AMMONITE TAKES THE TITLE

F irst-time entry Ammonite – representing the Royal Nomuka Yacht Club of Tonga – reigned supreme at this year’s NZ Millennium Cup in the Bay of Islands in January. The 24.72m luxury yacht was built in South Africa by Southern Wind Shipyard and delivered i

Daniel Baker is a director at the Laboratory for Atmospheric and Space Physics at the University of Colorado. He says the Earth’s magnetic field has weakened by some 15 per cent over the last two centuries, and this may be a precursor to a pole reversal.

Earths’ geological record shows that magnetic pole-swapping is a relatively regular phenomenon – every 200,000 or 300,000 years – but mankind has never experienced one. The last flip was about 780,000 years ago. So the next one is a tad overdue, and the recent weakening in the magnetic field might herald its imminent arrival.

Earth’s molten core generates its magnetic field and creates the ‘magnetosphere’ that serves as a barrier against devastating solar winds, cosmic particles and ultraviolet B rays. Results of a pole swap may be scientifically intriguing, but they’re definitely not appealing.

They include the solar winds punching holes through the Earth’s ozone layer, removing the protection we currently enjoy from the devastating barrage of galactic nasties. This would knock out power grids, affect weather, change the climate and increase cancer rates. Some areas of the planet, warns Baker, could become ‘uninhabitable’.

Anyone who’s done a little bluewater sailing in the higher latitudes will be familiar with ‘magnetic variation’ – the difference between True North and Magnetic North. This changes annually, and it varies considerably depending on where you are – and it needs to be factored into your navigation.

Variation and navigation would become incomprehensible in a pole-swap scenario, but chances are this is likely to be the least of mankind’s problems.