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Comment: Re:Good Luck (Score 1) 319

by Irate Engineer (#48770281) Attached to: How Close Are We To Engineering the Climate?

Well, that's because no one knows what constitutes a "massive perturbation". Some think dumping CO2 into the atmosphere at a rate mutliple times faster than the environment's ability to absorb it is not a big deal, no action required. On the other end, some folks think we should all stop exhaling, now. Intermediate remedies include expensive technologies to mitigate the perturbation. Any solution within that broad spectrum of "solutions" is going to cost dearly, and there is no way to know if they would even work.

We don't know for certain that doing anything is better, worse, or neither as compared to the immediately inexpensive option of doing nothing.

My opinion is that since the perturbations being produced by humankind (e.g. CO2) are on the order of the natural inputs, so that it seems likely to me that we are affecting the climate in some manner. However, there is no concrete proof one way or the other, so my opinion may be quite wrong. All there is is a large number of climate model results, many poorly reported as being accurate without qualification, all swirling in a shitstorm of money and politics, with cherry-picked results being used to support chosen agendas. I really don't see a scientific / technical means to cut through this Gordian knot.

Comment: Re:Good Luck (Score 2) 319

by Irate Engineer (#48770053) Attached to: How Close Are We To Engineering the Climate?

Climate 'scientists' might confidently state that the world will warm by X.YZ degrees in the next 20 years. What they don't ever tell you is the uncertainty in their prediction, basically because it is nearly impossible to quantify.

Take a look at these climate model results:

http://www.ig.utexas.edu/people/staff/charles/uncertainties_in_model_predictio.htm

Which model is closest to correct? Each model makes large numbers of different assumptions about how to mimic radiation, atmospheric turbulence, adequate atmospheric and terrain resolution, and any number of other phenomena. As the actual system is highly nonlinear, even a small uncertainty in the initial conditions can lead to wildly different results even if we had all of the equations exactly correct (which we don't, most are modeling approximations to make the problem tractable).

The best that can be said is that it seems probable that the Earth will be getting warmer. The questions are how much and how quickly? Having a number of predicted outcomes means that there is a range of policy decisions, and politicians can cherry pick the outcomes that resonate with their ideology. If a politician seizes on a prediction that indicates that warming isn't a big deal, they will push for the status quo, especially if the are already benefiting from the status quo. Or maybe they will seize the worst case outcome which suggests major societal upheaval is required to remedy it.

Also, as it is a chaotic system, there really is no way to determine if your attempts to control it were even meaningful, even in hindsight, as chaotic systems change non-linearly without human input. That is the argument of the folks who believe that AGW isn't occurring because the world was warming before humans came along. Others think it's all our fault. Without the ability to spin up a human-free Earth 2.0 as a control, it is very difficult to tease apart what is what.

Comment: Good Luck (Score 5, Insightful) 319

by Irate Engineer (#48768677) Attached to: How Close Are We To Engineering the Climate?
Trying to actively control a massive, chaotic system is not going to end well. The only stable configurations that pop out of computer models of the climate are the snowball Earth and the Venus 2.0 scenario. The only right way to play is to stop applying massive perturbations to the system and realize that even then the climate will change.

Comment: Re:Deja Vu (Score 2) 151

They want to maintain visual on the 1st stage. The aerodynamics of the high altitude, high Mach number deceleration burns is probably the most important thing they want to study. They need to understand this well for the present objective of controlling and landing the stage, but the aerodynamics is relevant to semi-powered descent of the Dragon spacecraft onto Earth and especially Mars.

Here is some footage of their last landing attempt

https://www.youtube.com/watch?v=_UFjK_CFKgA

This is what SpaceX ultimately is aiming for - a spacecraft that can utilize drag and propulsion in varying proportion to land on any body in the solar system, no parachutes

https://www.youtube.com/watch?v=Cf_-g3UWQ04

Comment: Did Everybody at /. have a Bad Christmas? (Score 0) 62

by Irate Engineer (#48714749) Attached to: Finnish KRP Questions Suspected Lizard Squad Member

Geez, a script kiddie denies all you Slashdotters time with your new shiny Playstations and XBoxes on Christmas morning and you are all howling for blood.

Not defending the kid or anything - he'll be an ant squashed under a steamroller in a few months I'm sure. But some of you guys need to shut off the consoles, get out of the basement, and take a deep breath of perspective.

Friction is a drag.

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