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Comment: Re:There's only three plants. (Score 1) 417

by AdamHaun (#49322601) Attached to: How 'Virtual Water' Can Help Ease California's Drought

I was talking about the suggestion that California uses enough water to have a significant effect on Pacific sea levels. My back of the envelope estimate suggests that lowering the Pacific by one inch would take at least ten thousand times as much water as California uses in a year.

Comment: Think of it as evolution in action... (Score 2) 335

... not of us, but of them. ISIS is sort of like an extremely virulent infection. It is really bad if you get it, but it kills so fast that the patient dies before the infection has time to spread much, and it has EVERYBODY working to exterminate it. At the moment, all of the batshit crazy teenagers filled with Islamic Angst are heading ISIS-ward to be indoctrinated and (one supposes) employed eventually as suicide bombers. The only problem is, it requires a special kind of crazy to become a suicide bomber or fatwah-murderer, and the world has a finite supply of that kind of crazy. The other problem is that collecting all of the nut-cases in one place makes it comparatively easy to (eventually) hit them with the moral equivalent of an antibiotic.

The only thing that I can see ISIS accomplishing is -- eventually -- convincing the moderate Islamic world that it is better to be an atheist (or at worst, any other religionist) than to be Muslim. Pakistan made a major play in that direction yesterday when the woman was beaten and then burned to death for allegedly burning the Quran. It publicly stated that it was wrong for the public to have killed this woman for burning the Quran -- only it (the government) got to prosecute and then murder the woman for burning the Quran. It never occurred to them that it might be absolutely insane to murder somebody, ever, for burning a book that you bought, paid for, and own. Especially a violent, psychotic, hate-filled document like the Quran. Or a violent, psychotic, hate-filled document like the Bible (either part). Or any religious text, violent, psychotic, and hate-filled or not. Or a copy of Dirac's Quantum Mechanics (although there it might arguably be an act of criminal stupidity).

I'm tempted to go out and burn a Quran myself out of sheer sympathy and in protest and in support of freedom of speech and freedom of (and from!) religion. But first I'd have to buy a copy of the Quran, and who wants to reward the idiots who publish it? So I just bring up copies of the Skeptics Annotated Quran on my browser and then -- wait for it -- close the browser window. Just like that, I make my current copy of the Quran disappear, even worse than just burning it. Over and over again. I may even write a script to copy an online version of it and overwrite it repeatedly with random numbers. Some people are so very, very, 17th century clueless about information.

rgb

Comment: Re:Claims should be easily verified (Score 1) 573

by rgbatduke (#49312997) Attached to: Greenpeace Co-Founder Declares Himself a Climate Change Skeptic

The really fun thing is that an entire ice age occurred with CO_2 never lower than around 4000 ppm. Sure, it was a long time ago, completely different land mass arrangement and so on, but still something that IMO completely eliminates the "Venus catastrophe" possibility Hansen has warbled about with boiling seas and so on triggered by CO_2 around 1000 ppm. I doubt many (other) climate scientists take it that seriously either, but hey, criticizing another climate scientist about an egregious climate claim publicly, especially Hansen, for speaking nonsense in public is like a priest criticizing the pope these days in more way than one. Hence you will learn privately that many climate scientists have some doubts about whether or not catastrophe is inevitable, or whether ECS is really 3+ C instead of, say, 1.4 C, but they tend to be very careful about stating it on national television or even to a reporter. There is never any shortage, however, of people calling for more violent storms or reporting on the horrors that await us (according to an incredibly implausible calculation or study) when climate does what the high ECS models claim that it will, sometimes (in some PPE runs).

A very recent paper -- very very recent -- has done a careful study of the integrated effects of aerosols on the climate (aerosols cool, and current models achieve high CO_2 gain by taking pure radiative CO_2 trapping of around 1 C and augmenting it with 2-3 times more from water vapor feedback, subtract a large and uncertain part of that against aerosol cooling, and then show runaway warming when CO_2 increases outpace aerosols). It lowered the upper bound of the aerosol coolng from around -2 C to -1 C, and dropped the lower bound to -0.3 C, with a most probable value around -0.5 C.

If correct and verified -- and the work appears to have been very carefully done, but who knows, we will see -- this result will reject most of the models in CMIP5 which get their high ECS and TCR from the large cancellation. Fitting a function by cancelling two large terms is numerically a much riskier and less precise an operation because small relative errors in either function make big relative changes in the result, and this generally applies to things like climate models that actually are solving a computational fluid dynamics problem. The models themselves can probably be rebalanced to fit the reference period with a much lower aerosol, but this will without question require them to readjust the water vapor contribution radically downward since there is no aerosol cooling to speak of to trade it off against in the reference period. This in turn drops ECS -- by roughly a factor of 2.

Lewis and Curry reran a climate model with the new numbers and got an ECS distribution from 1 to 2, centered around 1.45 C, which is very close to no net feedback on top of pure CO_2-only warming. I get numbers in the same range when I fit atmospheric CO_2 (inferred from e.g. ice core data and smoothed to fit the industrial increases from 1850 to the present) to HadCRUT4 -- a direct fit of the global anomaly (for what it is worth) yields ECS around 1.8, well within their error estimate, and a two parameter fit of logarithmic warming has sufficient explanatory power of the data that there is little left to explain -- a weak 67 year sinusoid with amplitude around 0.1, that's it. But that is only 164 years of data, and the error bars on the first 2/3 of that data are large enough (and never shown to the public) that grown statisticians weep when they see the certainty of all claims about the climate and the abuse of fitting non-stationary timeseries.

It will be very interesting to see what impact this has on the public discourse -- in six months to a year. ECS was in freefall anyway -- the "pause" in global warming and increasing divergence of the model predictions from the actual temperature have been weakening confidence in the unproven assertion that one can take a collection of disparate CFD codes, apply them with wildly different parameters at spatiotemporal length scales 10^30 times larger than the Kolmogorov scale for the problem, form the envelope of the resulting chaotic trajectories from nearly arbitrary initial conditions (since we have no idea what the initial conditions actually were, or are, or should be for the models) and make meaningful predictions/projections/prophecies about future climate. Quite a few papers were dropping ECS to 2-ish and putting the upper bound well below the AR5 mean estimate. This, on the other hand, pretty much devastates the predictions made using this (IMO frankly statistically absurd) methodology in all previous ARs, as well as almost all of the models.

Personally, I don't take anybody's word for anything in this game. Too many people on both sides talk politics, not science. So I try to look at the actual data and fit it myself, and if I had the patience and time (and the code itself weren't shit and semi-encumbered) I'd even get one of the semi-open GCMs running on my own hardware. Slowly, of course. We lack the computational power to solve the actual problem that needs to be solved under any circumstances, and have basically been solving what we can afford to solve with our fingers crossed that it will give us at least the envelope of future reasonable results. But even if that assumption is true -- and there is no terribly good reason to think that it is -- you can't get the right envelope with the wrong inputs and aerosols have been the unknown elephant in the room for some time now. Well, and water vapor/clouds. The two are right or wrong together, and if aerosols have been wrong water vapor assumptions have also been very wrong.

All of which isn't "denial" -- it is the way science works. And will continue to work regardless of the yammering and name calling (again, on both sides). The dialogue isn't improved by a) pretending that there is no dialogue, that the matter is "settled" and b) by devolving to name calling and invoking a long list of logical fallacies in defence of a political -- not a scientific -- position.

rgb

Comment: Re:Claims should be easily verified (Score 5, Informative) 573

by rgbatduke (#49310291) Attached to: Greenpeace Co-Founder Declares Himself a Climate Change Skeptic

Not historic (read on about low levels in the Wisconsin), but probably low in the Holocene. Part of the issue (and the reason for "probably") is that plant stoma give a different answer than ice cores. Both methods of determining Holocene CO_2 levels have their problems, but arguably the ice cores have more. Since it is low in the Holocene, yes, they were slowly descending. The climate was cooling, culminating in the Little Ice Age, which is still recorded as being very likely the coldest stretch in the last 11,000 years post the Younger Dryas. Since the ocean takes up more CO_2 as it cools, it is not implausible that CO_2 was as low as it had been for order of 12,000 years, BUT plant stoma show CO_2 level varying by almost an order of magnitude more than ice cores, and with a somewhat different mean behavior. So it is possible that it actually varies naturally on a century timescale by at least 30 or 40 ppm and it wasn't an actual low. Still, both are plausible and supported by evidence.

Plants get very sad (IIRC) at around 160 ppm, which is the level at which mass extinction of at least some kinds of plants becomes possible. During the last glaciation (the Wisconsin) the low-water CO_2 level was around 180 ppm, which is, in fact, really, really close to the critical point. Since carbon tends to be systematically removed from the environment by a variety of processes (such as shellfish growing their carbonate shells and a colder ocean absorbing more) we (the planetary ecosystem) might or might not have been in serious trouble in the next glacial episode. More than the trouble caused by the fact that there are all of these kilometer thick glaciers where things like New York and Montreal are today and the pretty serious effect of global cooling by 5 to 10 C in a stretch of time as short as a century, if we can believe parts of the fossil record and icepack cores from places like Greenland.

Finally, there is absolutely no doubt that plants are much happier with 400 ppm than they were at 280 or 300 or 320 ppm. Plants grow faster, are healthier, and are more productive at higher CO_2 levels. This is known both from lab work (greenhouses with controlled CO_2) and from observations of crop yields and tree growth rates in the real world. Plants would be happier still with 1000 ppm. Over almost all of the last 600 million years, atmospheric CO_2 has been anywhere from 1000 ppm to 7000 ppm. Levels as low as 300 ppm are extremely rare and yes, probably dangerous to the biosphere.

We will now return to your regularly scheduled rants about "warmists" and "deniers" and hatin' "C-AGW" without questioning the "C".

rgb

Comment: Re:So they are screwed (Score 1) 214

by Areyoukiddingme (#49294855) Attached to: Billionaire Teams Up With NASA To Mine the Moon

Since the authorization is for exploration, not exploitation, and they fall under the umbrella of the USA, they cannot set up a mine on the moon and do anything.

Silly. Ships at sea float around with Nigerian flags all the time, because on paper, the company that owns the ship is Nigerian. Of course the Nigerian company is owned by an American oil company, but it still counts.

So it will be with the Earth's moon.

Comment: Re:Politicians will be stupid but scientists/techn (Score 1) 356

by Areyoukiddingme (#49294461) Attached to: New Solar Capacity Beats Coal and Wind, Again

"Due to its low specific energy, poor charge retention, and high cost of manufacture, other types of rechargeable batteries have displaced the nickel–iron battery in most applications" The poor charge retention seems to suggest that the in-out efficiency will be low as well.

Two thirds of that is FUD. Low specific energy is the only valid reason in that list, and "low" is very much a relative thing. A bank of nickel-iron batteries big enough to power your house still takes up a small corner in that house. It's not like you have to fill your basement with racks and racks of them.

"High cost of manufacture" is blatant bullshit. It's nickel and iron and a case and some water and some potassium. The process can be 100% automated and involves forming materials as complex as... nickel-plated steel tubes (*gasp*). They're expensive because there has been no mass production for decades, because they work too well. They're a lifetime battery with only a tiny amount of care, and can retain 40% of their rated capacity for a century even if they're abused (there are original manufacture Edison Company nameplate nickel-iron batteries still in operation today).

Charge efficiency is a little poor in the original Edison cell design, at 65%. Discharge efficiency is 85%.

Do you want a nickel-iron battery in your cell phone? Definitely not. Charge density is the only thing that matters in that form factor. Do you want nickel-iron in your car? Still no, because again, density is really important. Do you want nickel-iron batteries in your basement? Oh hell yes. 100% non-toxic materials, the potassium-hydroxide electrolyte isn't nearly as hazardous as sulfuric acid, a float charge all day long doesn't hurt them at all (unlike every other chemistry), and most importantly, you buy them ONCE, install them, and use them, for decade after decade after decade, without substantial charge capacity loss.

The biggest failing of nickel-iron batteries is they are incompatible with capitalism. No constant revenue stream for replacements.

Comment: Re:Why Force Your Children to Live in the Past? (Score 1) 734

by Areyoukiddingme (#49253609) Attached to: Ask Slashdot: Should I Let My Kids Become American Citizens?

Now your just making bullshit up. Dead last? You can't even make up a plausible lie.

True, with the caveat "in the developed world." Obviously not true if you include undeveloped countries. The difference is also not very large. A couple years, at most, and only a year, for most. Still technically true, and not just a statistical fluke.

Comment: Re:Unfair comparison (Score 4, Interesting) 447

by rgbatduke (#49246665) Attached to: Homeopathy Turns Out To Be Useless For Treating Medical Conditions

It's not that small.

Placebos have as high as a 30% response rate for many things. That's why the gold standard is to compare double blind placebo controlled data. It isn't no response rate that matters, it is the response rate relative to sugar pills that somebody tells you are medicine. Telling somebody that roasted rat pellets (convincingly) are medicine means that you will get a positive response.

Add to this data dredging, confirmation bias driven studies, tenure decisions made in your favor only if you see a positive response in your new cancer treatment, and the fact that "significant" is generally a statistical absurdity like p = 0.05, and it's no real surprise that we end up with lots of (ultimately) silly conclusions.

rgb

Comment: Re:From the linked information (Score 1) 267

But the people who actually own Teslas are seeing them to be closer to half the cost of the car (Model S, which I believe is $80,000, so $40,000 for the pack).

Eh? Based on what numbers pulled out of whose ass? No Model S battery pack is out of warranty yet, so no one anywhere has paid out of pocket for a replacement battery pack.

The sales guy's are the only figures, at the moment. When the warranty begins to run out, then we'll see, but by the time that happens, the current conditions will not apply. Tesla's Gigafactory will be online and the world supply of lithium ion cells will have doubled. That can't help but put downward pressure on the price of cells and packs made of those cells.

In any case, $40,000? I call bullshit.

Comment: Re:Let's do the Chicken Little Climate Change danc (Score 1) 235

by rgbatduke (#49242819) Attached to: El Nino Has Finally Arrived, Far Weaker Than Predicted

It's especially not significant compared to the ~7% annual variation as the Earth swings in its elliptical orbit. This 91 W/m^2 is truly the elephant in climate forcing variations -- everything else is comparatively a mouse.

Interestingly, the annual temperature variation of the Earth countervaries with this -- the Earth is coldest when it is closest to the sun and warmest when it is furthest away. This is spite of the fact that in the tropics where the variation due to inclination is the least and one expects the strongest effect there is no major shift in land/sea area exposed and hence the albedo difference that supposedly cancels the more than 45 W/m^2 peak insolation relative to the mean.

The climate really is a highly nonlinear system and not all of it makes sense in terms of naive models. Yet. Pretending that we understand it when we don't may sell catastrophe (and hence research into contingent catastrophe), but it doesn't do science itself any big favors.

rgb

Comment: Re:FCC CREATES Internet monopolies (Score 1) 234

* The city would completely control my access to rights of way and pole attachments, and would be motivated to keep me from getting that access or make it expensive;

So, exactly the way it is right now, except right now they do it at the behest of lobbyists, rather than their own interest. No change, from your perspective.

* The city would engage in horizontal monopoly leverage from its other monopoly businesses (trash, water, sewer, and in many places energy) and would enjoy cross-subsidies from them; for example, it wouldn't have to build a new billing system but could use its existing one;

While true, just how much did setting up and running your billing system cost you? Not much I bet, especially compared to the labor required to install hardware.

* The city could also use its ability to tax, and bonding authority, to obtain capital for the buildout at bargain rates;

Yeah, that's a bummer.

* The city, with its deep pockets and by expending some of that capital, could engage in predatory pricing, offering its service below cost due to taxpayer subsidies. It could do this at the outset, to take customers away, or possibly permanently;

I'll stop with the point by point here, because many of these points can be rolled together.

It very much depends on the model the city uses to "be an ISP." The Swedish model seems to work extraordinarily well. The city isn't really an ISP, in that case. They own (read, install and maintain) the wires/fiber that reaches individual subscribers, bring the other end into a building, and say "have at it" to people like you, who then offer the actual Internet service. You run the billing still, you run the routing and traffic shaping, and you arrange for and pay for the uplink to the Internet at large. You pay the city some fixed amount per subscriber, but set your own rates.

That's the model any of us who are paying attention would like to see. It provides all the room in the world for competition, while solving the natural monopoly/conflict of interest problems in the last mile. It allows competitors to differentiate themselves as much as they like. The city provides a dumb pipe. The ISP provide services through that pipe. Don't want IP TV? Pick an ISP that doesn't provide it. Want IP telephony? Pick an IP that provides it. Want a really cheap, slow connection? Pick the ISP that pays for a tiny uplink to save money. Sure the last mile fiber will be radically underutilized, but Grandma Jones doesn't use Skype video, so she doesn't care as long as her Facebook games work. (Though I suspect the old Grandma Jones stereotype is fading fast. She wants to be able to see the grandbaby, and Skype and Facetime are making it easier and easier.)

Will there be cities that provide the whole service? Probably so. In that case, yeah, you won't be competing. No one will. That leaves a monopoly provider, but in this case it's a monopoly provider that doesn't have a major profit motive, and does have to answer to votes quite regularly. They're not as unaccountable as you make out. In time, those votes may result in changes. It's quite possible that cities that initially build themselves out as the ISP will transition to the Swedish model, just to avoid the hassle.

This ruling will allow cities to actually try. We'll see how it plays out.

Comment: Re: Pacific Decadal Oscillation (PDO) (Score 1) 235

by rgbatduke (#49218743) Attached to: El Nino Has Finally Arrived, Far Weaker Than Predicted

When in the history of science has it been reasonable to call somebody that disagrees with your interpretation of the science a "denier"?

As for sea level rise, the evidence is that SL is rising and indeed has risen roughly 9 inches in the last 140 years without anybody really noticing. It is projected to rise another 10 to 15 inches in the next 85 years -- if warming proceeds as expected (outside of egregious exaggerations pushed by e.g. James Hansen). This wasn't catastrophic in the past, is not likely to be catastrophic in the future, although it can certainly be problematic for some very low lying land areas, especially ones also afflicted with subsidence (as subsidence and uplift are substantial ongoing coastal processes independent of AGW). "Catastrophe" involves melting either Greenland or Antarctica, and neither one is melting at anything like a substantial rate.

Methane is a pet peeve of mine as well. Most of the methane is tied up as clathrates at enormous pressures and extremely cold temperatures in the ocean. Most of the ocean is within a hair of 4 C and isn't going to warm enough to care about no matter what on any reasonably short time frame (centuries, millennia). Most of the recent papers on the subject are finally coming to recognize that this is a fantasy -- if bottom warming alters methane production, it won't be because of CO_2 but rather geothermal activity, e.g. vulcanism. Also, the ocean eats methane -- they went to study methane released in the Gulf Oil disaster and found rather to their surprise that there hardly was any -- most of it was eaten en route to the surface. In the atmosphere it quickly rises and is broken down by UV and ozone. It isn't clear how much methane would have to be released, how steadily, to maintain an increasing profile in the atmosphere but it is likely to be a big number.

If you want to pick on a thing that could be at least locally catastrophic, I'd go for increasing oceanic CO_2 lowering the basic ocean pH over time. I'm still skeptical of any global disaster, because I think the biosphere is a lot more resiliant than that (and because for most of the Earth's past history over the last 500 million years CO_2 has been over 1000 ppm and shellfish in general did fine) but aragonite etc is at least in principle vulnerable in organisms that rely on it. There, as you say, if things change too quickly some species in some locations might -- big word, might -- face extinction.

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