Jan 262023
 

“Stop the presses! The Earth’s core stopped spinning! In fact it is now spinning backwards!”

Well, that’s pretty much how much of the popular press handled a recent article, published in Nature Geoscience, under the far less pretentious title, “Multidecadal variation of the Earth’s inner-core rotation”.

And indeed, the first half-sentence in the abstract says it all (emphasis mine): “Differential rotation of Earth’s inner core relative to the mantle“.

It’s not like the core stopped spinning. It’s just that the core is sometimes spinning slightly faster, sometimes spinning slightly slower than the mantle, an oscillatory pattern that has to do with the complex interaction between the two.

How much faster/slower? Don’t expect anything dramatic. At most a few degrees a year, but more likely, just a small fraction of a degree a year. So even if the ~70-year cycle (deduced by the authors of the recent article — there are other estimates) is valid, the core would only get ahead, or behind, the mantle by just a few degrees before it slows down or catches up again.

And this is what supposedly happened: the core was slowing down until a few years ago, its rotation came to be in sync with that of the mantle. Slowing down further, it’s now falling ever so slightly behind, only to catch up again, presumably, a few decades from now.

The way it is misleadingly presented in the media and the degree to which it is sensationalized demonstrate that we live in the era of hype.

 Posted by at 6:21 pm
Dec 182012
 

I came across this a while back; one of the most astonishing places on Earth, near the village of Derweze (also spelled as Darvaza) in Turkmenistan.

Situated in an already lunar looking landscape in the Karakum desert, there is a crater that is unlike anything on the real Moon: it’s a crater full of fire. The ground collapsed here in 1971 after Soviet geologists were drilling for oil and found natural gas instead. The gas was ignited in the hope that it would safely burn off in days… it has been burning ever since.

 Posted by at 8:13 am
Aug 022011
 

Finally, a voice of reason.

I just read an opinion piece in New Scientist by Erle Ellis. His message is simple: Welcome to the Anthropocene. Ellis believes that the geological epoch called the Holocene is over; the landscape of the Earth has been altered irreversibly by humans, but not all such change is bad or unwelcome. In any case, there is no turning back. The question is not how to undo what we have done, but how to create a better, more sustainable Anthropocene, as we have become the creators, engineers, and stewards of this world.

This has also been my opinion for a long time. Humans are no less “natural” than apes, ants, whales, or trees. By extension, a skyscraper or a factory are no less natural than an anthill or a bird’s nest. However, it has happened in the past that a species overwhelmed and destroyed the environment in which it once thrived. Humans can suffer the same fate… except that we do possess oversize brains and the ability to plan ahead in the long term. What we need is not some romantic notion of a “pristine planet”, but to learn how to manage a planet of finite resources that is dominated, and irreversibly altered, by our presence.

 Posted by at 12:27 pm
Jun 232010
 

Ouch! That was quite the rumble. Enough to freak out all the cats. This is the third significant earthquake I experienced here in Ottawa; it may not have been the strongest as measured by instruments, but it certainly felt the most, hmmm, “hostile” sounds like the right word.

 Posted by at 7:49 pm