We have Earth’s churning metallic interior to thank for the magnetic field that keeps us safe from the harsh radiation of space, but it’s churning a little faster than expected lately. That means the magnetic pole is wobbling around, causing various navigation issues across the globe. Luckily, there’s a model that corrects for this wobble. Unluckily, a crucial update to the magnetic pole model is delayed because of the US government shutdown. As a result, navigation on Earth is getting increasingly inaccurate.

You may think of the north pole as a geographic location, and that’s true — there is a geographic north pole that doesn’t move. However, there’s also a magnetic north pole that usually drifts about 9.3 miles (15 kilometers) per year. However, the rate of magnetic slippage has increased dramatically in the last few years. Beginning in 2014, the pole has moved an average of 34 miles (55 kilometers) each year.

If all you want to know is the heading of true magnetic north, the shifting pole doesn’t matter much — your compass still points the way. However, if you want to use that heading on top of a map, changes in the pole can screw up navigation. The World Magnetic Model (WMM) provides a correction for the pole shift, but that model is managed by the National Oceanic and Atmospheric Administration (NOAA). With the government shutdown in effect for almost a month, no one is there to update the model.

The last WMM update came in 2015, but as of last year, the model was already tremendously outdated. Because of the increasing pole shift, a major update to the WMM was due on January 15th. The new WMM would have taken into account the last three years of scientific data, including a powerful geomagnetic pulse under South America in 2016. The update didn’t happen, and it won’t until the US government re-opens.

Thankfully, navigation is no longer completely reliant on compass headings, but it’s still an important factor for organizations like NATO, the UK Ministry of Defence, and the US Department of Defense. Your smartphone also uses a compass to determine your orientation. The error in matching magnetic north to a map is more severe the closer you are to the pole. Near the equator, the error is tiny. In the North Sea, it might make a difference.

The pole is currently drifting toward Siberia by a few kilometers per month. The longer we go without a WMM, the more out of sync navigation will get.

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