“The loss of ice from West Antarctica between 2009 and 2012 caused a dip in the gravity field over the region,” writes the ESA, whose GOCE satellite measured the change. Apparently, melting billions of tons of ice year after year has implications that would make even Isaac Newton blanch To be fair, the change in gravity is very small. It’s not like you’ll float off into outer space.
The biggest implication is the new measurements confirm global warming is changing the Antarctic in fundamental ways. Earlier this year, a separate team of scientists announced that major West Antarctic glaciers have begun an “unstoppable” “collapse,” committing global sea levels to a rise of several meters over the next few hundred years.
Though we all learned in high school physics that gravity is a constant, it actually varies slightly depending on where you are on the Earth’s surface and the density of the rock (or, in this case, ice) beneath your feet. During a four-year mission, the ESA satellite mapped these changes in unprecedented detail and was able to detect a significant decrease in the region of Antarctica where land ice is melting fastest.