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Comment Re:So is it... (Score 2) 49

When they say "pre-industrial levels", when do you think they mean? The 19th century (even though the industrial revolution was well underway), usually 1890 specifically.

What year is used depends entirely on the study. Some start at the advent of satellite measurements, some at the advent of modern ground-based measurements, some with the era of semi-reliable ground-based measurements, some incorporate further back with more fragmentary measurements, and others use proxies - some recent proxies from 200, 300, 400 etc years ago, others thousands, tens of thousands, hundreds, millions of years ago or more. There is no single timeframe that is examined. Numerous studies evaluate each different source, and the different proxies are commonly plotted out relative to each other.

Comment Re:Indeed (Score 2) 49

It's hard to overstate how bad it would be. Iceland doesn't just get glaciated in ice ages, it gets catastrophically glaciated. As in "mass kills almost all of our plant species". That's why there's currently no native conifers even though there used to be, for example - virtually the whole island ends up under an extremely thick sheet of ice.

Of course, a shorter localized ice age, in an otherwise warming world, isn't as bad as a Milankovitch Cycle ice age. But it'd be pretty awful for us. Right now, we're benefiting from a warming world (though losing our glaciers and regularly getting annoying new insect species which previously couldn't survive here :P). Our growing reason is so short, and the difference between our winter and summer temperatures so small, that even a small amount of warming drastically lengthens our growing season, and makes a vast difference to how well things can grow in it.

Comment Re:So Iceland is worried that it may become ... (Score 3, Informative) 49

It does get overplayed though, with people acting like there was no reason to name Iceland "Ísland" and no reason to name Greenland "Grænland". There's plenty of ice here (much of the middle of the country doesn't melt until quite late in the year, and settlers approaching from the south and east sailed past the huge terminal glaciers of Vatnajökull), and the places that were settled in Greenland weren't all that different from e.g. Vestfir(th)ir. Grænland was chosen as a name to advertise it, but it's not like it was some sort of lie - most new settlements, even random villages wherever you are, are generally given pleasing names to try to attract people.

Also, Iceland got its name due to Flóki "Raven" Vilgerðarson, the viking-discoverer of Iceland (though the Irish already knew of Iceland). He had a clever trick to find islands, which was having ravens (land birds) on his boat; they'd fly up, look for land, and if they spotted it, beeline for it, but otherwise had no choice but to return to the boat. Ravens are quite large, black birds and thus easily visible to track from a boat. Anyway, his first winter at Bar(th)arströnd was abnormally cold, and there was sea ice visible offshore (something quite rare in Iceland), so he chose the name "Ísland".

Comment Re:So Iceland is worried that it may become ... (Score 2) 49

It's "ís" (accented), and is pronounced "eece" :) "Eece-land" (land said like with a British accent, not an American one)

Fun fact: while ís does indeed mean "ice", it's not the colloquial word for ice - like, if you want ice at a restaurant, you ask for "klaki" (people sometimes jokingly refer to being in Iceland as "á klakanum" ("on the ice" ;) ). "Ís" these days is used as short for "rjómaís", lit. "cream-ice", aka ice cream - if you ask for "ís" at a restaurant, you'll get ice cream.

So in modern parliance, the country is "Ice Cream Land". ;) (Honestly, our ice cream is really good here - try the bilberry ice cream at Erpssta(th)ir for example :) )

Comment Re:So is it... (Score 1) 49

Do you think it is interesting that the century during which an ice age was ending is the one used as a baseline for climate analysis?

https://en.wikipedia.org/wiki/...

"The Little Ice Age (LIA) was a period of regional cooling, particularly pronounced in the North Atlantic region.[2] It was not a true ice age of global extent.[3] "

Literally right at the top of the article.

Also, for the record, there is no single "baseline timeperiod for climate analysis".

Comment Re:Woke AI education is now a thing :o (Score 5, Insightful) 62

"Woke" simply means "I'm conservative, and the thing I'm calling 'Woke' is something that I hate". It has no well-defined meaning beyond that. I've heard things as diverse as "the concept of the Metaverse" and "removing copyrighted content so you don't get sued" described as "woke".

Comment Re:Poor design, not impossible (Score 0) 89

A practical issue with a circle is that it is not a circle until it is finished,

That's not the reason at all, AFAIK. The reasoning is, okay, we want people to be able to move from one place to some distance place in the city at the maximum comfortable speed, which is limited by G-forces. You have some guaranteed G-forces from first accelerating and then decelerating. But if it's linear, that's your only G forces. If it's curved, however, you also have radial G-forces.

The Line's train going from one end to the other (170km) nonstop is supposed to do it in 20 minutes, aka with a mean speed of ~510 kph. Let's say a peak of 800 kph. Now if we shape that 170km into a circle, that's 54km diameter, 27km radius. From the centripetal force formula a=v^2/r, that's 222,22...^2 / 27000 ~= 1,83 m/s^2, or a constant ~0,2g to the side. This is on top of the G-forces from your acceleration and deceleration. You can probably deal with ~0,2g in a train if everyone is seated without much discomfort, though it's double what's acceptable for standing passengers. But you can eliminate that if the city is linear (at the cost of increasing the mean distance that the average person has to travel to go from one arbitrary point in the city to another)

That's not to defend this concept. Because the city doesn't need to be 170km long; you can just made it more 2d and have the distances be vastly shorter (at the cost of just needing some extra lateral travel within the city). Honestly, if I were building a "designer" city from the ground up, I'd use a PRT (Personal Rapid Transit) system rather than trying to make it super-elongated.

Comment Re:“You do realise the earth is spinning?&am (Score 1) 89

What got me is that I don't see why this isn't readily resolved by active damping, the same systems that many tall towers now use to resist earthquakes or resonant wind forces. Big heavy weight at the top (or in this case the bottom) hooked up to actuators that make it move in an inverse direction to the sway.

Again, this is not to defend this colossal waste of money. I just don't see why there aren't ready solutions for this specific problem.

Comment Re:C'mon, Saudi (Score 2) 89

Agreed - but that said, there are space elevator alternatives, like the Lofstrom Loop / Launch Loop, which at least theoretically can be built with modern materials (and have far better properties anyway - not latitude-constrained, provides dV, vastly higher throughput, far more efficient, stores energy / can add cheap energy at off-peak times, etc). One could always "waste" money on them trying something new :)

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