The New Scientist. Excerpts:
Lopsided growth of the Earth's core could explain why its magnetic field reverses direction every few thousand years. If it happened now, we would be exposed to solar winds capable of knocking out global communications and power grids.
One side of Earth's solid inner core grows slightly while the other half melts. Peter Olson and Renaud Deguen of Johns Hopkins University in Baltimore, Maryland, used numerical modelling to establish that the axis of Earth's magnetic field lies in the growing hemisphere – a finding that suggests shifts in the field are connected to growth of the inner core.
There are signs that the next switch may be under way: rapid movements of the field's axis to the east in the last few hundred years may be a precursor to the north and south poles trading places, the researchers speculate.
(..)
"They are suggesting very cautiously that maybe this rapid change is somehow suggestive of us going into a reversal event," he says. "You could imagine if the field were to collapse it would have disastrous consequences for communication systems and power grids."
Wouldn't it be nice to know that these types of considerations are taken seriously and given high priority? That won't happen soon, or maybe ever, so don't hold your breath. Still, wouldn't it be nice if they were?
Lopsided growth of the Earth's core could explain why its magnetic field reverses direction every few thousand years. If it happened now, we would be exposed to solar winds capable of knocking out global communications and power grids.
One side of Earth's solid inner core grows slightly while the other half melts. Peter Olson and Renaud Deguen of Johns Hopkins University in Baltimore, Maryland, used numerical modelling to establish that the axis of Earth's magnetic field lies in the growing hemisphere – a finding that suggests shifts in the field are connected to growth of the inner core.
There are signs that the next switch may be under way: rapid movements of the field's axis to the east in the last few hundred years may be a precursor to the north and south poles trading places, the researchers speculate.
(..)
"They are suggesting very cautiously that maybe this rapid change is somehow suggestive of us going into a reversal event," he says. "You could imagine if the field were to collapse it would have disastrous consequences for communication systems and power grids."
Wouldn't it be nice to know that these types of considerations are taken seriously and given high priority? That won't happen soon, or maybe ever, so don't hold your breath. Still, wouldn't it be nice if they were?
Posts
No comments:
Post a Comment