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Comment: Re:Complete article (Score 1) 242

by MightyMartian (#49367331) Attached to: Experts: Aim of 2 Degrees Climate Goal Insufficient

You may not say I'm guilty of a fallacy, I'm saying you are. It's almost as if you think simply stringing long lines of words together in some semblance of a sentence somehow represents a critique. I hesitate to call what you're line of argument has devolved to a game of semantics. More like a game of alphabet soup.

Comment: Re:Complete article (Score 2, Interesting) 242

by MightyMartian (#49367213) Attached to: Experts: Aim of 2 Degrees Climate Goal Insufficient

Are you trying for the Logical Fallacy of the Year Award here? The point of AGW theory is that the changes we are seeing are not natural in origin. Instead of playing semantics, deal with what the theory states. Invoking private definitions is probably the lowest form of debate, because it's useless and accomplishes nothing.

Comment: Re:Complete article (Score 2) 242

by MightyMartian (#49366985) Attached to: Experts: Aim of 2 Degrees Climate Goal Insufficient

I'm sure it's the same down in Washington State as it is up here in coastal British Columbia. Low snow pack means lower river levels, which means potential problems for irrigation in areas under cultivation, harm to fish stocks, and the potential for severe water restrictions in some areas.

I own some property out in a rural area of Central Vancouver Island, and while my house is on a civic water system, my kid and her partner live on the property in a house that gets its water from a creek that flows beside the property. They also raise pigs, using my water license. The creek swells up during rainstorms (like the one we had over the last day or so), but all in all, it's very low compared to other years this time, and I'm seriously worried that we may have to put everything on the civic system, or dig a well, and both cost $$$.

It also brings to mind the previous winter, when we had to put a new water line from the creek into the kids' house in the middle of December. First of all, it was about six or seven degrees celsius (42.8F), and I was literally clearing out the trench in jeans and a t-shirt. The soil itself, a sandy loam common in our area, was damned near bone dry a foot down. The back hoe operator was pretty amazed, and it demonstrated how the 2013-14 winter was very dry (though it did have longer cold spells).

The final anecdote to my story is that I grew up on the property, and when I was a kid back in the 1970s and 1980s, we used to skate at least two to three weeks every winter on the big pond, but now, even in the hardest cold snap, I'd be very nervous about walking far out on that ice. It just doesn't simply get as cold on Vancouver Island as it used to, and all that precipitation that should be hitting the coastal mountains and forming a good snowpack that lasts well into summer is just falling as rain.

Comment: Re:WIMPs (Score 1) 221

by Rei (#49366735) Attached to: Dark Matter Is Even More of a Mystery Than Expected

In fact all forces should get weaker with distance faster in an expanding space than in flat space.

That seems like quite an assumption on your part, if I'm understanding you correctly. We can't just assume that all properties of spacetime are scaling evenly - if they did, then we'd perceive no effect at all.

But perhaps I'm misunderstanding you.

Comment: Re:Still photos (Score 1) 341

by Rei (#49366707) Attached to: Why the Final Moments Inside a Cockpit Are Heard But Not Seen

Some pilots would probably still want the ability to override the limits in an emergency if they feel that they can handle the situation better than the autopilot (for example, if the plane is crashing and the pilot wants better control over where/how to bring it down). If so, then you should make it a possibility to disable the limits, have it such that only *ground* can disable the limits. This would of course impose a delay, but at least overriding the limits would remain a possibility.

Of course, a pilot may try to trick ground into disabling limits (such as pretending to be going down or pretending to have a malfunction), so ground would need as much data as possible to assess whether the situation is legit. Might be tricky... best would be to err on the side of caution and only remove limits if everyone is absolutely sure that this is appropriate, if there's any doubt the answer should be "no".

Comment: Re:Complete article (Score 5, Informative) 242

by MightyMartian (#49366617) Attached to: Experts: Aim of 2 Degrees Climate Goal Insufficient

No kidding. Here on Vancouver Island, other than perhaps a four or five day stretch back in December with sub-zero degrees celsius temperatures, and the odd day here and there of frosty mornings, we literally did not have a winter.

There seems to be this popular attack of AGW that involves "Look outside, if it isn't a desert, all those scientists are evil liars!"

Comment: Re:Complete article (Score 5, Informative) 242

by MightyMartian (#49366607) Attached to: Experts: Aim of 2 Degrees Climate Goal Insufficient

Because the changes in this case are not natural at all?

Saying "climate always changes" is like saying "water always flows", and then promptly putting a firehose in your living room and then turning it on. I realize you think this is a great rhetorical trick, but that's all it is.

Comment: Re:Wrong Focus (Score 1) 93

by Rei (#49366605) Attached to: SpaceX's New Combustion Technologies

Not today. But maybe in the future. If you can develop a crazy-power-dense energy source and cooling system, you could probably do it with a MPD thruster. The research I've seen on MPD thrusters operating in pulsed mode yields crazy output relative to the mass of the thruster. But you can't run it continuously because it'd overhead and take way too much power. But who knows about the future? There's the potential for extreme heat conductors like isotopically pure diamond, maybe a some kind of fission fragment reactor with a deceleration grid for power...

(of course, if you have a fission fragment reactor, at least when you're in space itd be best just to jet your fragments rather than use them to power a MPD thruster...)

Comment: Re:It is (Score 2) 93

by Rei (#49366565) Attached to: SpaceX's New Combustion Technologies

I hope they simulate propane too, not just methane. Propane has some really interesting properties as rocket fuel but have (like methane) never gotten much research. But now there's a big rush to research methane as fuel based on the concept of generating it on Mars - so propane still gets left in the dark.

Methane's ISP is only very slightly better than propane's - 364,6 vs. 368,3 at a 100:1 expansion into vacuum and 20MPa chamber pressure. But propane at around 100K (note: not at its boiling point, 230K) has far higher density (782 kg/m^3), closer to that of room temperature RP-1 (820 kg/m) then that of boiling point methane (423 kg/m^3), which reduces tankage mass and cost. 100K propane's ISP is of course better than RP-1's 354.6 in the same conditions as above. Plus, its temperature is similar enough to your LOX that they can share a common bulkhead, which reduces mass further and simplifies construction.

Hydrogen generally is the easiest fuel to synthesize offworld. Methane is generally second, and propane third. Hydrogen is often rejected as a martian fuel because of the tankage and cooling requirements. Methane can be kept as liquid on Mars with little cooling in properly designed reflective / insulated containers - but so can 100K propane, in similar conditions, but with significantly smaller tankage requirements.

It seriously warrants more research, I tell you what.

Comment: Re:Just looked her up (Score 5, Informative) 242

by Trepidity (#49366473) Attached to: Experts: Aim of 2 Degrees Climate Goal Insufficient

The area of geography she studies is how communities/economies are impacted by and adapt to changes in prevailing climates, which seems pretty relevant, depending on what question you're asking. She would be a poor authority on questions like modeling the impact of CO2 on weather, but more within her area if asking questions like, "how easy/difficult would it be for Indonesians to adapt to a 2" ocean-level rise?".

In terms of the IPCC reports, the research/authorship is divided into three working groups: #1 studies the underlying science; #2 studies impacts & adaptation; #3 studies possible mitigation strategies. She's part of #2.

I never cheated an honest man, only rascals. They wanted something for nothing. I gave them nothing for something. -- Joseph "Yellow Kid" Weil

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