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Comment Re:RAM latency is not getting much faster (Score 1) 92

Replacing hard drives with SSDs still leaves another bottleneck. The disks have to connect to the cpu somehow. If they are internal (as in a home pc), then you only get a few disks, but they connect at PCIe speeds. If you need more disks, you go to a SAN. But then you're putting your disks at the end of *network* latencies; there's definitely a wall there. You can't cache your way out of the transmission delays on the SAN... Other solutions are used which essentially move the software and/or data closer to the hardware.

Comment Causation, CO2 and Warming (Score 5, Insightful) 132

[quote]How do we know the CO2 spikes caused the warming? Perhaps the CO2 resulted from increased biological activity occuring as a result of the warming. [/quote]

CO2 is a warming gas in the atmosphere; in the absence of any other changes, adding CO2 will warm the atmosphere. However, as the article notes, we don't know what caused the quick ramp-up of CO2, and we *do* know that other factors (both cooling and warming) were in play. We also know that over time the atmosphere warmed enough to end the ice age in question.

What is safe to say is that CO2 has a warming effect, which could be counterbalanced *and* added to by other factors. It's the overall balance of these things that tilts the scales one way or another. CO2 is just one piece.

But it's not mistaking correlation for causation to note that adding CO2 to the atmosphere will result in increased warming. That's just basic physics. The fact that it could be offset by something else is immaterial to your point.

Comment Re:Talking Point (Score 2) 427

That argument that deep austerity is needed is bogus, however. For years, economists and climate scientists and even skeptics have been arguing that whether or not the problem exists (okay, well, now they usually admit it exists), there is an entire new economic sector that can be opened up to private businesses - climate change mitigation. And that is a net *positive* to the global economy, for the economy as well as through the development of new technology. The fact that if bad things are averted we also gain economically from avoiding them is icing on the cake. The downside? All the major fossil fuel industries are looking at a "co-opt or die" scenario. Cui bono?

You can do this without extreme taxation or austerity, IF you start reasonably soon (in the next few years would be good - we passed ideal a few years back). It's the fear and exaggeration of the costs, largely put out by fossil industry interests, that is delaying change.

So if you really do just tune out and think of nutbar extremists when you consider the costs of this, what you're selecting is guaranteed to be the most expensive path through the next few decades. If you're *lucky*, the cost of that will be minimal as thousands of climate scientists are proven to be wrong. But if you're wrong, well.. That's when that choice gets ugly for your kids.

How much are you willing to be that the climate scientists and their peer-review system are so totally corrupt and incompetent that they are completely wrong? Your future, and your kids and grandkids futures? Hey... Go for it. Maybe modern climate science is the equivalent of catastrophe geology up against Alfred Wegener. But... That's a huge bet to make against the professionals.

Comment Re:Global Temps (Score 1) 427

Where's the hiatus in the warming of the oceans? There's a lot more short term variation in atmospheric warming, but given that the oceans have *not* seen a hiatus, it's clear that that is simply a temporary cooling signal added to the mix. This is what should concern you, because when that cooling signal fades out, the warming in the atmosphere will be back, and possibly at a faster rate than before. In effect, we're getting temporary relief - don't think it's a permanent thing, because if we were really cooling, the oceans would show it unequivocally.

Comment Re:Nearly 3 parts in a million (Score 2) 427

Further, the cite you gave actually reiterates what I'm claiming.

"The growth rates of CO2 concentration have increased in recent years. The distribution of CO2 growth rates differs regionally due to the variation of source or sink. And the spatial variation of CO2 concentration is small compared to that of fluxes. Because the atmosphere is an excellent filter of spatially and temporally varying surface fluxes, integrating short-term fluctuations while retaining the large-scale signal. High growth rate in East Asia has been associated with high growth rate of fossil fuel. And high growth rate in South America is due to decreased biosphere uptake of grass/shrub region in Brazil and increased wildfire release."

"...retaining the large scale signal." That is, the global signal of increasing CO2 is not knocked down by regional or local variations.

Comment Re:Nearly 3 parts in a million (Score 2) 427

You showed no evidence that the global CO2 measurements are inaccurate. But luckily, we have satellites that back up the ground collections, and agree with them. Their coverage is global.

Bear in mind that while there are local variations of CO2, the atmosphere is quite well-mixed, so you don't *need* a sensor every 100 square km or whatever to determine what the average CO2 levels are. Differences settle out regionally and globally, and that's backed up by the fact that the satellites agree with the ground station average quite well.

Comment Re:Nearly 3 parts in a million (Score 5, Informative) 427

Here's how it's measured at the Mauna Kea site. Accuracy is to within 0.2ppm, 1 standard deviation is 0.26ppm.

So yeah, we know it's accurate because it's using the same techniques and technology used all over the world to measure gas fractions per mole of various gasses in many different applications. If the CO2 measurements for climate were wrong as you suspect - "rounding errors" or the like - then people would be dying left and right due to anesthesiology mismeasurements; chemical manufacturing would have far higher error rates; and other very visible and common manufacturing processes would be far less reliable than they are today. This is solid measurement technology.

Human civilization developed at about 275ppm of CO2. It took us from the dawn of civilization (first use of fire, you could argue, so over 400,000 years) to the early 19th century to budge the needle beyond small natural variations from 275ppm. From the 1820's to 1910, just under a century, we gained 25ppm. From 1910 to 1950 - 40 years - we gained 40ppm more. From 1950 to today, we've gained another 50ppm and are currently increasing at about 2ppm per year. 400,000 years - tiny amounts of change. 190 years - 33% increase; that's got to register, since CO2 drives the atmospheric temperature as the greenhouse gas with the most effect.

The problem is that we are now entering a climate regime which humanity has never been in before. Our entire civilization has been built on stable climates, and that's true of the past, too. We have many, many records of civilization which did poorly and even failed when their climate changed by an amount that is a small fraction of what we're doing now. Civilization will not collapse tomorrow, or in a decade, or in a century. It will simply become more expensive, dangerous, uncomfortable, impoverished and unstable than it is today. If you're comfortable with that as the future to leave to your grandchildren, well, more power to you. I hope you build your bunker deep.

Ignoring a problem that will lead to massive changes in the world is perhaps the least conservative action possible. The fact that we are uncertain as to the total effects of these changes down the line, but we know we're messing with the entire planet, means that inaction is even *more* dangerous, because of the possible consequences. So the claim that we need to wait before doing anything is a radical, not conservative, approach.

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