Hold On, Santa – Earth’s Poles are Moving Quickly
Santa Claus has always lived on shifting ground. The Earth’s geographic poles move around a bit every year depending on the distribution of mass, creating a kind of wobbling effect, which we fortunately don’t feel. Now a group of researchers at the University of Texas, Austin have noted an acceleration in the movement of the poles, and they attribute it to climate change.
Between 1982 and 2005, the North Pole moved about six centimeters every year in the direction of Labrador, Canada –unlikely to be pulled over for speeding, right? But in 2005, the pole abruptly changed direction, veering East towards Greenland and almost doubling its speed. Looking for explanations, the research team turned to a plethora of geophysical data about the region, and one observation was inescapable: at the same time the pole was speeding up, the rate of Arctic sea ice melt was increasing.
They took a closer look at information from the Gravity Recovery and Climate Experiment (GRACE) run by NASA. GRACE measures changes in the Earth’s gravity field, which also changes over time, with the potential to allow researchers to track changes in the distribution of mass. Using GRACE, they were able to follow sea ice melt, and they noted that, as predicted, when the Earth lost mass in one area, it naturally tilted slightly in that direction.
Since Greenland’s ice sheet has been retreating at a shocking rate, it’s no surprise that the geographic pole has been moving that way recently, and that the movement has sped up. Their research shows that it’s possible to doublecheck data on sea ice melt by looking at the position of the pole, creating a confirmation method. Being able to confirm data via an independent method is tremendously helpful in science, where much can ride on the outcome of studies and researchers want to make sure they have their facts right.
Furthermore, this study, the researchers posit, will help bridge a gap between GRACE and the followup mission, GRACE II, which isn’t scheduled to launch until 2020. Additionally, now that the researchers have established a baseline and refined their data, it might be possible to perform a lookback study to improve estimates of ice loss before satellite monitoring was available. That’s more good news that will make it easier to make accurate comparisons when looking at sea ice then and now.
This research is fascinating and it has important implications for future studies, showing how a symptom of climate change can in turn be used as a tool to measure specific aspects of climate change. While migrations of the geographic pole don’t have a big impact on the daily lives of most of us, the underlying cause, melting sea ice and rising sea levels, most definitely does. The researchers claim that 90% of the movement of the Earth’s poles can be attributed to climate change, illustrating yet another phenomenon hitched to this runaway environmental train.
Photo credit: Staff Sgt. Joseph Burke and Sgt. Brandi Manuel from the 7th Sustainment Brigade, XVIII Airborne Corps reenlist at the South Pole, February 2012. US Army