Why diet when you can move to Manitoba?

This week's installment of Science provides a peculiar way of dropping a few pounds (ok, well...maybe a few thousandths of a pound): move to Manitoba.  A joint research team from Harvard and the University of Toronto has helped to constrain an abhorrent gravity anomaly over the Hudson's Bay region using data obtained from the Gravity Recovery and Climate Experiment (GRACE) satellite mission.

Although a few other hypotheses have proposed mechanisms for this apparent lower gravity, none were entirely sufficient in doing so.  It appears the Laurentian Ice sheet, upon melting after the last glacial maximum some 15-20 thousand years ago, left an imprint in the underlying continent (likened to a rather hefty individual getting out of a plush leather couch).  Just as the leather couch requires time to re-acclimate to its previous state, so does the continental land mass.  This process, termed isostatic rebound, is responsible for the slightly lower gravity over the region.