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Comment Re:Yes... Vwery interesting... (Score 1) 830

There might also be strange coincidences, like a bunch of universal constants that just happen to create a stable universe instead of one that collapses or explodes before anything interesting happens. Or seemingly arbitrary rules such as a constant speed of propagation for light.

Comment Re:Funny (Score 1) 172

You'd think that's a sign that we'd just make all content universally available all at once so everyone can enjoy it and discuss it with likeminded people.

Part of the problem is that "content providers" want to reserve the option to charge _less_ in poorer markets. For example, a lot of U.S. textbooks are sold in China and India at lower prices, albeit on cheaper paper and maybe with a Chinese cover. There is no legal obstacle to importing these books back to the U.S. and selling them at a lower price than U.S. textbooks. So with DVDs, they introduced a technical obstacle: preventing DVDs sold in one region from being played in players made for another region.

With streaming it may be the same thing -- don't allow a streaming account based in one region to be used in another region. I doubt Netflix offers lower-cost streaming accounts in India, but by now I the video producers have the bug for regional segregation.

Comment Re:The MSR is the way to go. (Score 1) 366

Is there anything inherent to these designs that prevents rogue owners from inserting U-238 and producing Pu-239? I haven't been able to find any discussion of this except a note about a French MSR design that uses 50 kg of Thorium-232 and 50 kg of Uranium-238 (not a good sign). If the whole world is going to use thorium breeder reactors, we don't want everyone to be able to kick out the inspectors and switch to bomb-making mode whenever they feel like it.

Comment Re: The most fundamental problem is not the cost.. (Score 1) 366

Breeder reactors by design can convert unenriched uranium into plutonium, suitable for weapons. Right now, 14 countries own or have access to nuclear weapons. Would you want to limit breeder reactors to them? If so, then what should the rest of the world use for energy?

Breeder reactors are not the answer if they can only be used by nuclear powers, and they're not the answer if they make everyone a nuclear power. There's not much room in between.

Comment Re:Bullshit (Score 3, Insightful) 106

Heliostats work by heating a salt to high temperatures then using the heat to power a turbine in a traditional heat engine. The latter tends to be highly efficient (over 90%), while the former is around 75% efficient or more.

I think you're trying to say that mirrors can heat salt with >75% efficiency and heat engines tend to be >90% efficient. The first claim seems vaguely plausible, but the second claim is certainly false. Typical single-cycle power plants have efficiencies around 35%, and combined cycle plants (combustion turbine plus heat-recovery steam generator) have efficiencies up to about 50%.

With a heat engine operating at normal terrestrial temperatures (say 300 K on the cold side and 1000 K on the hot side), the maximum possible efficiency is 70%. To achieve 90% efficiency, the high temperature side would have to be at least 3000 K (half as hot as the sun). I doubt this system is that hot.

Comment Re:Logarithmic (Score 1) 347

I know what logarithmic means, but I was countering the conclusion drawn by huckamania:

The effects of CO2 are logarithmic and most of the heating we should expect to see has already happened.

If we have seen 0.85 degrees of warming and can expect 3.2 degrees, then clearly it is not true that "most of the heating we should expect to see has already happened." The reports I cited factor in the logarithmic nature of warming, but also account for the fact that it takes a long time to reach the final temperatures after CO2 concentrations are increased. The delayed warming exceeds the logarithmic effect, and we can expect much more warming in the future than we've seen already.

Comment Re:The thankless job of solving nonexisting proble (Score 1) 347

Sorry, I don't feel like it.

That is precisely why I am not arranging the links in the pretty little table you want. I have given sound evidence for my position, and don't care to jump through hoops putting them into the specific format you requested. Grow up and read the articles.

Anyone who has made the least effort to study the Earth's climate knows that (a) we are dumping a lot of CO2 into the atmosphere, (b) higher CO2 concentrations will cause the planet to warm, and (c) significant warming could cause serious harm. My "if" condition is satisfied: there is substantial evidence that people are causing climate change and that climate change could cause significant harm.

At this point, the burden of proof is on you. If you think we should do nothing about climate change, it's up to you to provide evidence to support your position, which you have not done and cannot do. This obligation is especially strong given the serious risks involved. If our ship is headed toward an iceberg, we must steer away, even if it is inconvenient. If you want the ship to keep sailing ahead instead, it's up to you to prove the iceberg won't damage the ship. As you say, put up or shut up.

Comment Re:The thankless job of solving nonexisting proble (Score 1) 347

Every one of the links in this thread points to an easy-to-read article referencing a mainstream prediction of temperature trends and later evidence showing that the prediction was right. If you have so little interest that you won't read the articles unless the links are spoon fed to you in a particular format, then there's not much point discussing this with you.

The original predictions cited in this thread were published in Science magazine and several IPCC Assessment Reports. Those sources are at the pinnacle of global peer review and debate on climate change: they represent the mainstream view among climate scientists at the time they were published. They are not cherry-picked studies that happened to turn out right.

If you think it would be easy to retrospectively cherry-pick old studies that happened to be right (or wrong), you will enjoy my challenge to you: please give me one reference to a global temperature forecast published in a peer-reviewed source in the past 35 years that significantly overpredicted global warming. You can refer to the article and its rebuttal using an academic citation, a pretty table of URLs, a fun word game, or any other format you choose.

I would also point out that this debate doesn't even center on the right question, which is: given the evidence we have, what action should we take? If there is substantial evidence that people are causing climate change and that climate change could cause significant harm, then the correct policy is to take action to avoid the harm. The only sound argument for inaction would be compelling evidence that harm will not occur. Do you have that evidence? It's not enough to debate the precise magnitude of the risk. You have to show that on balance inaction can be expected to cause less harm than action. Anything else amounts to hoping the problem will not materialize, and as we know, "hope is not a plan."

Comment Re:The thankless job of solving nonexisting proble (Score 1) 347

It seems you partly agree with my point, which is this: climate change consists of a long-term upward temperature trend, with normal weather variation superimposed on top of it. Thus, you would expect a few up years, a few flat or down years, a few more up years, etc. But over several decades, the trend would be upward. And that is exactly what we're seeing, as shown in the link above. i.e., if 2000-2014 contains 13 of the hottest years of the last 130, then it is clearly part of an upward trend on a 2+ decade time scale, even if temperatures jumped up and down a bit within this 15-year period. Further, since climate change is a multi-decade or multi-century process, we can't ignore it just because the world hasn't ended in the first 30 years. The climate has clearly changed, but the biggest changes are yet to come.

I think you misunderstand some statistical techniques when you criticize instrumental precision. Yes, there are measurement errors at individual sites, and there is no way to measure the whole globe's temperature directly. However, two factors make it possible to estimate the long-term global trend very accurately. The first factor is the use of a longitudinal study format, where temperature is measured repeatedly at the same location. This makes it possible to observe the trend at that site very accurately -- i.e., the long term trend will emerge despite small measurement errors on individual days. Second, even if you can't measure the whole planet's temperature at each time step, you can observe that the weighted mean of your sampling sites is rising. If you choose the sites carefully, and observe them repeatedly, you can estimate the global temperature trend with a high degree of certainty; i.e., you can say that even with random errors in individual measurements, there is a greater than 95% (or 99%) chance that the actual temperature increase is within a certain (narrow) range around the number you've calculated.

It sounds nice to us (as a warm-blooded species who mostly live in colder climates than we evolved in) that temperatures are rising more at night and in winter (exactly what you'd expect if you threw a thicker "blanket" of CO2 on the planet), but that doesn't make climate change any less dangerous. It is still a sudden change in the temperature and weather regimes that human and natural systems have adapted to over thousands of years, and a small change can make a big difference. The difference between the last ice age and today is only about 5 degrees C, and we're on track for a 2-3 degree rise from pre-industrial times. I wouldn't shrug it off lightly.

Comment Re:The thankless job of solving nonexisting proble (Score 1) 347

Are you just having fun, or do you really misunderstand complex systems this badly?

Here is an obligatory car analogy (OCA): Suppose you hitch a trailer to your car and drive it to work every day. Every day you add another big rock to the trailer. After a few weeks, you think, "hmm, my car is not climbing hills as well as it used to, and I would swear it's overheating more often than it used to." But your brother says "nah, those are just extra-steep hills, and it only overheats on hot days." So you keep adding rocks, one a day. After a few more weeks, you say "I'm sure there's something wrong, and I bet it has something to do with those rocks." But your brother says "no way, your car is faster than ever going downhill, and the overheating is just due to hot weather. Last week the weather was cold and your car didn't overheat at all. You keep telling me the car is going to overheat, but it's always done fine. I'm tired of hearing about it." Your brother is right about the variability, but does that mean you don't have a problem?

Comment Re:The thankless job of solving nonexisting proble (Score 1) 347

I don't know which article you're referring to, but honestly it doesn't matter. There is plenty of evidence that the atmosphere is warming, plenty of models that predict or predicted this as a consequence of increased CO2 concentrations, and no credible models that predict otherwise.

I have no idea where you get the idea that "most of the heating we should expect to see has already happened." We are still accelerating our CO2 emissions, and it will take centuries for temperatures to reach their final equilibrium even after we stop. We have seen about 0.85 degrees C of warming already (top of p. 5 here), and if CO2 concentrations reach 2x pre-industrial levels, we can eventually expect something around 3.2 degrees C (middle of p. 1110 here).

Given reasonable grounds to expect serious harm, the correct policy approach is to take action to avert that harm, not to do nothing and hope things will be OK, or to demand exact forecasts of the behavior of a highly variable system.

Comment Re:government science != more money gravy train (Score 2) 347

My point was that academia is no gravy train, and people who believe academics are feathering their nests by peddling climate fear are living in a fantasy world. It takes an incredible amount of intelligence and dedication to succeed in one of these fields, and the people studying climate all have easier, more lucrative options open to them elsewhere.They do this work because they believe in it, just as you do your work because you believe in it (I hope). Sometimes there can be academic pissing matches, but those are no different from the intellectual holy wars around operating systems, flavors of Marxism, etc. The remarkable thing is how much agreement there is about climate change.

In climate change research, as in other fields of science, you gain prestige (and grants) by formulating models that accurately explain the available data, and withstand the scrutiny of other researchers. You do not improve your chances by offering extra doom and gloom.

Further, no climate scientist has ever said we'll be dead in 5 years or anything remotely similar. In this case you're the one offering an extreme position to earn extra attention. Scientists generally say that climate change is a multi-decade process, with potentially dire consequences late in the century. The fact that you are not suffering yet does not refute the drumbeat of evidence that temperatures have risen and will continue to rise until we reduce emissions.

Comment Re:The thankless job of solving nonexisting proble (Score 2) 347

You might also want to take a look at this post (just came across it with a quick search), which notes that a mainstream projection (in Science Magazine) in 1981 has come in very close to actual warming, but a little lower. Or you could look at this post or this post about projections made in 1990 and 1999 which are also coming out right.

More fundamentally, I'd ask you to take a look at the basics of atmospheric modeling, and point out where you think the mainstream models are wrong. You could start with the American Chemical Society's section on "Atmospheric Warming", particularly the Single-Layer Atmosphere Model and Multi-Layer Atmosphere Model. These are pretty easy to understand, and the underlying principles are at least as well established as the other areas of science we rely on for our high-tech lives. If you can't be bothered to understand the basic physical processes involved, you have no business debating climate science.

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