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

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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.**