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Comment Otherwise Known As A Jökulhlaup (Score 4, Interesting) 136

Glacier outburst floods are known as "jökulhlaups" in geology, an Icelandic word since it has been the scene of many historic floods of this type.

In 1755 a jökulhlaup from the Katla volcano had a peak flow of up to 400,000 cubic meters/second, about 20 times the flow rate of the Mississippi River, or twice that of the Amazon, making it briefly the largest river in the world.

But that's not the only destructive aspect of Iceland's volcanoes. In 1783 the eruption of the Laki volcano released 14 cubic kilometers of basalt and 1 cubic kilometer of airborne ash. It killed 25% of Iceland's population through poison gas: 500 million tons of hydrogen fluoride and sulfur dioxide were released poisoning the population and the livestock. The fatalities were both from direct poisoning (mostly from the hydrogen fluoride) and later starvation since most of the livestock was killed. The toxic cloud affected much of Europe as well, though not as severely. This eruption also created a three-year long period of unseasonable cold in the northern hemisphere leading to famine killing thousands, and possibly contributing to the French Revolution.

Comment Re:Not new proof of settlement (Score 1) 147

Very true.

This is only one example of a long series of discoveries over the last 40 years. An extensive system of earth works, causeways, and canals have been found along the Xingu river (an Amazon tributary). Large sections of jungle have turned out to be fruit tree orchards that over-grew with forest (which would have happened quite quickly once left untended). The entire Amazonian basin itself was virtually unknown to European civilization until the 20th Century - for most of that time it was outside of the control of colonial and later Brazilian government, being instead controlled by societies of Indians and escaped slaves. Societies of many tens of thousands of Indians, like the Yanomamo, only started being studied by westerners starting in the 1950s and to this day live in areas outside of state administrative control. Discoveries like this are being made all over the Amazonian basin, now that westerners are actually examining it.

Comment Re:According to Macbeth (Score 1) 145

To die, to sleep--
No more--and by a sleep to say we end
The heartache, and the thousand natural shocks
That flesh is heir to. 'Tis a consummation
Devoutly to be wished. To die, to sleep--
To sleep--perchance to dream: ay, there's the rub,
For in that sleep of death what dreams may come
When we have shuffled off this mortal coil,
Must give us pause.

Hamlet's Soliloquy

Comment The Is No One Purpose for Sleep (Score 1) 145

The need for "sleep" (regular periods of markedly reduced activity, distinct from mere rest) is virtually universal across the vertebrate sub-phylum at least, with a last common ancestor 500 million years ago, found in every family (though not necessarily obviously so in every species).

This extraordinary common pattern in creatures with radically different environments and life habits, persisting over such a vast stretch of evolutionary time, alone suggests there is not "one reason" for it, and indeed a lot of research has uncovered many necessary processes associated with sleep, which go hay-wire at different rates when sleep is denied. In fact going without sleep is lethal, usually killing animals faster than starvation.

Evolutionary biology offers a coherent explanation for all of these facts. Periods of inactivity to conserve energy and reduce exposure to predators is an evolutionary advantage, so a branch of evolutionary descent would tend to develop such a pattern if one did not already exist. Once a regular period of reduced activity exists biological processes that are more efficient or effective during periods of inactivity would tend to migrate in timing to coincide with it. Thus many biological processes, related or not, would in time become associated with this "sleep" period in a common pattern of convergent evolution, and the organism would become dependent on sleep periods for many unrelated biological reasons.

Comment Re:Expected /. response (Score 1) 503

For what I hope are obvious reasons, Microsoft cares the most about those users!

And yet, only half of all employees work for large enterprises (according to the Census Bureau), and just about every employee, and lots and lots of non-employees have their own computers at home. So those users, which even you - a self-verified Microsoft pitch-man (to use a polite term) - readily admit are less "cared" about by Microsoft are the large majority of their total user base, and the source of the large majority of its revenues.

Thanks for confirming that only Big Boys get respect and decent treatment from the Redmond Mafia, all rest of us peons are only here to be "harvested".

Comment Re:Labels (Score 1) 112

Saurischians are dinosaurs, dinosaurs are saurischians. Birds are saurischians. Birds are dinosaurs. Since the publication of The Origin of Species, and the flurry of evolutionary classification that took off after it, birds have been recognized as some kind of Archosaur or another. Birds have always been known to have been dinosaurs.

You are certainly correct that the identification of birds with dinosaurs was proposed quite early, but it is going a bit too far to say that was generally "known" to be the case. The "Are Bird's Dinosaurs?" debate, was absolutely a topic of argument for a century and a half, but is really two overlapping debates. The first is the actual descent of birds from fossilized (proposed) ancestors, and the second is a fundamental one for evolutionary classification, how should you group species (i.e. what is a taxon)?

Linnaean taxonomy was based on grouping species by common characteristics, but this created lots of paraphyletic and polyphyletic taxons. A paraphyletic taxon includes an ancestor, but only some of its descendants as member; a polyphyletic taxon excludes the common ancestor of the members and usually some of the other descendants as well (convergent evolution is a common reason for this).

Cladistics, the use of statistical grouping methods (aided by computers), clarified things considerably starting in the 1960s, and then genetic analysis put it into hyperdrive, proving the fundamental correctness of the cladistic approach, and giving it an unambiguous standard of validity. Modern groupings invariably strive to be monophyletic.

Cladisitics actually helped clarify the interpretation of the fossil record for birds so in the 1980s biology came to recognize that a consistent method of classification, combined with a better interpretation of fossil evidence required birds to be classified as a type of dinosaur.

It really is more than a matter of changing labels. This did create a change in understanding about how to think about dinosaurs based on the surviving branch of the taxon, and about the origin and nature of birds.

Comment Re:Metric / Imperial (Score 4, Insightful) 167

Multiples of 3 are just so much more useful in everyday life than multiples of 10. I used the base 12 pica/point system in printing for many years, and always admired how trivially easy it was to calculate layout proportions. The human attention is drawn strongly to things in threes: three panels, three points in an argument, three parts to a story, and many others.

More than just the magic of 3. Since 12 has the three smallest (non-trivial) integer divisors, and four of the five smallest, it is simple to do many proportional (ratio) calculations and measurements. 10 only has two (non-trivial) integer divisors.

This extended to adding 5 and 6 as divisors gives the 360 degree division of the circle, invented by the Sumerians and adopted universally around the Old World (along with their division of the day into 12, then 24 hours, for similar reasons). Utility is proven by use.

Comment Re:What type of solar (Score 1) 504

And we need to build a breeder reactor to reduce the volume of nuclear waste by 2 orders of magnitude.

No we don't, and it doesn't.

Currently nuclear waste volume consists of spent fuel rods which can be stored safely and permanently in dry casks. Currently power reactors need a core change every two years, one core load takes 4 dry casks to store. Dry cask storage takes about 25 square meters per cask (with generous "walk around space"), so that load could be stored in 100 square meters. Over a 50 year period this is only 25 fuel rod loads, or 100 casks, taking up 2500 square meters. Throw in all 100 reactors operating in the U.S., and that is 250,000 square meters, or about 65 acres. This is not a problem that needs "solving". It is already solved.

And reprocessing with breeder reactors does NOT "reduce the volume of nuclear waste by 2 orders of magnitude"! This is a made-up number. What reprocessing can do is remove the long-lived actinides for burning up in special actinide burner reactors (which need not be "breeders"), but the cost of this is very high. Currently the problem nuclear power has is its high capital cost that makes it financially unattractive to build new reactors. For any chance at commercial viability nuclear power must keep the fuel cost part of the system as low as possible. Cheap cask storage is the best option for this, which is why the nuclear industry is opting for it.

Comment Re:What about at night? (Score 4, Informative) 504

What about at night?

Fortunately the wind blows at night. Here is a wind resources map for the United States. Lots and lots of consistently windy areas. Wind is cheaper than solar currently and in nine out the ten nations that top the renewable energy charts, there is more wind capacity than solar, and this is likely to remain the case.

With the use of high voltage DC transmission lines (a technology that has been in use since 1930) electricity can be shipped coast to coast with minor losses. 800 KV lines can transport electricity from one coast to the other with about the same losses as existing grids, about 6%. Constructing a national long distance electrical "highway" makes most of the "problems" perceived with renewable energy disappear. Just like now, there is not going to be just one source of power in the future, so solar does not have to do it all.

Even is solar "only" supplies the daytime peak load, this is half of the total electricity demand. In North America it is convenient that 40% of the entire U.S. population lives on the Eastern Seaboard, so that when it has its evening demand peak, the sunny west is three hours earlier and would still be producing a lot of solar electricity. Then there are proven power storage technologies like pumped water storage. Just considering existing pumped storage capacity, and capacity expansion that has applied for permits, we are looking at 76.7 GW of PS capacity in the U.S. which is 7.5% of U.S. peak electricity demand.

Comment Re: The Cantina (Score 1) 304

Han didn't shoot first.

Here's the order of operations:

Han shoots Greedo.

Greedo never fires, because Han shot him, and Greedo is dead.

Of course. Which it is so utterly stupid and insulting to the audience to have Greedo shoot first. Han would have been dead. They were sitting across from each other at an effing table for X's sake!

Comment Re:Keep it original... (Score 4, Insightful) 304

>> Unlikely. Lucas destroyed the originals when he made the Special Editions.

Whut? Why TF would he do that?

Because he is God of the Star Wars Universe and mere things like preservation of significant historical documents, and the desires of the fan base are nothing to him.

Lucas is a brilliant businessman, his career with LucasFilm and ILM speak for themselves. But his talents and wisdom as a director and creative force are extremely uneven, and he seems unable to consider the views of others, no matter how well founded and insightful. Again, his post Star Wars career speaks for itself. I think he was extremely lucky to have an astonishingly talented team working with him when he made Star Wars, and he was also lucky that he had to collaborate and let others make key decisions - he was not so successful at that point that he could be creative dictator.

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