Vertical Land Motion by satellite Altimetry and tide gauge Difference

卫星测高和潮汐计差异的垂直陆地运动

• 批准号: 411072120
• 负责人: Dr. Marcello Passaro
• 金额: --
• 依托单位: Deutsches Geodätisches Forschungsinstitut
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2018
• 资助国家: 德国
• 起止时间: 2017-12-31 至 2022-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/411072120?language=en
• 关键词: Vertical; Land; Motion; satellite; Altimetry

The impact that sea level rise will have at particular locations depends also on the local movements of the Earth crust, as vertical land motion (VLM) is in many places of the same order of magnitude (1-10 mm/yr) as the sea level rise itself and displays significant spatial variations. Given the potentially hazardous effects of sea level rise, measuring and interpreting the sea level trends relative to the land are vital challenges for climate change understanding and adaptation.To separate the contributions from crustal motions and absolute sea level rise from the in-situ (tide gauges, TGs) observations, geodetic VLM estimates can be used if a coastal geodetic stations and a TG are co-located, which is true for only 5% of the network. To extend the estimations to the other TGs, satellite altimetry, which provides absolute sea level measurements and has a global coverage, can be used in combination by differentiating the sea level time series, assuming that the residuals are due to the land motion (TG-Alt method). The accuracy of this promising application has been hampered by the quality of satellite altimetry data in the coastal zone.This project aims at providing a VLM map based on TG-Alt using for the first time a coastal-dedicated reprocessing of the altimetry data, including a specialised algorithm to fit the radar signal and an evaluation of the available corrections. A "zone of influence" of the sea level variability for each tide gauge will be defined in order to take into account the short wavelength variations typical of shelf seas and coastal waters, while maximizing the number of altimetry measurements. The uncertainties will be provided by the statistical analysis of TG-Alt residuals.A further aim is to improve the density of the geodetic network by harmonising the solutions of multiple datasets in order to make compatible the vertical motion rates referred to different Terrestrial Reference Frame (TRF) versions. These estimates will then be used as control points to evaluate the TG-Alt VLM map. Finally, the overall purpose is the estimation of relative coastal sea level trends during the "satellite era" (starting from 1993) by combining the altimetry data with the TG-Alt VLM points in a coastal map to be defined in specific regions. The resulting map of relative trends will constitute an innovative tool to be used, for example for risk assessment studies.

海平面上升在特定位置的影响也取决于地壳的局部运动，因为垂直土地运动（VLM）在许多位置的数量级（1-10 mm/yr）的许多位置随海平面上升并显示出显着的空间变化。鉴于海平面上升的潜在危险影响，衡量和解释海平面相对于土地的趋势是气候变化理解和适应的重要挑战，要将贡献与地壳运动和绝对海平面分开，并且绝对海平面与位于原地（TGE，TGS，TGS，TGS，TGS）的观察值，Geodetic VLM估计仅在伊斯特（Ise）的估计中使用Isations Geodications geodications geodecations和t.网络。为了将估计扩展到其他TGS，可以通过区分海平面时间序列来组合使用绝对海平面测量并具有全球覆盖范围的卫星高度法，假设残差是由于土地运动造成的（TG-ALT方法）。沿海地区的卫星高度测定数据的质量阻碍了这种有前途的应用的准确性。该项目旨在提供基于TG-ALT的VLM地图，首次使用TG-ALT使用沿海沿海化的高度数据重新处理高度数据，包括专门的ALGORITHM，以适合雷达信号和可用的评估。将定义每个潮汐量规的海平面变异性的“影响区”，以考虑货架海和沿海水域典型的短波长变化，同时最大程度地提高高度法测量的数量。不确定性将通过TG-ALT残差的统计分析提供。进一步的目的是通过协调多个数据集的解决方案来提高地球网络的密度，以使兼容兼容垂直运动速率，称为不同的地面参考框架（TRF）版本。然后，这些估计将用作评估TG-ALT VLM MAP的控制点。最后，总体目的是估计“卫星时代”（从1993年开始）中相对沿海海平面趋势的估计，这是通过将高度学数据与特定地区定义的沿海地图中的TG-ALT VLM点相结合。所得的相对趋势图将构成要使用的创新工具，例如进行风险评估研究。