This one-year award supports U.S.-Sweden-Norway cooperative research between James Davis of the Smithsonian's Astrophysics Observatory in Cambridge, Massachusetts and Bernt O. Ronnang of the Onsala Space Observatory, Chalmers University of Technology, Onsala, Sweden. The objective of the research is to take measurements of three-dimensional crustal motion at locations in Sweden and Norway (Fennoscandia). The estimates of crustal velocity will be used to determine viscosity of the Earth's mantle beneath Fennoscandia and to correct estimates of sea-level change associated with local vertical crustal motion. Knowledge of the mantle's viscosity is required for understanding mantle convection, the driving force of plate tectonic motion. The estimates of sea-level change for crustal motion is required for determining global sea-level change, an important gauge of global warming. Satellite surveying techniques are to be employed for estimating crustal velocity. The project takes advantage of complementary expertise of the U.S. and Swedish research groups and Swedish coordination with the Nordic Council funding agencies. The U.S. investigators have extensive experience in the processing of space geodetic data and using this data to estimate geophysical parameters. This is complemented by the Swedish group's knowledge of the region. They will plan the surveys, the site reconnaissance and coordinate the effort with the Nordic Council.
