The latest edition of the Earth's magnetic field map, which serves as a reference for ships and aircraft to determine direction, has been released. According to the new map, the magnetic North Pole has shifted from northern Canada toward Siberia over the past five years. It also indicates that the locations of blackout areas, where compasses do not function, at both poles have moved during the same period.
The National Oceanic and Atmospheric Administration (NOAA) and the British Geological Survey (BGS) released the latest edition of the World Magnetic Model (WMM2025) on the 17th.
NOAA said, "The WMM released this time is a kind of modern edition of the Earth's magnetic field map," adding, "New information will be reflected in all military and civilian aircraft, ships, submarines, and Global Positioning Systems (GPS)."
◇ The magnetic North Pole is moving from Canada toward Siberia
The Earth's magnetic field has slowly changed since the planet's formation. As tectonic plates rise along mid-ocean ridges and meet seawater, the magnetic field assumes a consistent value. These slowly moving tectonic plates act like tape recorders, preserving past magnetic field strength and direction information. Scientists utilize this data to track changes in the strength of the Earth's magnetic field over 160 million years, including geomagnetic reversals where the north and south poles switch places.
According to scientists, there are two concepts of north: "True North" which indicates geographical north, and "Magnetic North" which is the direction the compass needle points. Magnetic North changes position when the magnetic field shifts. The angle between Magnetic North and True North also changes over time, and the distance can be as much as 1,000 kilometers. The situation is the same for the South Pole, which is located opposite the North Pole.
The United States and the United Kingdom have developed the World Magnetic Model (WMM), which contains continuously changing information about the Earth's magnetic field. This magnetic map illustrates significant changes in the Earth's magnetic field over time.
The newly released magnetic field map shows that over the past five years, the magnetic North Pole has moved from Canada toward Siberia. The Earth's magnetic field is generated by the rotation and convection of liquid iron and nickel in the outer core. Scientists have observed that the magnetic North Pole has shifted toward Siberia due to increased convection activity underground in Siberia over the past 20 years.
In 2007, Canadian and French researchers revealed that the magnetic North Pole was moving north-northwest at a rate of about 55 kilometers per year. The British Geological Survey identified in its analysis that the North Pole rapidly moved toward Siberia over 20 years, then suddenly decreased its speed from 50 kilometers to 35 kilometers per year five years ago.
Scientists regard the reduction in the speed of this migration of the magnetic North Pole as a very unusual phenomenon. William Brown, a researcher at the British Geological Survey and an expert on the Earth's magnetic field, noted, "Magnetic North has been moving slowly around the vicinity of Canada since the 1500s, and the current movement is unprecedented."
◇ Impact on aircraft and ship operations, runway numbers also changing
The WMM is used as a standard model by internationally recognized authorities in navigation, including the Federal Aviation Administration, the Ministry of National Defense, the North Atlantic Treaty Organization (NATO), the International Hydrographic Organization, and the United Kingdom's Hydrographic Office. It plays a critical role in ensuring that current navigation technologies function correctly. An accurate magnetic field model is essential for satellite navigation. If the magnetic field model is not properly reflected, errors may occur in satellite positioning, affecting communication, weather forecasting, and Global Positioning System (GPS) services.
Navigation system experts point out that if the newly changed Earth's magnetic field is not reflected, long-distance traveling aircraft and ships may not reach their destinations. A representative from the British Geological Survey, in an interview with Interesting Engineering, said, "If you plan to travel 8,500 kilometers by sled from a house in South Africa to a snow-covered roof of a house in the UK while using previously referenced information, even a 1-degree error could lead you to an incorrect location about 150 kilometers away." The United States and the United Kingdom also update and announce the accuracy of the Earth's magnetic field map every five years.
Changes in the Earth's magnetic field are also leading to renaming of runways in high-latitude regions. According to the Federal Aviation Administration (FAA), airport runways are labeled with compass heading runway numbers. Runway numbers range from 01 to 36 and represent the magnetic heading in degrees divided by 10. For example, runway number 09 indicates east (90°), number 18 indicates south (180°), number 27 indicates west (270°), and number 36 indicates north. However, since the magnetic movement occurs more rapidly near the poles, high-latitude airports are required to change their names more frequently than those closer to the equator. Fairbanks International Airport in Alaska changed its runway name from 1L-19R to 2L-20R in 2009. The airport indicated that it will have to update its name again by 2033 to reflect the speed of changes in the Earth's magnetic field.
◇ 10 times more precise magnetic field map released
The new magnetic field map also reflects the new locations of blackout areas near the magnetic poles. Blackout areas indicate regions where the compass may not function accurately and where the Earth's magnetic field cannot be used for navigation.
The United States and the United Kingdom also released a higher-resolution version of the World Magnetic Model, the high-resolution World Magnetic Model (WMMHR2025), for the first time this year. This version provides magnetic field direction with much higher precision at 300 kilometers, improved from the standard spatial resolution of 3,300 kilometers at the equator. Officials expect this 10 times more precise map will significantly change the functioning of compasses and navigation systems.
There are concerns that errors may arise in smartphones or vehicle navigation systems using existing magnetic maps. However, experts state that smartphone maps and GPS-based applications will not need to worry too much as service providers will carry out necessary corrections.
The reversal phenomenon, where the North and South magnetic poles switch places, is still slowly occurring. Some have raised concerns that a sudden geomagnetic reversal could lead to significant changes in the Earth's environment. However, scientists state that such changes in the magnetic field do not pose short-term threats to the Earth's environment or humanity.
Reference materials
NOAA (2024), https://www.ncei.noaa.gov/news/world-magnetic-model-2025-released
NOAA (2019), https://www.ncei.noaa.gov/news/world-magnetic-model-out-cycle-release