Mag­netic north rac­ing away to­ward Rus­sia

Winnipeg Free Press - Section H - - THE WEST - By Ken Kaye

FORT LAUD­ERDALE, Fla. — Mag­netic north, the point at the top of the Earth that de­ter­mines com­pass head­ings, is shift­ing its po­si­tion about 60 kilo­me­tres a year. In ge­o­logic terms, it’s rac­ing from the Arc­tic Ocean near Canada to­ward Rus­sia.

As a re­sult, ev­ery­one who uses a com­pass, even as a backup to mod­ern GPS nav­i­ga­tion sys­tems, needs to be aware of the shift, make ad­just­ments or ob­tain up­dated charts to en­sure they get where they in­tend to go, authorities say. That in­cludes pi­lots, boaters and even hikers.

“You could end up a few miles off or a cou­ple hun­dred miles off, de­pend­ing how far you’re go­ing,” said Matthew Brock, a tech­ni­cian with Laud­erdale Speedome­ter and Com­pass, a Fort Laud­erdale com­pany that re­pairs com­passes.

Al­though the mag­netic shift has lit­tle ef­fect on the av­er­age per­son and presents no dan­ger to the Earth over­all, it is cost­ing the avi­a­tion and marine in­dus­tries mil­lions of dol­lars to up­grade nav­i­ga­tional sys­tems and charts.

The Earth’s core of hot liq­uid iron is con­stantly mov­ing. That mo­tion, com­bined with forces such as the Earth’s ro­ta­tion, dic­tate the po­si­tion of mag­netic north, not to be con­fused with geo­graphic north, or the North Pole.

“Mag­netic north is shift­ing all the time; it’s a con­tin­u­ous process, not an event,” said Jef­frey Love, a geo­physi­cist with the U.S. Ge­o­log­i­cal Sur­vey ge­o­mag­netism pro­gram in Golden, Colo.

Over the past cen­tury, the shift has gained speed. It went from creep­ing as slow as 12 kilo­me­tres a year in the early 1900s to more than 50 kilo­me­tres a year in the 2000s. How­ever, that ac­cel­er­a­tion is also part of a nat­u­ral cy­cle, Love said.

“In 10 to 20 years from now, it might be slow­ing down,” he said.

Cur­rently, the shift cre­ates about a one de­gree dif­fer­ence in com­pass direc­tion ev­ery five years, Love said.

Be­cause GPS nav­i­ga­tion draws on satel­lites, it has no re­liance on mag­netic north. On the other hand, satel­lites and GPS sys­tems can mal­func­tion. For that rea­son, Tom Cartier rec­om­mends that all pi­lots and boaters keep a com­pass handy as backup.

“The mag­netic com­pass is what gets you home in your boat or plane when ev­ery­thing else quits,” said Cartier, a se­nior deck in­struc­tor at Mar­itime Pro­fes­sional Train­ing in Fort Laud­erdale. “It’s a very, very valu­able piece of equip­ment.”

Cartier said large ships and planes have so­phis­ti­cated elec­tronic nav­i­ga­tion sys­tems, but the vast ma­jor­ity of small boats and planes have mag­netic com­passes and rely on them heav­ily.

The oil in­dus­try also re­lies on know­ing the ex­act po­si­tion of mag­netic north, as com­pa­nies use a de­vice sim­i­lar to a com­pass to de­ter­mine what an­gle to drill into the earth, Love said.

“They don’t drill straight down,” he said. “They need to ori­ent their drill bits to know which way they’re go­ing.”

Many mo­bile com­pa­nies equip smart phones with mag­ne­tome­ters, al­low­ing their cus­tomers to see what direc­tion they’re head­ing. Those phones are likely to have a de­vice that ad­justs for the shift in mag­netic north, said Manoj Nair, a re­search sci­en­tist with the Na­tional Oceanic and At­mo­spheric Ad­min­is­tra­tion’s Geo­phys­i­cal Data Cen­ter.

Hu­mans aren’t the only ones af­fected by mag­netic north. Birds that fly south for the win­ter and some sea tur­tles that mi­grate from Africa to South Amer­ica must learn to ad­just their senses so they end up mi­grat­ing in the right direc­tion, Love said.

“Some sea tur­tles live for a long pe­riod of time, up to 100 years,” he said. “They have to ac­com­mo­date the change in the mag­netic field, be­cause it changes sub­stan­tially over 100 years.”

— Sun Sen­tinel

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