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Comment Re:Here's a Good Summary (Score 3, Informative) 235

At the end of the Permian era, 250m years ago, the global temperature rose by six degrees. That wiped out 95% of all life on earth.

That's why people come to that conclusion; it has happened before.

That, and the fact that just a few degrees may well kill off just about all marine life, raise sea levels, create deserts where there's currently farmland, melt the permafrost (releasing massive amounts of methane into the atmosphere, further accelerating global warming), melt the polar ice caps and the glaciers, deforest the rain forests, and basically make the world a hell-hole.

Sure, humanity could possibly survive; but at what cost and what kind of life would it be? We can't build AC and heating for the whole ecosystem...

Here's an interesting doomsday summary, degree by degree, from one to six degrees: http://globalwarming.berrens.nl/globalwarming.htm

Comment Re:Skyrim (Score 1) 669

Just the other week I actually completed the main quest line in Skyrim for the first time - and then I looked at my Steam stats. 330 hours played...

And that's without any of the DLCs :)

Quite looking forward to Elder Scrolls Online now - the PvP looks excellent from what I've seen :)

Comment Re:Cloud formation albedo (Score 5, Insightful) 378

First, is the planet getting warmer? On that I'd say there's general agreement, although it is not a 100% consensus.

It's a 99.something% consensus, which is as solid as any consensus among a large population is ever going to get. Out of 13,950 peer-reviewed climate articles from 1991-2012, only 24 reject global warming. (source)

Second, if it is getting warmer, is it caused in large part by human activity or is it part of some natural variation? This is the sticking point. If it's part of a natural variation in temperature -- and I will point out many such variations have happened in the past few million years, all without any input from humans -- then there is no need for us to radically alter our life to stop it because such actions will have no positive climatic effect while having a signficant negative effect on quality of life.

All the evidence we have for previous natural variations show them to be slow (or extremely rapid, as in catastrophically rapid - impact events or super-volcano eruptions); the changes we're seeing today is way too rapid to conform to any known natural cycle. The difference, of course, is that we're around and actively adding greenhouse gasses to the atmosphere. In short, not a "natural variation".

Third, if it is anthropogenic, what should we do about it? Curtainling greenhouse emissions is an obvious choice, but is it the best one? How severe are the predicted warming effects? The economic and socio-political upheavals from drastic policy changes might be worse than adapting to a changing climate. And how much confidence can we have in the predictions regardless of how severe (or not) they may be?

We don't know; that's the problem. We don't have any crystal balls, so we don't know what the most effective strategy is, or exactly how severe the effects will be. What we do know is that large climate changes historically have been responsible for some of the most drastic extinction events we know of. And it's pretty easy to speculate about what a massive dying-off of e.g. marine life would do to coastal communities - as is the effect on the same communities of rising sea levels.

These are not minor issues. They deserve to be studied and debated *in depth* before drastic action is take, if for no other reason than to determine that we're taking the *most effective* action possible. This whole "the debate is settle and if you don't agree with us you're a denier" smacks of the same kind of thinking that gave us an Earth-centric cosmic model and burned "deniers" as heretics.

No, these are not minor issues, and the ramifications of the decisions are huge. In the end though, doing nothing is probably the worst decision; there is a tipping point somewhere (the edge of the cliff, so to speak) which going past that there is no turning back. More research and discussion is always welcome, but that should not and cannot stop us from starting to act - if nothing else to slow down the rate at which we're approaching that tipping point.

The analogy with the earth-centric cosmic models and burning of a few heretics is really stretching it when we're talking about the possibility of mass extinctions of not only humans but a lot of other species as well.

The earth will survive, and life itself will survive. The question is, will we? And even if we do, in what kind of society? One that has planned for such an eventuality, or one that has had to just react to it. One is liveable, the other is a post-apocalypse society; I know which one I'd rather (have my kids) live in.

Comment Re: A looping simulation, apparently (Score 2) 745

Agreed, that was sloppy of me. "Cogito, ergo sum" is however used as a stepping stone for Descartes to "prove" that reality is not an illusion, since sensory perception is not an act of will. Therefore they are external to the thinker, and there exists an external world that provides the thinker with these sensory perceptions.

Comment Re:A looping simulation, apparently (Score 0) 745

Simulation hypotheses area as old as philosophy; Parmenides, Zeno and Plato all had their own pet hypotheses that basically amounted to "reality is an illusion". Descartes, of course, had his "Cogito, ergo sum" as his final defence against reality being an illusion.

In short, it's nothing new - the idea is well over 2,000 years old and it has a major, major issue: It's unverifiable - it's like asking what's outside the universe; the question doesn't make sense.

Comment Re:sure jQuery is a hack, so is most tech (Score 1) 573

The hour hand moves around the clock face one complete revolution in 12 hours. Which means that in 30 minutes it should have moved (360 / 12 / 2) = 15 degrees. If it hasn't moved 15 degrees in 30 minutes, it's broken. It should not be pointing directly at 12 if the time is 12:30, it should be pointing halfway between 12 and 1.

How do you know it's not 11:30?

Comment Re:sure jQuery is a hack, so is most tech (Score 1) 573

On a working analog clock when the minute hand is pointing straight down, the hour hand should point in-between two hour positions.

In your example, 12:30 am/pm, a working analog clock would show this by having the minute hand pointing straight down and the hour hand pointing midway between the 12 and the 1.

A clock that shows the minute hand pointing straight down and the hour hand straight up is indeed broken and will never show the right time.

Comment Re:How to make your very own Mars. (Score 1) 161

Perhaps the recent eruptions of water on Ceres are a result of the same limnic eruption phenomenon seen at Lake Nyos.

No, that's not possible at all. The eruptions on Ceres are water vapour, not water, and the current theory is that they are the result of warming on the side closer to the sun.

To be honest, this is somewhat worrying--could this same process occur, here on Earth, if we push the CO2 saturation level too high? A sudden degassing of the atmosphere, into space?

No. If you actually took the time to read the link you've posted twice now, you'd see that limnic eruptions can't occur in temperate lakes because the seasonal shift in water temperature mixes the water and prohibits a colder layer at the bottom building up CO2. Now think about the atmosphere - is it still, allowing this kind of build-up? No, there's weather and wind all the time.

Not to mention the differing levels of CO2 saturation between the lake and the atmosphere.

Has this happened before, in the Earth's history?

Has Earth lost its atmosphere due to "limnic eruptions" in the atmosphere? No. That's crackpot talk. The Earth is too big and its gravity too strong.

Has Earth ever lost its atmosphere? Possibly, but not after the impact(s?) that created the moon occurred, 4.5 billion years ago or so.

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