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I've noticed that LED bulb packages say they'll last several years, but so many of them die after just a year or so. I should start tracking this precisely, but I've just gotten the sense that they often die prematurely.


You have 2 year warranty. Return it. My dad did it so often that they refuse to sell him a new one in that shop. What an irony.


Why? That strikes me as odd, since the manufacturer is the one who eats that warranty cost.


Assuming that the retailer can actually get a refund or replacement from the manufacturer (for some products, only the consumer can actually do that), usually they just replace the item or the wholesale price. They don't replace the retailer's gross margin. Thus the retailer ends up eating the cost of things like stocking and actually processing the warranty. For e.g. a one-person operation, that means extra work for zero profit.

It's usually not that much, but I can see why they might eventually be upset about it.


I got that impression too, but it does say "But the path he has chosen involves one of the toughest problems in battery science, which is how to make an anode out of pure lithium or sodium metal."

I suppose that implies he's trying to make an anode out of pure lithium or sodium, but you never know with science journalism.


"When the battery is discharging ... positively charged ions shuttle from the anode to the cathode"

I thought that electrons shuttle from the anode to the cathode.


Inside the battery positive ions move to equalize charge. Outside the battery, electrons cause a current in conductors.


I never understood the animus against saving. Saving just means you have produced more than you consumed, and I admire that.


Are there any data on water vapor concentrations? I ask that because I have read that the contribution of water vapor to the greenhouse effect is perhaps two to four times greater than CO2.


Water vapor is a much larger contributor to the greenhouse effect than CO2. There is a lot more of it in the atmosphere.

The reason water vapor cannot be a forcing (i.e. root cause) of global warming is because of how short the water cycle is. If the amount of water vapor in the atmosphere increases, it is rather quickly balanced back by fixing some of the water vapor into liquid water. We call this process "precipitation."

I've seen estimates that the length of the water cycle is on the order of a week or two. So if human activity puts a lot of extra water vapor into the air--say, with a nuclear power cooling tower--then the excess water vapor will precipitate back into the liquid water within a week or two.

Human society has adapted very well to this cycle. We have built our societies to manage rain and snow [1].

The carbon cycle is much longer--I've seen estimates on the order of several decades at least. Thus, if human activity puts an excess of CO2 into the atmosphere, that will be there for several decades or longer. Thus the effect has quite a bit longer to compound, producing changes that seem long-term to human societies.

We have not built our societies to adapt to the effects of these types of trends. Think of how many human structures within just a few meters elevation above mean sea level, for example. Like: most of Manhattan.

Water vapor is a feedback. If the average atmospheric temperature goes up (for any reason), it can hold more water vapor, which then further increases the greenhouse effect, which raises the temperature more, etc. One reason scientists build complex computer models is to figure out how a little bump in temperature (from CO2 for example) can be magnified by feedbacks like water vapor.

[1] Well, at least in the volumes that have been common over the past few hundred years.


Not only that, all greenhouse models require a 'water feedback loop'.

Of course there are plenty of anthropogenic water emissions to go about. When you irrigate, you are effectively throwing water into the air - by increasing the surface area of water evaporation through plant transpiration networks.

I have never seen anyone talk about this alternative hypothesis.

A disclaimer - I am all for reducing CO2 emissions strictly on principle (this is not dependent on the effects of CO2) and have put my money behind my beliefs - I have driven hybrid vehicles to support technology towards that end since 2003. But in my judgement as a scientist in general (and to some degree as a chemist who has done advanced spectroscopy including IR spectroscopy) I am losing confidence in climatology.


It's a reasonable question. While I am not a climatologist...

Anthropogenic evaporation is probably minuscule next to deviations in natural evaporation due to small changes in temperature. A single hurricane, for example, dumps more power (as heat) than all human power generation.

Also, unlike CO2, I would also guess that atmospheric water probably reaches equilibrium much faster (half life ~1 year instead of ~30 years).


There is basically no equilibrium condition here. If you mean that there is a more 'inelastic' equilibrium constant, then keep in mind that the concentration level governed by such a constant is dependent on rate in versus rate out, and there are certainly ongoing inputs of ag water. We've completely drained several seas and underground aquifers as a result of human activity in the last 50 years.


The amount of water used globally (approx 10^13 m^3) is only about 2.5% the total yearly evaporation off of the ocean (approx 4*10^14 m^3).

I suspect small changes in climate have a much greater effect on net evaporation.


I'm pretty sure your concerns have been addressed. Is it reasonable to 'lose confidence' because you haven't read the research?


pray tell, enumerate my concerns and show me how they've been addressed. Is it reasonable to assume they've been addressed just 'because scientists'?


does 2.5.6 from http://www.ipcc.ch/pdf/assessment-report/ar4/wg1/ar4-wg1-cha... address this adequately?

(I was curious from your comment, but only spent a minute looking)


Read the section yourself and ask if it does. They say right there that they don't do the calculations because it's too uncertain.


Ah, but that's not at all the same as not addressing it, or as you state "I have never seen anyone talk about this alternative hypothesis." (of course I read it, and asked that question)

They are talking about it, and saying that it's a potential source of error that nobody knows how to account for yet, which is pretty common in science. If someone can demonstrate that the potential effect is dominant, it's a real problem. If someone can demonstrate that the potential effect is trivial it can safely be left alone. Otherwise you do the best modeling you can with the best data you can and talk about the possible confounding issues as so we proceed.

So I don't see any particularly damning issue here, have I missed something? It would be nice to resolve the differences between estimates. Is i the lack of analysis of radiative forcing that is bothering you? Do we have any reason to believe it can be a significant term? These sources of vapor are certainly not large (relative to total sources of water vapor in the atmosphere) so I'm not seeing the mechanism.

This really isn't my area, and as always I'm more than happy to be wrong (I learn more that way).


A lot of this is answered in the IPCC reports, which have readable, short summaries:

https://news.ycombinator.com/item?id=9772353


I searched on the words "vapor" and "vapour" and found nothing. I also search on the word "water" and found nothing relevant to my question.


Perhaps the searches are [EDIT: not] looking in the PDFs? I just opened the Summary for Policymakers for the Physical Science Basis report, and found a few discussions of water vapor in the atmosphere.

I'd try looking at "Physical Science Basis" and "Impacts, Adaptation and Vulnerability" reports; try the Summaries for Policymakers first, and the full reports if those don't have what you need (though go straight to the full reports if you have time -- they can be fascinating!).

I hope that helps.


I opened the "Summary for Policymakers" listed right on their home page, and it popped up a PDF titled "AR5_SYR_FINAL_SPM-1.pdf". That's where I searched on the word "vapor" and found only one occurrence -- inside the word "evaporation".

I guess the "for the Physical Science Basis" report is something different that I haven't found yet.


Holy cow do they make it hard. I had JavaScript off, which made their page much more usable. Either do that or ...

With JavaScript on, apparantly the UX concept is 'Easter eggs': There are 4 images arranged horizontally at the top. If you click image, one the section beneath it changes. The second image is "Physical Science Basis".

All that work making the reports accessible, hamstrung by web design.


Read the entire executive summary. Micro-questions aren't meaningful if you don't have at least that level of understanding.


Likely yes, but please be careful that the remedies do not cause more severe difficulties than the problem itself.


Implicit in this remark is the idea that all humans share roughly the same interests and concerns. As difficult conditions exacerbate conflicts the weight of interests is measured first in capital and then in violent prowess. http://www.ft.com/cms/s/0/bc2016e2-d320-11e4-9b0a-00144feab7...


Sorry, I can't click through to that article -- when I dismiss the pop-up, the tantalizing "Climate Shock" headline disappears.

I do say that all humans require energy to survive, and more efficient forms of energy require capital in the hands of innovators.

I'll be happy to read the article if you can give me a link that functions better for me.


I found another review of the book that mentions geoengineering.

"There will still be ocean acidification, smog, ozone depletion and so on and once we set on geoengineering our planet, we’ll likely get hooked and never turn back. In many ways, geoengineering is even more uncertain in its consequences than climate change itself. Definitely far from being a solution, and even the foremost experts on geoengineering agree that it shouldn’t be done – only in extreme conditions, like when there isn’t any other choice." http://www.zmescience.com/other/reviews/book-review-climate-...


Sorry I deleted my comment out from under your feet. He was responding to my exclamation about the large spike upward in CO2 levels on that first graph on the EPA site. After posting it, I deleted it because I answered my own question.


http://www.ncdc.noaa.gov/paleo/globalwarming/temperature-cha...

There you can see a strong correlation between CO2 levels and temperature going back nearly half a million years. Teasing out cause and effect is the interesting task.


yeah, that correlation is totally the wrong way; the blue curve leads the red curve. Now, Look at the key:

Temperature change (blue) and carbon dioxide change (red)


Yes I understand that effect, and it makes sense that higher temperatures might cause more CO2 to come out of solution, as in a bottle of soda going flat more quickly at room temperature than in the refrigerator.

That said, I am not certain that the recent dramatic spike to 400 ppm of CO2 (from what I've read) could be entirely caused by the fairly moderate temperature rises measured in recent years.


In Lima Peru the bus drivers pay spotters on the street who report flow conditions by cell phone.


They do this in my city too (Bogotá, Colombia). It's actually illegal here, but they do it anyway.


It's bizarre that it would be illegal. For all I know, it might be illegal in Peru too, but it happens, and it works pretty well.

In Lima, the spotters are known as "dateros" (loosely, "data wrangler"). The bus drivers pay them roughly 20 centavos, I think per stop but I'm not certain.

One case where it doesn't work is when certain bus drivers ignore the system and aggressively jump ahead of other buses. Nevertheless, it's pretty smooth.


Some have already closed that exit, banning the storage of cash in their boxes. They want to keep your funds available for negative interest rates and possible bail-ins.


I think the difficulty would be finding enough safe deposit boxes. If I had $100M (let me dream, will you!) where could I store that physically? That much cash takes up a lot of space.

The Oatmeal had a post where he talked about how heavy his $200,000 withdrawal was (that was in 20's).

A little Google searching found: http://www.cockeyed.com/inside/million/million_dollars.html

I think Adam Curry talked about buying actual gold bullion and storing that. Still takes a lot of space and a lot of cost in storage. $100M in gold is over 80,000 oz. Two tons of gold?

https://en.wikipedia.org/wiki/Gold_bar#Standard_bar_weights http://demonocracy.info/infographics/world/gold/gold.html

Me, personally, if I had $100M, I'd buy an island somewhere close to an internet backbone. Real estate is always a good investment!


Yes, you're talking about 4.7 cubic feet of gold there. Buy the island and then you'll have a place to store 1 cubic foot of gold, to pay your routine expenses.


Could you just put the cash in a cardboard box and then say it's important papers or stock certificates? Do they have the right to open it?


Of course they do. If they lie and say it smells like marijuana.


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