Global warming

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Sorry, but you're not going to get a headache from the light receptors in your eyes receiving, on average, ever so slightly different amplitudes of various frequencies.
Agreed. The Philips LEDs even specify and allow you to choose the spectrum and illuminance profile you like best. You can do that very well with LEDs.
 
Strangely enough, that only works if you seldom turn them off and they're decently build (again, Osram and Philips).

The cheap ones don't last that long, and if you use them in the toilet, where they're turned on and off very often, they tend to last a lot shorter than your regular light bulb.
I'll grant you on the cheap ones. There have been spates of rather poor-quality fluorescents out there. But by far the majority of lamps in a home are left on for much longer than a few minutes. I also doubt your numbers. The closest I could find is that if you turn on/off a compact fluorescent in five minute cycles, its lifetime becomes close to that of an incandescent (at which point the cost savings from electricity becomes close to on par with the extra cost of the bulb).

Edit: It looks like the "rapid cycle test" for CFL's involves ensuring that the CFL's last half their rated time on a five minute turn on/off cycle, indicating the savings are still going to be significant:
http://spectrum.ieee.org/green-tech...rescent-lightbulbs-really-cheaper-over-time/0

Edit 2:
Oh, and this too from the article:
Playing with the default assumptions given in the sheet, we reduced the CFL’s lifetime by 60 percent to account for frequent switching, doubled the initial price to make up for dead bulbs, deleted the assumed labor costs for changing bulbs, and increased the CFL’s wattage to give us a bit more light. The compact fluorescent won. We invite you to try the same, with your own lighting and energy costs, and let us know your results.
 
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I read about the distribution of light energy spectrum, which is said to be "spikey" on CFLs and since we are accustomed to a smooth distiribution of inascendent light sources, it can cause issues.
For me CFLs are unpleasant, I admit that I haven't tried LEDs really.


edit:
I also read that riding a bike can cause more CO2 pollution than a car since you need to eat more. Those electrically assisted bikes may be different. :)
 
Chalnoth said:
Playing with the default assumptions given in the sheet, we reduced the CFL’s lifetime by 60 percent to account for frequent switching, doubled the initial price to make up for dead bulbs, deleted the assumed labor costs for changing bulbs, and increased the CFL’s wattage to give us a bit more light. The compact fluorescent won. We invite you to try the same, with your own lighting and energy costs, and let us know your results.

Well, I did try it out for more than five years. :) Ok, anecdotal evidence.

In my experience, the cheap fluorescents in the toilet and bathroom broke down after about half a year on average. With a family, that number should be lower, as the cycle rate increases. The good ones did better, but not spectacularly so.

And the current, old style light bulbs have survived for a few years by now. I'm happy I still have some stacked. :)

If I run out, I'll replace them with LED bulbs.
 
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I also read that riding a bike can cause more CO2 pollution than a car since you need to eat more. Those electrically assisted bikes may be different. :)

I remember such as study but it was an insane troll, assuming you will only be eating more steak. deriving your energy input from protein is wasteful and unhealthy.
What about bread, potato, rice :). I like eating cheese, which is very energy intensive, but maintaining a high bread/cheese ratio.
 
Actually, the GHG emissions from food in general are pretty negligible. While there has been much said about the GHG emissions from eating meat, the fact of the matter is that any methane emitted won't matter in ten years. CO2 is, by far, the more important concern, because it lasts for hundreds of years, not just a few.
 
Actually I think here in NZ they were getting phased out by the last government, though the current government came in & stopped that PC nonsense :) like the PC nonsense of banning the sale of junkfood in school tuckshops.
Yes the government was caught up with the anti-PC hysteria from a few years ago, when any idea no matter how logical it was wouldnt see the light of day if it had a hint of PCness to it.

Im not sure if anyone here would understand that PC in this context is not personal computer. :mrgreen:
 
Methane emissions due to meat are dwarfed by other factors I believe, such as refrigeration and south american deforestation (to make room for the soja cultures which will feed cattle).

I wish our urban food wastes could fed pigs, chicken etc. as is done in third world countries or was done in the past.
I had organic waste piling up in a cardboard.. but who can I give it to? I can bring my garbage to a squat where they have a compost heap but they have quite enough.

We're not nearly recycling enough, that's become evident to me after reading articles on the Zabbaleen in Cairo. well maybe I'd love to have a pig, an ass, hen, dogs etc. :p
 
Methane emissions due to meat are dwarfed by other factors I believe,
Hmm, I would like to see support for this. So far, the only significant impact I've seen from meat in terms of AGW has been its methane emissions. You might be right, maybe the refrigeration and land use issues are also significant. Certainly there are other environmental concerns (factory farms are horrible polluters). But it was my understanding that it was the methane impact that was the primary impact from meat.
 
I'm too quick to write it off, sure. It depends on how wide you make the picture when adding up factors.

That land use is such a major global contributor is very telling - biosphere needs more respect.
 
Fertilizer for animal feed is CO2 intensive (ammonia is typically produced from natural gas). Harvesting requires machinery. There is the processing, packaging and transport of the meat itself.

Whether the CO2 does more harm than the methane, I don't know. Some of the more recent papers on methane wrt AGW points out that methane's role as a way of adding water vapour to the stratosphere is more important than it's role as a greenhouse gas.

Cheers
 
Whether the CO2 does more harm than the methane, I don't know. Some of the more recent papers on methane wrt AGW points out that methane's role as a way of adding water vapour to the stratosphere is more important than it's role as a greenhouse gas.
In any event, the reason why methane is irrelevant is the fact that methane doesn't last very long. Methane emitted today will have undergone reactions and be gone ten years from now. So even if there are secondary effects of methane emissions, they aren't going to make anywhere close to the impact of CO2, because CO2 emissions linger for hundreds of years (meaning it is the total amount of CO2 emitted that is of relevance, not just the CO2 emitted in the last few years, as it is for methane).

It's also somewhat telling that global methane levels have leveled off.

Anyway, it may potentially be correct that the CO2 emissions from meat production are more significant than I had thought.
 
Ugh. Talk about moronic bullshit.

Here's a tip: when you see wild claims, such as AGW being disproved in the 90's, you should look at the source for that claim. When no source is presented (as in this case), you'd be safe to throw it out in its entirety.

Instead, if you pay attention to the actual science, it has only fallen more solidly on the side of human-caused warming since the 90's, with CO2 being the most significant culprit.
 
Ugh. Talk about moronic bullshit.

Here's a tip: when you see wild claims, such as AGW being disproved in the 90's, you should look at the source for that claim. When no source is presented (as in this case), you'd be safe to throw it out in its entirety.

Instead, if you pay attention to the actual science, it has only fallen more solidly on the side of human-caused warming since the 90's, with CO2 being the most significant culprit.

That's not much of a counterargument. The real question is whether or not we include 2x more warming due to moist air or not. If yes, then there's cause for doubting our models.
 
That's not much of a counterargument. The real question is whether or not we include 2x more warming due to moist air or not. If yes, then there's cause for doubting our models.
Of course we do, but that's basic science. Look at a psychrometric chart. For a given relative humidity level, the atmosphere holds more water. Note that this also means you need more moisture in the air to reach 100%+ humidity (i.e. saturation and supersaturation, which is what makes clouds and rain).

What is a bit harder to predict is chaotic stuff, like a local pocket of air getting humid from the ocean, then rising due to it convection, then cooling and raining. 50% humidity at 25C will saturate if cooled to 14C (dew point), while 50% humidity at 30C will saturate if cooled to 18.5C. How this affects the atmosphere is not clear.

Evans makes himself look pretty foolish in that article. First he complains about land based thermometers, and says we should look at satellite temperatures. However, the difference is very small. Then he talks about warming since 1680, where he not only ignores magnitude and rate of warming, but also implicitly relies on temperature proxies that are even more prone to external influence than the surface thermometers he objects to. He blames the AGW movement for being selective about data, but he restricts himself to looking only at satellite temperature after 2001. I think it's pretty dumb to make that conclusion from the data (FYI this is a skeptic site). He says that nature must dampen the warming effect of CO2 (and other systems) or else it would be unstable, which clearly shows he doesn't even understand basic feedback systems. Basically, he's just full of shit.

If you really want to make a case against drastic action, just use the IPCC's own figures. If you want to save the world, money/resources spent on sustainable development is 10-100x more effective in saving human life, the planet, etc than non-nuclear renewable energy.
 
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That's not much of a counterargument. The real question is whether or not we include 2x more warming due to moist air or not. If yes, then there's cause for doubting our models.

One rather striking feature of the article you linked to is the lack of sources for its claims; it keeps talking on and on about "climate scientists" without mentioning the name of any person or any organization or any climate model - it's all nonspecific "they", "they", "they" and the occasional "the alarmists", which makes it hard to take seriously. Which data sets are disagreeing with which models and whose climate predictions? The article doesn't tell. Which pretty much blocks any meaningful discussion. Which, I guess, is the point.

Given that - and the way the article mostly reads like a standard list of climate "skeptic" arguments - and that it is written by someone with an apparent political agenda (seriously: at the bottom of the article, it says "The comments above were made to the Anti-Carbon-Tax Rally in Perth, Australia, on March 23.") I can very much see why Chalnoth would dismiss it as "moronic bullshit".
 
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