Wikipedia:Reference desk/Archives/Science/2013 November 5
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November 5
[edit]Earth's total water?
[edit]My question is does Earth's total amount of water vary? I was taught about the "rain-river-sea-evaporation-clouds-rain" cycle many years ago, and discussion of rising sea levels due to climate change seems to always focus on melting icecaps, but is more water being formed by us burning fossil fuel? Is there a net loss or gain from any geological process? Are we loosing water, or the gases that make it, from the top of the atmosphere to space? Is there some sort of dynamic equilibrium that keeps the amount of water constant, and if so what are it's feedback controls? This seems to have turned into a lot of questions, but I can't find anything in Wikipedia that addresses them. Thanks in advance, Tom duF (talk) 08:02, 5 November 2013 (UTC)
- I think the amount of water is slowly increasing, coming from passing comets and such. While, if water that is broken down to oxygen and hydrogen, the hydrogen can be lost to space, it takes a lot of energy to split water up, as it's quite stable, so this rarely happens. Thus, I think water is being added to the Earth more quickly than it's being lost. StuRat (talk) 08:20, 5 November 2013 (UTC)
- You don't need to break water down to oxygen and hydrogen to consume water. How about photosynthesis and metabolism in animals/humans which consume/produce water? bamse (talk) 09:51, 5 November 2013 (UTC)
- The Earth loses 3 kg of hydrogen per second, or 100,000 tons per year, by atmospheric escape. An estimate says over the 4.5 billion years the Earth has been around it has lost the equivalent of 0.2% of ocean volume. A similar amount is replaced from the Earth's interior to the surface, so the amount of water remains roughly constant. 88.112.41.6 (talk) 12:35, 5 November 2013 (UTC)
- Ahh, science. So much better than guessing.217.158.236.14 (talk) 13:24, 5 November 2013 (UTC)
- To address Bamse, all the water used to create sugar is converted back to water when it is metabolized. Organisms cycle but do not destroy water. Also, water is dissolved into sea-floor crust which subducts under the edges of the Pacific. This accounts for the high water content in magma associated with volcanoes such as Mount St. Helens which originates as subducted crust oushed under the NA continental plate, as opposed to low-water content magmas like found in Hawaii, which are caused by hotspots in the mantle, not the upwelling of priory subducted crust. In any case, that cycle also recirculates water, rather tha destroying it, over a longer time. Loss of hydrogen to space is the only real long-term factor. I do not know if it is balanced by space debris falling to earth. μηδείς (talk) 17:17, 5 November 2013 (UTC)
- Here's some support for the idea that Earth's water comes from comets: [1]. Note that this would have happened at a much greater rate when the Solar System was young and full of comets. StuRat (talk) 17:40, 5 November 2013 (UTC)
- Hmmm, it must be decreased by cement/concrete production. Whenever slaked lime is created, it is slaked with water (i.e. calcium carbonate is replaced by calcium hydroxide), after the carbon dioxide in the rock is first driven off with heat to become a permanent part of the atmosphere/ocean. Also, it should be increased when natural gas is burned (CH4 + 2O2 = CO2 + 2H2O). Wnt (talk) 00:14, 6 November 2013 (UTC)
- Thanks for your comments so far, very interesting about the seafloor being subducted with its dissolved water! Is water formed when all fossil fuel is burnt? Tom duF (talk) 06:47, 6 November 2013 (UTC)
- Yes, but that's part of the water cycle, although a rather extended part. StuRat (talk) 07:49, 6 November 2013 (UTC)
- Water is formed when hydrocarbon fuels (oil, natural gas, etc.) are burnt, but not when coal is burnt. --Carnildo (talk) 01:32, 7 November 2013 (UTC)
- Coal is a hydrocarbon with a bit of oxygen already added. Since it contains hydrogen, burning it DOES produce water. 124.178.58.238 (talk) 23:10, 8 November 2013 (UTC)
- Water is formed when hydrocarbon fuels (oil, natural gas, etc.) are burnt, but not when coal is burnt. --Carnildo (talk) 01:32, 7 November 2013 (UTC)
- If you are interested in the volume of water, rather than the mass, thermal expansion is important. Warmer water takes up more space. In this IPCC link (from the Wikipedia page on sea level rise), it is stated that "During recent years (1993–2003), for which the observing system is much better, thermal expansion and melting of land ice each account for about half of the observed sea level rise, although there is some uncertainty in the estimates." Jørgen (talk) 11:48, 6 November 2013 (UTC)
John Wayne on the phone
[edit]- Hellfighters (film) (1968)
I saw this while I was channel surfing. I did not see the beginning. Nor did I see the end. I don't even know if the details are correct. The movie was not science fiction.
Jim Hutton and his newly-wed wife (Wayne's daughter) was seeing a house at night with John Wayne. They wanted to buy the house immediately. Then Wayne's car phone ringed! He picked up the phone and heard about some very important thing.
What was that car phone system? -- Toytoy (talk) 09:08, 5 November 2013 (UTC)
- I can not find a clip of it, but it might have been one of the phones on these web pages here, here or here. Richard-of-Earth (talk) 09:42, 5 November 2013 (UTC)
There were indeed many car phone systems in 1968, see also our article on History of mobile phones. The Improved Mobile Telephone Service would have been the most recent system then. As an aside, Lyndon B. Johnson had two car phones as a senator in the 1950s; there's an anecdote that he was the first senator with a car phone – and when another senator got one and called Johnson's car from his own, Johnson told him, "Hold on, my other phone's ringing."--Rallette (talk) 10:10, 5 November 2013 (UTC)
- The first wireless telephone was invented roughly a century ago, and there were car phones by at least the post-WWII era. An early episode of TV's Superman series showed Perry White with a car phone. ←Baseball Bugs What's up, Doc? carrots→ 10:57, 5 November 2013 (UTC)
- Nathan Stubblefield received U.S. patent 887,357 on May 12, 1908 for his Wireless Telephone, using the voice frequency induction system, which he said would be useful for "securing telephonic communications between moving vehicles and way stations," but it was not used commercially. The Bell System offered limited car telephone service as early as 1945, per [2]. There were 17,000 car telephones in the US in 1958, and the joke about "my other car phone is ringing" was already published that year, and not attributed to Lyndon Johnson. His fans may have just appropriated the joke about a rich Texan named "Sol." . Early car phone service may have been just a 2-way radio, with an operator doing the dialing, rather than the direct dial cellular service which came along decades later. By the 1960's at least there was direct dial service in cars, with a touchpad rather than a dial, since there might be a tendency to turn the steering wheel while turning the dial. They were expensive status symbols in the early 1960's, used by business tycoons, entertainment stars and big-name politicians. Edison (talk) 15:38, 5 November 2013 (UTC)
- And if you're wondering why car phones came along decades before cell phones, it's because, at the time, the technology required made them too heavy, expensive, and power-hungry to be carried on a person. However, a car solved the weight and power issues. The expense was still a problem, though, making them only for the rich. StuRat (talk) 17:30, 5 November 2013 (UTC)
- There was a gradual transition. Maybe you remember the so-called "bag phones" of the early 1990s which were somewhat bulky and heavy. But at least they were beginning to see wide use, and each generation after that got smaller. ←Baseball Bugs What's up, Doc? carrots→ 01:15, 6 November 2013 (UTC)
What I remembered about the scene:
- John Wayne parked his 1960s pre-oil crisis American car.
- John Wayne and others were seeing a beautiful house at night.
- The car phone buzzed!
- John Wayne picked up the phone and talked right away.
When I heard the buzz sound I was confused. What in the 1960s could made that kind of noise. I wasn't even born yet. Then he picked up a very traditional-looking white handset and answered the phone call. I did not see the car phone equipment. I did not see the other end of the line (i.e. the caller). I don't know if the car phone is capable of calling out. I don't know if that car phone required an operator. I don't remember if the car has a big antenna for that phone. It was probably a movie prop anyway. They probably just put an ordinary telephone in the car. They did not need to install a very expensive car phone in the car even though it was available in the 1960s.
John Wayne played an experienced oil well firefighter in the movie. He deserved a very expensive car phone. -- Toytoy (talk) 14:24, 6 November 2013 (UTC)
- Electric buzzers are quite old, although our article lacks any history section. It's basically just like the bell on an old home phone, but lacks the actual bell, so the clanger just rapidly knocks back and forth between a couple strips of metal. (It sounds nicer with the bell, but that takes up a bit more space.) StuRat (talk) 16:29, 6 November 2013 (UTC)
- I know that buzzers were old. But I did not expect that a buzzer was installed on a car. I did not expect that a buzzer was a part of a 1960s car phone. Interestingly, the car phone did not use the "ring ring ring" noise (a DC motor + a rotating arm + a brass bell) even though it used an ordinary-looking handset. -- Toytoy (talk) 17:07, 6 November 2013 (UTC)
- I think the main reason for the bell is to make a loud ring that can be heard throughout the house. In a car, you are presumably quite close, so it doesn't need to be loud. In fact, a loud sound while driving could cause you to swerve. StuRat (talk) 18:50, 6 November 2013 (UTC)
- Earlier I referred to that Superman episode. Go to about 7:55 or 18:10 of this clip,[3] and you can see the carphone that Perry White supposedly had. Given the camera angle, I wouldn't claim it was physically in the car, but the main point is that they existed and presumably (or possibly) looked something like that. ←Baseball Bugs What's up, Doc? carrots→ 17:48, 6 November 2013 (UTC)
- 1960s British police car radios had a telephone handset [4] - they weren't called "car phones" or "mobile phones", just "radios". Alansplodge (talk) 13:34, 7 November 2013 (UTC)
Does any Anti-Histamine Nose spray exist on the market?
[edit]Thanks. Ben-Natan (talk) 11:49, 5 November 2013 (UTC)
- Yes, plenty. Google is your friend. Try searching for "Antihistamine nasal sprays".--Shantavira|feed me 12:01, 5 November 2013 (UTC)
- Yes, but only two in the US, according to Nasal_spray#Antihistamine_nasal_sprays: "Astelin (azelastin hydrocholoride) and Patanase (olopatadine hydrochloride) are the only antihistamines available as a nasal spray in the United States and are available by prescription only. In Australia Telnase (Triamcinolone acetonide) and livostin (Levocabastine hydrochloride) are the most popular products currently on the market and are available over-the-counter." OsmanRF34 (talk) 21:21, 5 November 2013 (UTC)
- Triamcinolone is a steroid anti-inflammatory, not an antihistamine. --Trovatore (talk) 21:59, 5 November 2013 (UTC)
- If you are right, and it seems you are, but I don't have a source, then the article should be corrected. OsmanRF34 (talk) 23:49, 5 November 2013 (UTC)
- I have commented out the offending passage, which is unreferenced anyway. There is probably nothing wrong with the content, it's only the placement that is confusing. --Trovatore (talk) 00:49, 8 November 2013 (UTC)
- If you are right, and it seems you are, but I don't have a source, then the article should be corrected. OsmanRF34 (talk) 23:49, 5 November 2013 (UTC)
- Triamcinolone is a steroid anti-inflammatory, not an antihistamine. --Trovatore (talk) 21:59, 5 November 2013 (UTC)
- If you need advice on such sprays speak to a doctor, or pharmacist. Medical disclaimer applies.Sfan00 IMG (talk) 12:10, 8 November 2013 (UTC)