Please create an account to participate in the Slashdot moderation system

 



Forgot your password?
typodupeerror
Check out the new SourceForge HTML5 internet speed test! No Flash necessary and runs on all devices. ×

Comment Re:At this rate... (Score 1) 260

Perfect response from someone who clearly intends to ignore any & all science that doesn't suit their pre-existing beliefs. And it's particularly ironic that your chosen straw man excuse is based on cases where well-established evidence and scientific consensus were also blatantly ignored in favour of the political leader's desires.

Comment Re:Catastrophic man-made global warming (Score 2) 265

Perhaps, perhaps not. Venus is still very poorly understood. In its high temperature environment its conditions are largely self-sustaining (preventing the sequestration of CO2 in rock), although it's also unstable, prone to broad temperature and pressure swings. It also appears to have undergone a global resurfacing event about 300-500mya, if that gives a clue as to how unstable the planet as a whole is. ;) We don't know what caused it, or really anything about it. Part of the planet's properties are now a result of it having lost its water rather than being a cause, such as its hard crust. Obviously its lack of a magnetic field is responsible for its loss of water, but we don't know exactly when or why it disappeared (there are of course theories... I had always just assumed it was the slow rotation rate, but the last research I read suggested that not enough to account for it). Other issues as to how Venus ended up as it did may be related to size - although it's only a bit smaller than Earth, that may be the initial factor that set its fate in motion - for example, its lithosphere in general appears to be thicker and higher viscosity on Earth, which could have hindered or prevented plate tectonics, and thus subduction of carbonates.

Either way, it's a mess now at the surface (though rather comfy ~55km up ;) ). And I'm not so sure I buy into some of the proposed ways to fix it (terraforming). For example, some have suggest mass drivers ejecting the atmosphere. Let's just say you can pull it off, and then you start building oxygen in the atmosphere - what happens next? The crust is something like 7-9% FEO; it's going to rust away whatever oxygen you make in short order.

Interestingly, I'd argue that this is possibly the salvation to Sagan's airborne-microbe concept for terraforming Venus. The main criticism is that if you engineered some sort of carbon-sequestering microbe on Venus (or artificial equivalent), you'd end up with a deep surface layer of graphite surrounded by some hugely hot, dense oxygen layer, and the atmosphere would explode. But that would never happen; at Venus surface temperatures and pressures, the surface rocks would rust away the oxygen as fast as it was created, even in tiny quantities, with the wind blowing the dust around to collect at low/eddy areas. So you're laying down bands of carbon and iron oxide as you burn through the planet's iron buffer. Where have we seen this before? Right, Earth, ~2,3 billion years ago, banded iron formations. Just like on Earth, you'd eventually burn through the iron and start to accumulate oxygen. But by then the graphite is already underground, buried in iron dust.

It's not a fast process. But it has precedent. Microbes already rusted at least one planet, and that planet's surface conditions weren't nearly as favorable for rusting as Venus's.

Comment Re:Catastrophic man-made global warming (Score 0, Troll) 265

I don't know how China managed to melt so much arctic ice, leading to the absurd situation that just a couple days before the winter solstice this year I went on a hike through the snowless mountains in Iceland among chirping songbirds digging for worms. All I have to say to China about this is: Best. Conspiracy. Ever. Well played, China. Well played.

Comment Re:At this rate... (Score 1) 260

I'll see your Nobel Laureate, and raise you 36 Nobel Laureates.

Not that any of their opinions matter half as much as a practicing climatologist's, since expertise in the field is the only way to reach an informed conclusion. By contrast, your chosen authority freely admits:

"I am not really terribly interested in global warming. Like most physicists I don't think much about it. But in 2008 I was in a panel here about global warming and I had to learn something about it. And I spent a day or so - half a day maybe on Google, and I was horrified by what I learned..."

Comment Pretty graph of uncorrected data (Score 4, Informative) 260

Click here to see the uncorrected data graphed alongside the main corrected analyses (source: Berkeley Earth via Ars Technica).

Hopefully this makes it abundantly clear that the raw data still shows an obvious warming trend even before known problems are removed. It also shows how little difference the corrections have actually made, particularly in the last 75 years.

Comment Re:News from other countries... (Score 2) 45

Well, when it comes to space budgets....

NASA: $19,3B
ESA: $5,8B
Roscosmos: ~$2B/yr
JAXA: $2,0B
CNSA: $0,5B official / $1,3B est.
ISRO: $1,2B

It's not just US bias that leads to most stories coming from NASA. NASA really does spend the most on space research and exploration, by large margins.

Still, the public perception is that NASA's budget is far more than it actually is.

Comment Re:such a wonder to mankind (Score 1) 158

Go AIs weren't expected to beat humans for another 10 years though - if that. In 2014 the top programs could only sometimes beat professional-level humans, even with a four-stone handicap, and Grand Masters were a different level, let alone beating the world best. Monte Carlo tree searches make it possible, but they need a good evaluator to guide the simulations. If your simulations aren't good enough then your statistical samples aren't representative, and the best pre-programmed Go evaluator heuristics just weren't in the same league.

AlphaGo's evaluator is what sets it apart, not more searches. It uses layered neural networks, trained against millions of human moves then against each other, to greatly improve their guided simulations, which make it possible to use Monte Carlo searches much more effectively. It was this improved evaluator that enabled AlphaGo to be the first program to beat a professional player (Fan Hui) without a handicap, despite evaluating thousands of times fewer positions than Deep Blue did against Kasparov.

Slashdot Top Deals

In a five year period we can get one superb programming language. Only we can't control when the five year period will begin.

Working...