In April of this year NASA released findings related to the Earth’s melting ice sheets. Often when the gringa things about climate change, warming temperatures and melting ice sheets, the only thing I consider is how sea levels will rise. It never occurred to me that ice sheet disintegration may result in a more wobbly world.
Think about the traditional children’s toy, the spinning top. It’s a bit like our world. As it slows its spin it begins to wobble. As ice sheets melt and the balance of Earth begins to shift, we will, indeed, experience a global wobble. Scientists officially define this as a “periodic wobble and drift of the poles”. All the gringa wants to know is, “What exactly does this mean for me? Am I going to fall on my patootie trying to walk to my car?”
NASA asserts that over the past sixteen years Antarctica and Greenland, combined, have averaged about 400 billion tons of ice loss annually. Before the year 2000, as Earth spun on its axis it had a gentle drift toward Canada (westward). Because of ice loss, now the drift is about 75 degrees in the opposite direction, eastward. This happens because as ice converts to water and moves elsewhere, the distribution of Earth’s mass changes. What this means exactly is that the location of the North and South poles will change. In other words, Earth’s axis is relocating.
Now, the traditional location of Earth’s North Pole may have to be renamed to the Northeastern Pole. Earth’s axis is like an invisible pin stuck through the Earth from North to South. The Earth spins on the tip of the pin, rotating with a slight wobble that is normal. However, if the geographic location of the Poles change, complete topographical and satellite telemetry systems have to be adjusted to accommodate this change. For the average person, this means that your GPS is going to deliver you to the wrong place!
Scientists have long known that the Poles shift by a few centimeters from time to time as a part of Earth’s natural climate adjustment cycles. But what we are dealing with now is much more dramatic. Experts estimate that the shift is averaging about ten centimeters Eastward annually. Our great-great-grandchildren may have to adjust Christmas stories to have Santa Claus living in Russia or Norway.
Although scientists understand that as ice continues to melt the Earth will adjust by shifting its axis to the place where it has lost mass, even their best predictions are really just a guess. This is an extremely complex problem. It’s not just melting ice sheets that affect the process but also loss of groundwater in above ground reservoirs and underground aquifers (which underground aquifers cannot be accurately measured) as well as glacier melt and glacier movement. Many glaciers float about the ocean as they please.
The Earth’s ice and water storage formula affects polar drift. Yet many of the variables in the formula cannot be measured or can change their individual affect. So, scientists are left scratching their heads, doing the best with what they’ve got, and hazarding their best guess on what humanity can expect.
Ice melt is not the only thing that can bump the North Pole to a different location. Enormous earthquakes and devastating tsunamis can do the job as well. Indonesia’s great earthquake moved the North Pole eastward by about 2.5 centimeters and also lengthened Earth’s day cycle by 2.68 microseconds. No wonder I’ve been so tired lately! The gringa is filled with wonder at how humans remain at the mercy of nature despite all of our technological advances.
Image Credit: www.worldatlas.com