Wikipedia:Reference desk/Archives/Science/2017 January 30

From Wikipedia, the free encyclopedia
Science desk
< January 29 << Dec | January | Feb >> January 31 >
Welcome to the Wikipedia Science Reference Desk Archives
The page you are currently viewing is an archive page. While you can leave answers for any questions shown below, please ask new questions on one of the current reference desk pages.


January 30[edit]

Toulouse botanical gardens[edit]

Jardin des Plantes, Toulouse and Jardin botanique Henri Gaussen are distinct botanical gardens, aren't they? --Djadjko (talk) 02:47, 30 January 2017 (UTC)[reply]

Actually, I'm looking at Google Maps and it shows them as one and the same. (Jardin Royal is a separate botanical garden, though, being on the other side of the street.) 2601:646:8E01:7E0B:904E:8E2E:48D1:CC6E (talk) 03:12, 30 January 2017 (UTC)[reply]
Nevertheless, it appears they are different; but they are adjacent, with the Henri Gaussen garden located along the northwest side of the Jardin des Plantes. Admission to the Jardin des Plantes is free, as you can also confirm from its open-style entrances. Admission to the Henri Gaussen garden, however, is included when you pay to see the Toulouse Museum: see here (bottom of page, under "billetterie") or here (right side of page 2, bottom of box). The coordinates in Wikipedia for the two places confirm their relative positions. I think the articles about both gardens (in both English and French) should clarify the relationship between them. --76.71.6.254 (talk) 09:31, 30 January 2017 (UTC)[reply]

Are wind patterns guaranteed not to change[edit]

Imagine you are considering an investment on a wind farm in a particular location (say, West Texas). Is it possible that global wind pattern changes make the wind farm obsolete before the turbines become obsolete? Thanks! Brusegadi (talk) 05:58, 30 January 2017 (UTC)[reply]

Where weather is concerned, nothing is guaranteed. But weather data can suggest trends. ←Baseball Bugs What's up, Doc? carrots→ 06:18, 30 January 2017 (UTC)[reply]
You might check the global warming article to see if that is predicted to change global wind patterns. Loraof (talk) 16:47, 30 January 2017 (UTC)[reply]
No, there is no guarantee of wind patterns persisting, yes, it is possible that wind patterns may shift significantly at some locations. From the IPCC report (2007)[1] "Mid-latitude westerly winds have strengthened in both hemispheres since the 1960s." Also "Changes in sea surface temperatures (SST), wind patterns, and decreased snowpack and snow cover have also been linked to droughts."
"Discernible human influences now extend to other aspects of climate, including ocean warming, continental-average temperatures,temperature extremes and wind patterns".
Recent research suggests " The tropical easterly trade winds are expected to weaken" [2].
Fine detail of specific local effects of climate change remains a challenging field of research, and I do not know of any research suggesting they can predict small-scale changes in wind patterns. SemanticMantis (talk) 19:49, 30 January 2017 (UTC)[reply]
I think I'd start by researching the effect of climate on the Hadley cell, which itself is subject to debate. But if the boundary of the Hadley cell moves north, then the position and intensity of the trade winds might change. How this affects a wind farm... hard to say. But maybe someone can... Wnt (talk) 23:27, 30 January 2017 (UTC)[reply]

Winds in west Texas will be tied to changes in the Great Plains low-level jet. There was an article on predicted 21st century changes to the Great Plains LLJ a few years ago. (here). Shock Brigade Harvester Boris (talk) 00:47, 31 January 2017 (UTC)[reply]

Thanks everyone! This was something I had never thought about and wanted to see what was out there - but my search skills were not up to par to find something definitive. A slightly different question... do you think that in certain areas its almost certain there will always be wind? For example, the shore? Thanks! Brusegadi (talk) 05:37, 31 January 2017 (UTC)[reply]

  • Yes, sea breeze is guaranteed to happen once (one back-and-forth) per day when a large enough body of water is close to a large enough body of land.
It does not mean, however, that a wind farm near the cost is a surefire investment. Instantaneous wind power scales as the cube of wind speed, so from a pure efficiency point of view it can be better to have strong gusts of wind now and then than a steady wind (see e.g. [3]). (BTW, I think this is the reason wind farms are often stopped when you look at them: they are designed to work for a specific range of speeds because of the weight/friction vs. mechanical resistance tradeoff, and you can sacrifice a lot of the low-speed range to extend the high-speed range because of that cubic factor.) TigraanClick here to contact me 10:36, 31 January 2017 (UTC)[reply]
Actually, the opposite is true. Often wind farms are stopped because the wind is too strong, so they've engaged their brakes. (You can find spectacular videos on YouTube of turbines whose brakes have failed on a windy day.) They do this, because as you say, power is the cube of wind speed, so making the turbines capable of withstanding those high speeds would be very expensive, and it would be a waste of resources if the local weather only occasionally reaches those speeds.
This is discussed very briefly in the Wind turbine design article, but I wish it went into it more. ApLundell (talk) 14:20, 31 January 2017 (UTC)[reply]
They used to build huge windmills to grind flour everywhere. These where huge investments back then noone had done if wind patterns would change in a way that could make these windmills obsolete. So in general wind doesnt change more then the weather. So as its also always possible that it will not rain somewhere for some time, it wont stop raining forever unless you pick a very bad spot (like at the edge of a desert). --Kharon (talk) 22:53, 31 January 2017 (UTC)[reply]

Non-dairy creamer is not sweet[edit]

Little plastic container

Why isn't non-dairy creamer when it contains lots of corn syrup. I see in some brands, corn syrup is a main ingredient or the main ingredient. Some baby formula seems to be the same: lots of sugar but not sweet. Anna Frodesiak (talk) 12:43, 30 January 2017 (UTC)[reply]

They're at least mildly sweet to me. Maybe it's cause the slow dissolving spreads out the taste over more seconds than if the non-sugar parts weren't there. Sagittarian Milky Way (talk) 13:16, 30 January 2017 (UTC)[reply]
Yes, opinions/tastes vary. I wonder what brand you are thinking of? Aren't you in China? If so, I'd suspect the regular non-dairy creamer might be a little different than what we commonly see in the states vs. AU or EU (just like we have slightly different teas and colas etc.). Also corn syrup comes in various concentrations of sugar. High fructose corn syrup has attracted a lot of criticism recently, but that's not necessarily what is in your non-dairy creamer. SemanticMantis (talk) 16:05, 30 January 2017 (UTC)[reply]

Maybe it's my taste buds (The Taste Buds would be a good name for an all-male swing band). I find coffee mate, generic brands of the same (whether here in China or elsewhere), and those teeny plastic containers not sweet at all. Maybe it's just me. Anna Frodesiak (talk) 23:09, 30 January 2017 (UTC)[reply]

The article says it can vary. Traditionally coffee was sweetened with "cream and sugar". The creamer technically duplicates the cream only, but cream e.g. whipped cream is often sweetened (technically "cream" by itself should be no sweeter than the milk it was skimmed off of!) And people like convenience, and sweet stuff. It all leads to sweetened creamer, I suppose. Wnt (talk) 23:33, 30 January 2017 (UTC)[reply]
"Sugar" is a broad category of substances with differing levels of sweetness when consumed. Plain corn syrup is mostly glucose, which (as you can see from the table in sweetness) doesn't taste as sweet as fructose or sucrose (a.k.a. "table sugar"). This might be the reason, though to be certain we'd have to see the ingredient list of the sweetener in question. (Anyway coffee isn't worth drinking if it's not black as night. ) --47.138.163.230 (talk) 10:55, 31 January 2017 (UTC)[reply]
Sugar is sometimes added to foods to counteract bitterness. I know some milk proteins are very bitter, but I can't quickly figure out exactly which proteins go into non-dairy creamers.
That might yield a clue, though. Figure out exactly what ingredients go into the creamer you're interested in, and see if any of them are known for being very bitter. If so, that would explain the presence of sugar you can barely taste. ApLundell (talk) 14:10, 31 January 2017 (UTC)[reply]
Just to clarify when you say "I see in some brands, corn syrup is a main ingredient or the main ingredient", you're referring to the products you're actually tasting, not the ingredients of other brands or ingredient lists from the same brand in other markets? Nil Einne (talk) 14:23, 31 January 2017 (UTC)[reply]
Hi Nil Einne. I'm referring to products I'm tasting. All those liquid or powder creamers/whiteners don't taste sweet to me, nor does baby formula with sugar as a main ingredient. Anna Frodesiak (talk) 20:12, 31 January 2017 (UTC)[reply]
  • Also relevent to the "De gustibus..." comment that I made above is the notion of the supertaster. To go along with the things people note above about "bitterness", is that some people have a much higher sensitivity to bitterness; so that the overall "taste profile" of something for those people can be very different than for people without such bitterness sensitivities. In other words, where such bitter notes overtake the overall taste, the impression can be less sweet. Also, since taste is a type of qualia, rather than being a quantifiable, repeatable phenomenon, there really is no way to make reliable comparisons. We can speak in trends, as to how many people in a population may or may not experience tastes, but ultimately, the sensation of taste is a personal issue, and your tastes can not necessarily be compared to another person's in such a was as to reliably associate specific tastes with specific chemical make up. In other words, you cannot rely on your own tastes to judge exactly how the entirety of humanity will also taste the same thing. --Jayron32 15:20, 31 January 2017 (UTC)[reply]
Hi Jayron32. I guess you have a pretty good point with "De gustibus..." It seems like most others find the stuff sweet. I find Marmite quite disgusting, but I imagine others find it only slightly disgusting. Anna Frodesiak (talk) 20:12, 31 January 2017 (UTC)[reply]
Oh, come off it. I doubt anybody really likes Marmite; they just pretend to as a way of pointing out how cultured they must be on account of not being American. Any product whose history involves the sentence "a scientist discovered ... could be eaten" is not actually as good as people say. :) Wnt (talk) 23:39, 31 January 2017 (UTC)[reply]
Marmite/Vegemite sounds tastier than the typical alcoholic beverage. ←Baseball Bugs What's up, Doc? carrots→ 18:45, 1 February 2017 (UTC)[reply]
I like Marmite. Had some on toast this morning. Alansplodge (talk) 01:16, 2 February 2017 (UTC)[reply]

Thank you all for the thoughtful replies. It is much appreciated. Anna Frodesiak (talk) 20:12, 31 January 2017 (UTC)[reply]