Relative sea-level changes from near-, intermediate- and far-field locations and their implications for geophysical modeling and 20th century ice sheet-ocean interactions

近场、中场和远场位置的相对海平面变化及其对地球物理建模和 20 世纪冰盖-海洋相互作用的影响

• 批准号: 1052848
• 负责人: Benjamin Horton
• 金额: $ 11.45万
• 依托单位: University of Pennsylvania
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-04-15 至 2014-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1052848&HistoricalAwards=false
• 关键词: Relative; sea; level; changes; near

The goal of this research is to synthesize a database of sea-level observations in a systematic and rigorous fashion for the Atlantic coast of North America, Bermuda and the Caribbean for the last 20,000 years. The database will facilitate the interpretation of relative sea-level (RSL) change on a regional scale and enable the tuning and refinement of Earth system models that focus on predicting RSL change and its spatial variability. The database consists of 60 study locations, permitting a suite of geophysical parameters to be constrained. Earth?s lower mantle viscosity will be defined by near-field and ice-margin RSL data from the Atlantic coast of Canada and northeastern United States while the upper mantle viscosity will be reliant on intermediate-field RSL data from the mid Atlantic. Far-field RSL data from the southern United States and Caribbean will constrain ice-equivalent meltwater input. The database will be further used to decontaminate 20th century rates of sea-level rise from tides gauges to reveal spatial variability related to ocean mass and volume changes.At the heart of this project is a database of sea level from North America (the Atlantic coast of Canada and the United States) and the Caribbean that stretches back 20,000 years. This will be significant to a number of disciplines in the Earth sciences. For example, careful reconstruction of sea levels from the past will reveal the contribution from land-based ice to sea-level change during deglaciation after the last ice age. In addition, the data will provide vital constraints on key parameters in geophysical models of the Earth that are used in a variety of other applications (e.g., plate tectonics, glaciology and paleoclimate). Overall, the observations will extend the time range of comparisons with historical and present-day changes. Consequently, this research promises to increase our understanding of the driving mechanisms of sea level change and enhance our predictions of 21st century sea-level rise. The research will also provide an important and unique contribution to the assessment of national hazards with respect to sea-level rise and coastal responses.

这项研究的目标是以系统和严格的方式综合一个过去20 000年来北美大西洋沿岸、百慕大和加勒比海平面观测数据库。该数据库将有助于在区域范围内解释相对海平面变化，并能够调整和完善侧重于预测相对海平面变化及其空间变异性的地球系统模型。该数据库包括60个研究地点，允许一套地球物理参数的约束。地球？的下地幔粘度将被定义的近场和冰缘RSL数据从大西洋沿岸的加拿大和美国东北部，而上地幔粘度将依赖于中间场RSL数据从大西洋中部。来自美国南部和加勒比地区的远场RSL数据将限制冰当量的融水输入。该数据库还将进一步用于从验潮仪中排除20世纪世纪海平面上升率的影响，以揭示与海洋质量和体积变化有关的空间变异性，该项目的核心是一个关于北美（加拿大和美国的大西洋沿岸）和加勒比海平面的数据库，可追溯到20 000年前。这将对地球科学的一些学科具有重要意义。例如，仔细重建过去的海平面将揭示最后一个冰河时代后冰川消退期间陆基冰对海平面变化的贡献。此外，这些数据还将对用于各种其他应用的地球物理模型中的关键参数提供重要约束（例如，板块构造学、冰川学和古气候学）。总的来说，这些观察将扩大与历史和当今变化进行比较的时间范围。因此，这项研究有望增加我们对海平面变化驱动机制的理解，并增强我们对21世纪海平面上升的预测。这项研究还将为评估国家在海平面上升和沿海应对方面的危害作出重要和独特的贡献。