swansont

We've already got an open thread on this. http://www.scienceforums.net/forum/showthread.php?t=29963 Posts 1 & 2 have been copied over.

It's the earth as a clock that you shouldn't trust.

The mean sulfate level around 1880 is about 25. The mean suflate level by 1910 is about 75. By 1930 it's dropped to about 50. Those are the numbers from YOUR SOURCES for Pinatubo and Tambora. The effects we're looking at for 1880-1910 are an order of a magnitude smaller, so it requires volcanoes of much smaller effect to see that kind of cooling. Argument from incredulity. I've given a graph of sulphate measurements which, at least for the 19th century, should be due to natural sources.

Inertia is a Newtonian concept and isn't well-defined in quantum and relativistic applications. (at least I've never seen it defined)

That claim is not supported by your link. There is nothing in there that suggests that several small volcanoes cannot affect climate. It's not this is a binary state of affecting or not affecting, it's a matter of degree — how much and what type of material, and how much of an effect it has. Regarding Pinatubo, it says "The data collected after these eruptions show that mean world temperatures decreased by about 1 degree Centigrade over the subsequent two years." 1 ºC for two years. Tambora was cited as being 3 ºC in another link of yours. But the effect we are discussing is an order of magnitude smaller. So, again, why can't increased overall volcanic activity cause cooling? http://www.igac.noaa.gov/newsletter/highlights/1998/pascnl.php Also linked to in post #155, and prior to that.

This does not follow. A valid conclusion might be "do not assume global cooling of more than 2 years from a single volcanic event." But I have not claimed that the cooling in question comes from a single event. ——— I asked you to address the sulfate graph — it clearly shows a marked increase when there is cooling. I also asked what evidence supports your claim about the warming; you've admitted that the cooling after 1940 was not sunspot-driven, now I ask you to look at the rest of the graph.

Here's an example of where quantifying things, as I've previously requested, would be quite useful. We'd avoid the false dilemma presented here (and the distraction of discussing CO2 concentration when we really want to look at the temperature effect of the change in concentration). "Trivial" means of little value, i.e. very close to zero, and can be ignored. I take that to mean very small compared to other terms . The overall temperature change being 0.4-0.5 ºC, 0.175 ºC is not trivial. Now, what's "major?" Let's use your exact quote, "Swansont claimed that CO2 increase was a major, if not THE major cause of warming from 1910 to 1940." THE major cause should be the biggest one. Is it too difficult to see that something can be a) not trivially small and b) not the biggest at the same time? Wait. Let me get this straight (ignoring, for the moment the "12 month claim"). A singe big volcano will drop temperatures, and several smaller volcanoes, do add up to the effect of one big volcano, BUT you can't have this happening continually for many years in a row. Why? And regardless of the source, why couldn't the tripling of sulfates cause the cooling in question, and the subsequent reduction in sulfates cause some/much of the later warming? TO WHAT GRAPH ARE YOU REFERRING? (Why is this such a difficult piece of information to include?) Certainly not the one from Solanki's 2007 paper that I posted earlier, which clearly shows ~ 0.01 fluctuation in TSI from ~1885 - 1930, as compared to the ~0.06 change from 1930 - 1955 ——— What is the experimental basis of your claim that solar is responsible for 0.4 ºC of warming between 1910 and 1940? (Keeping in mind that Solanki's 2004 paper has been superceded by the 2007 paper) Can you point me to all of the citations you made in the last post directed at me, pointing out how the TSI data support you? http://www.scienceforums.net/forum/showpost.php?p=382291&postcount=157 ————————— To address something I skipped over before. The link you proveded does not actually say this. It says (regarding Tambora) "Even a year after the eruption, most of the northern hemisphere experienced sharply cooler temperatures during the summer months." That is not the same as saying that no cooling was present after 12 months, just that it was not as large, i.e not sharply cooler. You cannot draw the conclusion that the effects are limited to a year from this statement. It also says "An eruption the size of Mount Pinatubo could affect the weather for a few years." By what mechanism does it affect weather, but not be abe to affect temperature?

Add to this the fact that it takes time to find citations and direct quotes, so coming up with proper responses takes longer than a post that has poor or nonexistent supporting evidence.

[math]A=\pi r^2[/math] is the formula for area of a circle. You used S rather than A, which is more commonly used. Not really a big deal.

Neat summary that was just emailed to me. Drop a marble onto a bed of fine sand and you get a fluid-like response, but there's no cohesion or surface tension as in a fluid. Also, you get jets of sand from the interactions in the impact void whose behavior depends on the ambient pressure. http://jfi.uchicago.edu/~jaeger/group/granular2/jets.html

I'd say it as: your odds of dying don't noticably increase with height after a certain point. Not that they can increase much ...

What's the level of "permanence of memory" of a three-year-old? i.e. how unusual is it not to remember such stuff at that age? I have no persistent, clear memories of before I was ~ age 6. Anyway, the November 2007 issue of "National Geographic" has an interesting article (nontechnical) on memory. http://ngm.nationalgeographic.com/ngm/2007-11/memory/foer-text.html

The "get new posts in the last 6/12 hours" options seem to have vanished. The Spy feature doesn't seem to take their place under all circumstances.

You'll hit terminal speed, of ~120 mph (depending on your mass and surface area) at some point. Since drag depends on speed squared, your acceleration will rapidly diminish, so 90 stories would give you about the same speed as 47. There my be some stats out there from accidental falls and suicide attempts that would tell you the probability of surviving a jump or fall from a certain height, and it should flatten out at some point, at slightly above zero. (A few people have survived parachute-less jumps from planes.). I have a vague recollection of such information; there's a threshold where you get injuries and few deaths, and then transition into mostly deaths. But I can't find anything relevant at the moment.

Depends how loudly you yell. The thing is, that perceived sound needs to increase by a factor of 10 to sound twice as loud, because our perception is nonlinear. Shouting might only represent a small fraction of a watt. So let's do a back-of-the-envelope calculation: 8 years for a 250 mL cup raised 60 ºC requires about 60 microwatts continuously over that span (assuming 100% efficiency and ignoring the heat loss from the cup), which corresponds to 77-78 dB and that's louder than normal conversation volume. http://en.wikipedia.org/wiki/Sound_power Order-of-magnitude-wise, the statement seems OK. Certainly not egregiously wrong (assuming no calculator errors) edit: Oops. forgot a conversion — I was using calories instead of Joules. You need ~240 microWatts. That's 83-84 dB

The acoustic power of very loud music is in the tens of watts. 90 dB, which is pretty loud, is about 20 Watts. The power to most speakers runs along some pretty wimpy wire, which should give you an indication that they don't draw much current and therefore don't convert much electrical into acoustic energy.

You appear to be predicting states that have not been observed. When an electron changes between these states, how does the energy difference occur? Does the system absorb or release photons? Have these been observed?

No, I didn't. This is a strawman. I have been rebutting your claim that "The biggest increase in sunspot activity, which drove a 0.4 C warming at a time when greenhouse gas increase was trivial, occurred from 1910 to 1940." I did a calculation (using the data and boundary conditions supplied by you) that the CO2 increase from 1870 to 1940 should be responsible for a ~ 0.175 ºC increase in temperature over that time frame. This is not trivial. What I've said is that a change in volcanic activity and the change in CO2 by themselves combine to account for more than half of the temperature change in that time frame. Solar cannot and does not account for that trend. You have not substantiated that claim (the one study you cited that supported it has been revised by its authors, such that it no longer supports your claim.) IIRC 1883 was Krakatoa, and in 1902 there were three major eruptions. And lots more smaller ones. You don't need a major eruption in a year if you have many smaller ones. If you had indeed looked at the link I provided http://www.igac.noaa.gov/newsletter/highlights/1998/pascnl.php you'd have seen that average sulfate levels (as measured in Greenland) tripled between 1880 and ~1910 or so, and then dropped significantly. So if you get increased cooling from the elevated sulfate levels, you should then get warming when they drop. The drop in sunspot activity (from the TSI reconstruction of Solanki I cited) started ~10 years earlier than the temperature drop, and only lasted ~15 years — after that it was pretty flat until 1930. (Oh, and before you cited ~0.2 ppm per year. Now it's 0.1 ppm per year? I get 0.185 ppm per year from the numbers you provided)

You should get interference of the overlapping beams. Toplogically this is no different than two sources placed side-by-side. As long as they are sufficiently coherent, you should see interference.

Yeah, and I should have kept reading, too "yield strength of annealed material is approximately one-third the tensile strength." and "Yield strength of a hard-temper copper is approximately two-thirds of tensile strength." And obviously a monolayer of copper won't withstand the same pressure as a micron, which can't withstand the same pressure as a millimeter, etc.

AFAIK it depends on the copper properties (e.g. composition, whether it's been annealed) or if it's a copper alloy. http://www.roymech.co.uk/Useful_Tables/Matter/Copper_Alloys.html "Copper alloys do not have a sharply defined yield point" that's the point where you transition from elastic to plastic deformation. They also list tensile strength as being between 200 and 400 MPa, so that's probably your pressure range. What's the application? "capped at both ends" makes it sound like a pipe bomb.

IIRC it's an effect from the orbit that gives rise to the "equation of time" (represented by the analemma — that squashed figure-8 you see on a globe or map). We just had the perihelion, which does not match up with the solstice, and that skews the sunrise/sunset symmetry.

We send a van to do remote satellite calibrations elsewhere in the US, which then returns and you check the local linkup to "close the loop" and make sure no errors have been introduced. I was reading a trip report and noticed that the accumulated kinematic time dilation from driving at <70 mph for a cross-country trip & return was of order 1 - 2 ns, and you can measure that with the clocks compared to the main ensemble that comprises the "master clock." People often say that the effects of relativity are only noticed when you go close to the speed of light, but it's also the case that they are noticed when you have very good clocks. We're almost to the point where putting the clock on the second floor vs the first floor will give a measurable difference in performance, and another step away from when solid-earth tides, which are ~half a meter, will become noticable (gravitational dilation is a part in 10^16 per meter) Since the surface is rotating it's accelerating and thus not inertial. You have to use an observer, e.g. sitting above the north pole (which is what is used in the paper) in order to do the analysis. You can (and people do) use an earth-centered inertial (ECI) frame, but that introduces extra terms, much like a rotating coordinate system has pseudoforces to make thing behave in a Newtonian fashion. In the ECI you have the Sagnac effect, which introduces a time difference for travel parallel to the equator. Something like 207 ns is introduced for a complete circumnavigation in the ECI frame.

Yeah, seeing her doubled over in laughter like that is something I won't soon forget. 'Twas a stroke of genius.

Entanglement doesn't work that way. You don't know the spins, so you can't say that one of them changes its spin; all you know is that when you measure one that the other will have the complementary value.