W). Linear trends based on the entire data record suggest that steric heights relative to 1000 db are increasing at a rate of 0.93 mm/yr and that 67% of this increase is due to thermosteric changes at depths below 100 m; the smaller halosteric contribution to the steric trend appears to be confined to the upper 100 m. A trend of 0(1 mm/yr) is consistent with estimates of sea level rise based on coastal tide gauge records. However, a critical examination of the results indicates that sea level changes of such small magnitude would be masked by the large (1–10 cm) interannual variability of open ocean steric height. This is verified by recalculation of trends using abridged versions of the data set. We conclude that our trend estimates are still open to question and that the present 27‐year time series is too short to permit accurate resolution of possible climate‐induced changes in global sea level. 相似文献
6.
气候变化背景下,海平面上升叠加台风—风暴潮、天文大潮等产生的海岸极值水位事件趋多增强,对我国滨海城市社会经济可持发展构成了严重威胁。为认识未来我国滨海城市海岸极值水位危害性（强度和频率）的变化,本文首先采用第五次国际耦合模式比较计划（CMIP5）数据,分析了不同气候情景下（RCP2.6, 4.5, 8.5,简称为RCPs）下,未来不同年代（2030年、2050年和2100年）我国滨海城市沿岸海平面变化幅度;其次,基于沿海验潮站的历史观测资料和文献数据,分析了未来热带气旋强度变化对海岸极值水位的影响;最后,利用皮尔逊Ⅲ型（P-Ⅲ）水文概率曲线方法,预估了不同气候（RCPs）情景下未来不同年代（2030年、2050年和2100年）我国9个滨海城市海岸极值水位重现期的变化。结果表明：（1）在不同气候情景下,我国滨海城市沿海平均海平面均呈现上升趋势,其中,到21世纪末,长三角地区沿海海平面上升幅度最大,上升速度比全国平均高出约30%;（2）热带气旋的强度与台风—风暴潮的增水幅度存在正相关关系。预计到21世纪末,热带气旋的整体强度很可能将增强,热带气旋引发的台风—风暴潮的增水幅度较当前很可能有明显提高。（3）未来我国滨海城市沿海极值水位将有显著增高的趋势,当前极值水位的重现期将明显缩短。到21世纪末,我国滨海城市当前百年一遇的极值水位,重现期几乎都将缩短至20年一遇以下,其中,大连、青岛、上海和厦门等城市海岸极值水位重现期很可能缩短为（或低于）1年一遇。本文虽在一定程度上反映了不同气候情景下海岸洪水危害性的变化,但对于未来热带气旋的变化及其影响的研究尚有待进一步深入。 相似文献
7.
Steric sea level changes estimated from historical ocean subsurface temperature and salinity analyses 总被引：13，自引：0，他引：13
Masayoshi Ishii Masahide Kimoto Kenji Sakamoto Sin-Iti Iwasaki 《Journal of Oceanography》2006,62(2):155-170
An historical objective analysis of subsurface temperature and salinity was carried out on a monthly basis from 1945 to 2003
using the latest observational databases and a sea surface temperature analysis. In addition, steric sea level changes were
mainly examined using outputs of the objective analyses. The objective analysis is a revised version of Ishii et al. and is
available at 16 levels in the upper 700 m depth. Artificial errors in the previous analysis during the 1990s have been worked
out in the present analysis. The steric sea level computed from the temperature analysis has been verified with tide gauge
observations and TOPEX/Poseidon sea surface height data. A correction for crustal movement is applied for tide gauge data
along the Japanese coast. The new analysis is suitable for the discussion of global warming. Validation against the tide gauge
reveals that the amplitude of thermosteric sea level becomes larger and the agreement improves in comparison with the previous
analysis. A substantial part of local sea level rise along the Japanese coast appears to be explained by the thermosteric
effect. The thermal expansion averaged in all longitudes from 60°S to 60°N explains at most half of recent sea level rise
detected by satellite observation during the last decade. Considerable uncertainties remain in steric sea level, particularly
over the southern oceans. Temperature changes within MLD make no effective contribution to steric sea level changes along
the Antarctic Circumpolar Current. According to statistics using only reliable profiles of the temperature and salinity analyses,
salinity variations are intrinsically important to steric sea level changes in high latitudes and in the Atlantic Ocean. Although
data sparseness is severe even in the latest decade, linear trends of global mean thermosteric and halosteric sea level for
1955 to 2003 are estimated to be 0.31 ± 0.07 mm/yr and 0.04 ± 0.01 mm/yr, respectively. These estimates are comparable to
those of the former studies. 相似文献
8.
中国沿岸现代海平面变化及未来趋势分析 总被引：2，自引：0，他引：2
本文用线性回归分析方法，分１９８５年以前和１９９２年以前两个时段，对我国沿岸２５个验潮站近百年来的海平面资料进行了系统分析，计算了两个时段相对海平面变化的年速率和平均海面高度，论述了海平面变化的主要控制因素，并对未来海平面变化趋势进行了预测。计算结果表明，近百年来我国沿岸相对海平面在总体上不但持续上升，而且近年来上升速率普遍加快；根据海平面变化的主要控制因素变化趋向，预计到下世纪中叶前后，全球性海平面大幅度上升的可能性不大，我国沿岸区域性海乎面平均上升幅度不超过１５ｃｍ，不同岸段因地壳升降差异性大而有较大差别。 相似文献
9.
Sea level variations in the regional seas around Taiwan 总被引：2，自引：0，他引：2
The patterns and trends of sea level rise in the regional seas around Taiwan have been investigated through the analyses of
long-term tide-gauge and satellite altimetry data. Series of tide-gauge data extending over 50 years reveal decadal and interannual
variations and spatially-inhomogeneous patterns of generally rising sea level. The East Asia tide-gauge stations around Taiwan
show an average trend of +2.4 mm/yr from 1961–2003, which is larger than the reported global rate of +1.8 mm/yr for the same
period. These stations also show significantly larger sea level rise rates (+5.7 mm/yr) than global values (+3.1 mm/yr) during
the period from 1993–2003. Consistent with the coastal tide-gauge records, satellite altimetry data show similar increasing
rates (+5.3 mm/yr) around Taiwan during the same period. Comparisons with temperature anomalies in the upper ocean suggest
that thermal expansion and heat advection in the upper layer contribute significantly to the long-term sea level variations
in this area with correlations >0.9 for observations after 1992. Thermosteric sea level variations may also explain the interannual
and decadal variations of the observed sea level rises around Taiwan. Our analysis also indicates that the altimetry data
are only part of a long-term, larger-scale signal. Finally, we have found that a non-linear smoother, LOESS, is more suitable
for extracting long-term trends in sea level than the traditional linear regression approach. 相似文献
10.
带周期项的海平面变化灰色分析模型及广西海平面变化分析 总被引：7，自引：0，他引：7
提出了一种带周期项的海平面变化灰色分析模型.该模型保持了GM(1,1)模型能较好反应海平面变化趋势的优点,不仅能求出海平面变化速率,还能方便求出海平面变化的加速度,同时,该模型能较好的模拟海平面变化中的周期现象,从而克服了GM(1,1)不能预报周期性显著的月平均海面的缺点,并提高了预报精度.模型用于广西沿岸海平面变化分析,结果表明北海、涸洲、白龙尾3站的相对海平面上升速率分别为1.67、2.51、0.89mm/a;石头埠相对海平面呈下降趋势,下降速率为0.5～1.0mm/a;广西沿岸绝对海平面上升速率为2.0mm/a.和线性趋势项与周期项叠加的海平面分析模型相比,两者模拟精度相当. 相似文献
11.
沿海水位和大尺度气候状态——降尺度技术在日本列岛的应用 相似文献
12.
ＡｎｏｍａｌｏｕｓｃｈａｎｇｅｏｆｔｈｅＡｎｔａｒｃｔｉｃｓｅａｉｃｅａｎｄｇｌｏｂａｌｓｅａｌｅｖｅｌｃｈａｎｇｅ￥ＸｉｅＳｉｍｅｉ;ＺｏｕＢｉｎｇ;ＷａｎｇＹｉａｎｄＢａｏＣｈｅｎｇｌａｎ（１．ＮａｔｉｏｎａｌＭａｒｉｎｅＥｎｖｉｒｏｎｍｅｎｔＦ... 相似文献
13.
相对海平面上升对中国沿海地区的可能影响 总被引：6，自引：0，他引：6
本文论述了相对海平面变化研究的重要性,并在IPCC提供的全球海平面变化背景值之上,给出中国未来几十年相对海平面变化的预测值。中国大河三角洲地区未来几十年相对海平面皆呈上升趋势,但幅度不同。因此,充分认识相对海平面上升将导致的危害就显得极为重要和迫切。相对海平面上升将对中国沿海地区产生以下影响：(1)导致海岸侵蚀,扩大侵蚀范围;(2)风暴潮强度与频率增加：(3)沿海低地与湿地被淹没;(4)海水入侵加剧,范围扩大,水资源和水环境遭到破坏;(5)防汛工程功能降低,洪涝灾害加剧。因此,沿海地区政府决策应考虑未来相对海平面变化的影响。 相似文献
14.
Tariq Masood Ali Khan D. A. Razzaq Qamar-Uz-Zaman Chaudhry Dewan Abdul Quadir Anwarul Kabir Majajul Alam Sarker 《Marine Geodesy》2013,36(1-2):159-174
The UNEP in its regional seas program in 1989 has included Pakistan in a group of countries which are vulnerable to the impact of rising sea level. If the present trend of sea level rise (SLR) at Karachi continues, in the next 50 years the sea level rise along the Pakistan Coast will be 50 mm (5 cm). Since the rising rates of sea level at Karachi are within the global range of 1-2 mm/year, the trends may be treated as eustatic SLR. Historical air temperature and sea surface temperature (SST) data of Karachi also show an increasing pattern and an increasing trend of about 0.67°C has been registered in the air temperature over the last 35 years, whereas the mean SST in the coastal waters of Karachi has also registered an increasing trend of about 0.3°C in a decade. Sindh coastal zone is more vulnerable to sea level rise than Baluchistan coast, as uplifting of the coast by about 1-2 mm/year due to subduction of Indian Ocean plate is a characteristic of Baluchistan coast. Within the Indus deltaic creek system, the area nearby Karachi is more vulnerable to coastal erosion and accretion than the other deltaic region, mainly due to human activities together with natural phenomena such as wave action, strong tidal currents, and rise in sea level. Therefore, The present article deals mainly with the study of dynamical processes such as erosion and accretion associated with sea level variations along the Karachi coast and surrounding Indus deltaic coastline. The probable beach erosion in a decade along the sandy beaches of Karachi has been estimated. The estimates show that 1.1 mm/year rise in sea level causes a horizontal beach loss of 110 mm per year. Therefore, coast eroded with rise in sea level at Karachi and surrounding sandy beaches would be 1.1 m during a period of next 10 years. The northwestern part of Indus delta, especially the Gizri and Phitti creeks and surrounding islands, are most unstable. Historical satellite images are used to analyze the complex pattern of sediment movements, the change in shape of coastline, and associated erosion and accretion patterns in Bundal and Buddo Islands. The significant changes in land erosion and accretion areas at Bundal and Buddo Islands are evident and appear prominently in the images. A very high rate of accretion of sediments in the northwestern part of Buddo Island has been noticed. In the southwest monsoon season the wave breaking direction in both these islands is such that the movement of littoral drift is towards west. Erosion is also taking place in the northeastern and southern part of Bundal Island. The erosion in the south is probably due to strong wave activities and in the northeast is due to strong tidal currents and seawater intrusion. Accretion takes place at the northwest and western parts of Bundal Island. By using the slope of Indus delta, sea encroachment and the land area inundation with rising sea level of 1 m and 2 m have also been estimated. 相似文献
15.
夏江江 严中伟 周文 FONG Soi Kun LEONG Ka Cheng TANG Iu Man CHANG S W LEONG W K 靳少非 《海洋学报(英文版)》2015,34(9):78-84
Projections of potential submerged area due to sea level rise are helpful for improving understanding of the influence of ongoing global warming on coastal areas. The Ensemble Empirical Mode Decomposition method is used to adaptively decompose the sea level time series in order to extract the secular trend component. Then the linear relationship between the global mean sea level(GMSL) change and the Zhujiang(Pearl) River Delta(PRD)sea level change is calculated: an increase of 1.0 m in the GMSL corresponds to a 1.3 m(uncertainty interval from1.25 to 1.46 m) increase in the PRD. Based on this relationship and the GMSL rise projected by the Coupled Model Intercomparison Project Phase 5 under three greenhouse gas emission scenarios(representative concentration pathways, or RCPs, from low to high emission scenarios RCP2.6, RCP4.5, and RCP8.5), the PRD sea level is calculated and projected for the period 2006–2100. By around the year 2050, the PRD sea level will rise 0.29(0.21 to 0.40) m under RCP2.6, 0.31(0.22 to 0.42) m under RCP4.5, and 0.34(0.25 to 0.46) m under RCP8.5, respectively.By 2100, it will rise 0.59(0.36 to 0.88) m, 0.71(0.47 to 1.02) m, and 1.0(0.68 to 1.41) m, respectively. In addition,considering the extreme value of relative sea level due to land subsidence(i.e., 0.20 m) and that obtained from intermonthly variability(i.e., 0.33 m), the PRD sea level will rise 1.94 m by the year 2100 under the RCP8.5scenario with the upper uncertainty level(i.e., 1.41 m). Accordingly, the potential submerged area is 8.57×103 km2 for the PRD, about 1.3 times its present area. 相似文献
16.
Tariq Masood Ali Khan D. A. Razzaq Qamar-Uz-Zaman Chaudhry Dewan Abdul Quadir Anwarul Kabir Majajul Alam Sarker 《Marine Geodesy》2002,25(1):159-174
The UNEP in its regional seas program in 1989 has included Pakistan in a group of countries which are vulnerable to the impact of rising sea level. If the present trend of sea level rise (SLR) at Karachi continues, in the next 50 years the sea level rise along the Pakistan Coast will be 50 mm (5 cm). Since the rising rates of sea level at Karachi are within the global range of 1-2 mm/year, the trends may be treated as eustatic SLR. Historical air temperature and sea surface temperature (SST) data of Karachi also show an increasing pattern and an increasing trend of about 0.67°C has been registered in the air temperature over the last 35 years, whereas the mean SST in the coastal waters of Karachi has also registered an increasing trend of about 0.3°C in a decade. Sindh coastal zone is more vulnerable to sea level rise than Baluchistan coast, as uplifting of the coast by about 1-2 mm/year due to subduction of Indian Ocean plate is a characteristic of Baluchistan coast. Within the Indus deltaic creek system, the area nearby Karachi is more vulnerable to coastal erosion and accretion than the other deltaic region, mainly due to human activities together with natural phenomena such as wave action, strong tidal currents, and rise in sea level. Therefore, The present article deals mainly with the study of dynamical processes such as erosion and accretion associated with sea level variations along the Karachi coast and surrounding Indus deltaic coastline. The probable beach erosion in a decade along the sandy beaches of Karachi has been estimated. The estimates show that 1.1 mm/year rise in sea level causes a horizontal beach loss of 110 mm per year. Therefore, coast eroded with rise in sea level at Karachi and surrounding sandy beaches would be 1.1 m during a period of next 10 years. The northwestern part of Indus delta, especially the Gizri and Phitti creeks and surrounding islands, are most unstable. Historical satellite images are used to analyze the complex pattern of sediment movements, the change in shape of coastline, and associated erosion and accretion patterns in Bundal and Buddo Islands. The significant changes in land erosion and accretion areas at Bundal and Buddo Islands are evident and appear prominently in the images. A very high rate of accretion of sediments in the northwestern part of Buddo Island has been noticed. In the southwest monsoon season the wave breaking direction in both these islands is such that the movement of littoral drift is towards west. Erosion is also taking place in the northeastern and southern part of Bundal Island. The erosion in the south is probably due to strong wave activities and in the northeast is due to strong tidal currents and seawater intrusion. Accretion takes place at the northwest and western parts of Bundal Island. By using the slope of Indus delta, sea encroachment and the land area inundation with rising sea level of 1 m and 2 m have also been estimated. 相似文献
17.
To better monitor the vertical crustal movements and sea level changes around Greenland, multiple data sources were used in this paper, including global positioning system(GPS), tide gauge, satellite gravimetry, satellite altimetry, glacial isostatic adjustment(GIA). First, the observations of more than 50 GPS stations from the international GNSS service(IGS) and Greenland network(GNET) in 2007–2018 were processed and the common mode error(CME) was eliminated with using the principal component analysis(PCA). The results show that all GPS stations show an uplift trend and the stations in southern Greenland have a higher vertical speed. Second, by deducting the influence of GIA, the impact of current Gr IS mass changes on GPS stations was analysed, and the GIA-corrected vertical velocity of the GPS is in good agreement with the vertical velocity obtained by gravity recovery and climate experiment(GRACE). Third, the absolute sea level change around Greenland at 4 gauge stations was obtained by combining relative sea level derived from tide gauge observations and crustal uplift rates derived from GPS observations, and was validated by sea level products of satellite altimetry. The results show that although the mass loss of Gr IS can cause considerable global sea level rise, eustatic movements along the coasts of Greenland are quite complex under different mechanisms of sea level changes. 相似文献
18.
区域海平面变化是目前气候变化研究的热点问题。海平面变化具有时间和空间的异质性,分析海平面变化,应充分考虑时间和空间的差异。基于集合经验模态分解(Ensemble Empirical Mode Decomposition,EEMD)、最小二乘法,利用卫星高度计、验潮站数据,分析了1993—2016年间中国近海及周边海域海平面的时空变化规律。利用EEMD,计算了1993—2016年中国近海海平面变化空间结构的时间变化规律。结果表明中国近海海平面持续升高,但海平面变化在空间分布和时间上的变化并不均匀。空间结构大致分三个部分:大陆沿岸海平面持续上升且上升速率逐年增加,近海海区升高速率逐年降低,而研究区域内的西太平洋西部海区先减速升高又加速降低。分别利用EEMD分解和线性最小二乘拟合算法计算了1993—2016年中国近海海平面平均上升速率的空间分布,结果表明两种方法得到的海平面升高速率的空间分布大致吻合。两种方法均显示沿海地区的上升速率远大于近海海区,沿海地区上升速率大约为6 mm/a,近海海区上升速率大约为2 mm/a。但EEMD方法显示在广东沿岸和靠近赤道部分区域的上升速率更大。分别计算了大陆沿岸、近海及西太平洋西部海区三个海区内空间平均的海平面时间变化的线性及非线性趋势。非线性趋势显示大陆沿岸海区海平面加速上升,上升速率由1993年的3.65 mm/a,增加到2016年的5.03 mm/a;近海地区海平面上升速率逐年变小,由1993年的4.51 mm/a,减缓至2016年的3.8 mm/a;西太平洋西部海区海平面先减速上升,后加速下降,从1993年的上升率为9.5 mm/a,逐渐变化到2016年的下降率为2.27 mm/a。利用验潮站数据分析了大连、坎门、香港的水位变化,除大连海平面上升速率降低外,其余均显示海平面上升速度逐年升高,和卫星高度计的结果吻合。 相似文献
19.
卫星重力估计陆地水和冰川对全球海平面变化的贡献 总被引：2，自引：0，他引：2
重力场恢复与气候试验（GRACE）卫星为高分辨率地监测全球海洋质量变化提供了一种新的手段。利用2003年1月至2014年12月Level-2 RL05的GRACE产品，进行去相关误差滤波、高斯滤波和海洋-陆地信号泄漏改正后，得到了全球陆地和海水质量变化，并分析了陆地水和冰川的质量变化对海平面长期变化的贡献。研究表明，全球陆地水和冰川的质量变化对海平面的贡献约为（2.09±0.54）mm/a，与卫星测高扣除海洋温盐数据比热容变化得到的海水质量长期变化（2.07±0.62）mm/a有着很好的一致性，其中全球陆地水储量对全球质量项海平面变化的贡献为（0.15±0.25）mm/a，南极冰盖对全球质量项海平面变化的贡献为（0.59±0.10）mm/a，格陵兰岛冰盖对全球质量项海平面变化的贡献为（0.72±0.12）mm/a，山地冰川对全球质量项海平面变化的贡献为（0.63±0.09）mm/a。并进一步讨论了不同分析中心GRACE重力场系数，一阶项系数和二阶项对质量项海平面变化的影响。结果表明，一阶项对质量项海平面的影响为（0.10±0.08）mm/a，二阶项对质量项海平面的影响为（0.16±0.04）mm/a，美国德克萨斯大学空间研究中心和德国地学研究中心分析结果较为一致，而美国国家航空航天局喷气推进实验室的结果则稍稍偏小。 相似文献
20.
通过对福建沿岸多年来已有的当地平均海面高程资料和与1985国家高程基准的水准点联测成果，分析并研究了福建沿岸主要验潮站的当地平均海面的高程情况和变化趋势，对福建沿岸当地平均海面的高程（1985国家高程基准）进行了比较深入的研究和探讨，阐述了福建沿岸与浙江、广东沿海平均海面高程的连续性和与我国海区平均海面高程的一致性，论述了当地平均海面高程的应用方法，以解决福建沿海海岸地形图和水深图的基准统一及高度衔接问题。 相似文献