Monitoring the temporal changes in the gravity field, oceans, land water and ice masses in North America by means of integrated satellite data

在过去的几十年里，我们目睹了与气温上升有关的气候系统的前所未有的变化。冰原、冰川和多年海冰一直在减少，海平面在上升，永久冻土的南部边界在加拿大向北移动。洪水、干旱和水资源短缺更加频繁和严重，北冰洋在夏季正慢慢变得无冰。据预测，到本世纪末，全球气温将上升1.5摄氏度至3摄氏度，海平面将上升60厘米，预计将出现更多极端天气事件、严重的沿海淹没和水资源枯竭。这些变化威胁着基础设施、交通、栖息地、生态系统以及日常生活和商业活动。根据《巴黎协定》，加拿大有责任评估、减轻和适应这种环境和社会影响。在全球、区域和国家尺度上，地球轨道卫星持续的长期观测序列是监测、模拟和预测这种变化及其造成的自然灾害的宝贵工具。拟议的研究计划旨在通过量化加拿大和北美（NA）的这些影响，从而有助于实现这一长期目标，从而能够对其进行适当评估，并使政府能够做出明智的决策，以减轻其影响。这将通过整合已有几十年的多个重力和测高卫星任务（GOCE， GRACE, Swarm, ERS1tes）的观测结果来实现，这将是该研究计划的一个关键方面。第二个目标是利用卫星测高数据，结合卫星重力观测，确定冰面随时间的变化和质量损失，并估计它们对海平面上升的贡献。海冰的消退也将被研究，因为如果持续下去，它将产生巨大的经济影响，因为它将使加拿大北极地区的航行和资源勘探成为可能。第三个目标是研究海洋的平均海面如何随时间变化，这是了解沿海淹没、风暴潮、洪水等灾害的重要因素，特别是在加拿大沿海地区。对加拿大主要湖泊和河流水位的监测也将进行调查。最后一个目标是确定NA上的总时间质量再分布及其对大地测量和地球物理应用的影响

In the past few decades, we have witnessed unprecedented changes in the climate system related to rising temperatures. Ice sheets, glaciers and multi-year sea ice have been declining, sea levels are rising, and the permafrost's southern limit is moving northward in Canada. Floods, droughts, and water shortages are more frequent and more severe, and the Arctic Ocean is slowly becoming ice-free in the summer. With projections for global warming of 1.5C to 3C and for rising sea levels of up to 60 cm by the end of the century, more extreme weather events, severe coastal inundation and depletion of water resources are forecasted. Such changes threaten infrastructure, transportation, habitats, ecosystems, as well as daily living and commercial activities. With the Paris agreement, Canada has a responsibility to assess, mitigate, and adapt to such environmental and social impacts. On global, regional and national scales, sustained long-term time series of observations from Earth-orbiting satellites are an invaluable tool for monitoring, modeling and predicting such changes, and the natural hazards they cause. The proposed research program aims to contribute to this long-term goal by quantifying these effects in Canada and North America (NA), which will then allow their proper assessment and enable informed government decisions for their mitigation. This will be achieved by integrating observations from multiple gravity and altimetry satellite missions available already for several decades (GOCE, GRACE, Swarm, ERS1tes will be a key aspect of this research program. The second objective is to use satellite altimetry data, combined with satellite gravity observations, to determine the ice surface changes and mass losses over time, and estimate their contribution to the rise of the sea level. Retreating sea ice will also be studied because, if sustained, it will have a tremendous economic impact since it will make navigation and resource exploration possible in the Arctic regions of Canada. The third objective is to study how the mean sea surface of the oceans changes over time an important factor for understanding hazards like coastal inundation, storm surges, flooding in particular in the coastal regions of Canada. The monitoring of the water levels of major lakes and rivers in Canada will also be investigated. The last objective is to determine the total temporal mass redistribution over NA, and its effect on geodetic and geophysical applications.**