Energy transfers among internal waves in the northern South China Sea are not well characterized,particularly during typhoons,owing to the lack of in situ observations.Based on high-resolution mooring data collected d...Energy transfers among internal waves in the northern South China Sea are not well characterized,particularly during typhoons,owing to the lack of in situ observations.Based on high-resolution mooring data collected during Typhoon Trami(2024),this study reveals the occurrence of robust vertical energy redistribution among diurnal internal tides(D1 ITs)and near-inertial waves(NIWs).Strikingly,the typhoon not only amplified the NIW energy but also triggered an unexpected surge in the D1 IT energy.The observed average net energy transfer rate of 1×10^(-7) W kg^(−1) from typhoon-forced NIWs to D1 ITs occurred at water depths of 120-170 m.Further bispectral analysis indicated that the energy transfer is driven by nonlinear wave—wave interaction.These results reveal the existence of a new energy transfer pathway—from atmospheric forcing to D1 ITs—and redefine the redistribution of the internal wave energy during extreme weather events.展开更多
This study investigates the rate of sea level rise along the Estonian coastline of the Baltic Sea over the three decades(1993-2022)using tide gauge data and advanced analytical methods.Tide gauge data were analyzed us...This study investigates the rate of sea level rise along the Estonian coastline of the Baltic Sea over the three decades(1993-2022)using tide gauge data and advanced analytical methods.Tide gauge data were analyzed using an open-source software based on the"TG Analysis"method developed by Kristian Breili.The results reveal significant spatial and temporal variability:the average relative sea level rise was 1.35±1.91 mm/yr over the three decades,with a notable acceleration to 9.01±8.67 mm/yr in the last decade(2013-2022).Absolute sea level rise,after correction for land uplift(NKG2016LU),averaged4.16±1.81 mm/yr.Regional differences were observed,with faster relative sea level rise in areas of slower land uplift(e.g.,P??rnu,Virtsu)and vice versa.The data and trends were further analyzed by applying advanced analytical methods(differentiation,spectral and segmented regression analysis,and sea level model validation).By differentiating the sea level rise trends along the Estonian coast,and comparing tide gauge data with data from Stockholm and Hanko,the results show a minimal velocity difference(0.65 mm/yr),confirming the reliability of the trends.Spectral analysis and segmented regression analysis identified breakpoints mainly in the early 1990s,with the transition to automated tide gauges in 2010 having no significant impact.Validation of the ESA BalticSEAL model showed good performance in western Estonia,while larger discrepancies were observed in the northern regions,which are linked to local geophysical factor.展开更多
【研究目的】研究全新世古环境和海面变化对于预测现代地质环境演化趋势具有重要意义。【研究方法】本文以渤海湾西岸沧州北部为研究区,通过取自第V道贝壳堤附近的3个30 m深钻孔样品的硅藻分析和14 C年代学研究,重建了富硅藻层的古环境...【研究目的】研究全新世古环境和海面变化对于预测现代地质环境演化趋势具有重要意义。【研究方法】本文以渤海湾西岸沧州北部为研究区,通过取自第V道贝壳堤附近的3个30 m深钻孔样品的硅藻分析和14 C年代学研究,重建了富硅藻层的古环境和相对海面。【研究结果】3个钻孔虽硅藻整体稀少,但各存在一层由泥炭及腐殖质灰色黏土组成的富硅藻层,厚10~60 cm,由海向陆方向厚度变薄。其中,DC01孔,7473 cal a BP由海水影响的沼泽环境转为陆相淡水沼泽环境,富硅藻层与下伏沼泽层指示当时的相对海面低于-6.37 m;QX02孔,7513 cal a BP由盐沼环境(Ⅰ带)转为受海水影响的沼泽环境(Ⅱ带)再转为受海水影响的盐沼环境(Ⅲ带),Ⅰ带和Ⅱ带界限处指示相对海平面为-6.68 m;QX01孔,7836 cal a BP由淡水沼泽(Ⅰ带)转为盐沼环境(Ⅱ带),Ⅰ带和Ⅱ带界线指示相对海面为-7.68 m。【结论】海面在7.4~7.8 cal ka BP约350年的时间内上升了近1 m,海水影响到第V道贝壳堤以西,盐沼和淡水沼泽环境是全新世海侵达到最大范围时岸线附近的主要环境类型,因此,在现代海面上升背景下,沼泽化是海岸地区面临的一个主要环境问题。展开更多
基金supported by the National Key R&D Plan Program of China [Grant number 2021YFC3101500]the National Natural Science Foundation of China [Grant number 42305014,42506024]。
文摘Energy transfers among internal waves in the northern South China Sea are not well characterized,particularly during typhoons,owing to the lack of in situ observations.Based on high-resolution mooring data collected during Typhoon Trami(2024),this study reveals the occurrence of robust vertical energy redistribution among diurnal internal tides(D1 ITs)and near-inertial waves(NIWs).Strikingly,the typhoon not only amplified the NIW energy but also triggered an unexpected surge in the D1 IT energy.The observed average net energy transfer rate of 1×10^(-7) W kg^(−1) from typhoon-forced NIWs to D1 ITs occurred at water depths of 120-170 m.Further bispectral analysis indicated that the energy transfer is driven by nonlinear wave—wave interaction.These results reveal the existence of a new energy transfer pathway—from atmospheric forcing to D1 ITs—and redefine the redistribution of the internal wave energy during extreme weather events.
基金supported by the Estonian University of Life Sciences Grant P220167MIMP"Sustainable Geodetic Reference Framework for Estonia's Coastal and Mainland Areas to Address Global Climate Challenges"。
文摘This study investigates the rate of sea level rise along the Estonian coastline of the Baltic Sea over the three decades(1993-2022)using tide gauge data and advanced analytical methods.Tide gauge data were analyzed using an open-source software based on the"TG Analysis"method developed by Kristian Breili.The results reveal significant spatial and temporal variability:the average relative sea level rise was 1.35±1.91 mm/yr over the three decades,with a notable acceleration to 9.01±8.67 mm/yr in the last decade(2013-2022).Absolute sea level rise,after correction for land uplift(NKG2016LU),averaged4.16±1.81 mm/yr.Regional differences were observed,with faster relative sea level rise in areas of slower land uplift(e.g.,P??rnu,Virtsu)and vice versa.The data and trends were further analyzed by applying advanced analytical methods(differentiation,spectral and segmented regression analysis,and sea level model validation).By differentiating the sea level rise trends along the Estonian coast,and comparing tide gauge data with data from Stockholm and Hanko,the results show a minimal velocity difference(0.65 mm/yr),confirming the reliability of the trends.Spectral analysis and segmented regression analysis identified breakpoints mainly in the early 1990s,with the transition to automated tide gauges in 2010 having no significant impact.Validation of the ESA BalticSEAL model showed good performance in western Estonia,while larger discrepancies were observed in the northern regions,which are linked to local geophysical factor.
文摘【研究目的】研究全新世古环境和海面变化对于预测现代地质环境演化趋势具有重要意义。【研究方法】本文以渤海湾西岸沧州北部为研究区,通过取自第V道贝壳堤附近的3个30 m深钻孔样品的硅藻分析和14 C年代学研究,重建了富硅藻层的古环境和相对海面。【研究结果】3个钻孔虽硅藻整体稀少,但各存在一层由泥炭及腐殖质灰色黏土组成的富硅藻层,厚10~60 cm,由海向陆方向厚度变薄。其中,DC01孔,7473 cal a BP由海水影响的沼泽环境转为陆相淡水沼泽环境,富硅藻层与下伏沼泽层指示当时的相对海面低于-6.37 m;QX02孔,7513 cal a BP由盐沼环境(Ⅰ带)转为受海水影响的沼泽环境(Ⅱ带)再转为受海水影响的盐沼环境(Ⅲ带),Ⅰ带和Ⅱ带界限处指示相对海平面为-6.68 m;QX01孔,7836 cal a BP由淡水沼泽(Ⅰ带)转为盐沼环境(Ⅱ带),Ⅰ带和Ⅱ带界线指示相对海面为-7.68 m。【结论】海面在7.4~7.8 cal ka BP约350年的时间内上升了近1 m,海水影响到第V道贝壳堤以西,盐沼和淡水沼泽环境是全新世海侵达到最大范围时岸线附近的主要环境类型,因此,在现代海面上升背景下,沼泽化是海岸地区面临的一个主要环境问题。
