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Comment Damage is not binary (Score 1) 325

People need to realize that the effects of global warming are at this point unstoppable. No conservation effort and certainly no carbon dioxide removal program could possibly show an effect for decades. At which point the damage will already be done.

You have just written a false dichotomy; dividing "damage" into a binary: either there's damage or there's no damage, with no significance to degree of damage. That's not the real world. There can be more and less effect; less damage or worse damage.

Some effects of global warming are unstoppable.

At which point the damage will already be done. .

Some damage will already be done.

Money would be much better spent preparing for sea level rise etc than trying to prevent it.

False dichotomy: you can do both. Or, more particularly, different people and different organizations can do either, or both.

Comment Panic attacks (Score 1) 342

I haven't seen any evidence of a "panic attack" by politicians where they "open the flood gates to immigration from the poorest excuses for countries."

So far, exactly the opposite has been true: recently there has been panic attacks by politicians where they close all the borders to immigration from the poorest countries.

Comment Population control (Score 5, Insightful) 342

This argument just needs to die. It's not going to happen unless we're talking about some sci-fi book/movie. China does this, but they are a communist country too, so their people gave up their choice in any matter what so ever just simply by being born in the country.

To the contrary. You do not need to "give up choice" to limit population. Demographic studies have demonstrated that there are three things that have been shown to reduce population growth.
1. Prosperity. Demographics shows that affluent people, on the whole, have fewer children than poor people. You want to reduce population growth in poor countries? Address the poverty.
2. Education. Demographics shows that educating people reduces the birth rate. Most effectively, educating girls (who in many countries with high population growth have no access to education at all)-- but in general: population growth rate decreases with education.
3. Access to birth control techniques. This actually surprised the demographers, who hadn't predicted it, but the data is pretty firm. Independent of the first two factors, simply give people access to means of control over their own reproduction... and they, in general, have fewer children.

So, that's it: how to save the world: bring people out of poverty, give them education, and give them access to birth control.

You don't need the totalitarian bullshit.

Comment Global means global (Score 4, Insightful) 342

and stop telling us that while every cold year did not refute anything, the hot ones are, in fact, confirming.

No single year that's colder than average in one particular place is significant, nor one that's hotter than average in one particular place. The important feature about global warming (or, if you prefer, global climate change) is the global part.

A year that's warmer than average averaged across the whole Earth is indicative... but not conclusive.

A whole sequence of years that are all unusually warm, averaged across the whole Earth, however: that is significant.

Comment Mars insolation [Re:Plant plants] (Score 1) 215

And to keep the plants powered. Mars is at 1.5AU, which gives less than half the sunlight intensity of earth - your crop would grow very slowly and very small.

Plants grow fine in places that are cloudy. Mars will get on the order of ~250 to 300 w/m2 averaged over a day. Here's a map of the incident solar radiation ("insolation") on Earth:
Mars insolation levels correspond to the light green color. It's no worse the Europe in terms of sunlight, and plants grow in Europe

Comment Re:No Von Neuman Machines yet (Score 1) 215

We don't yet have the slightest notion how to make self-replicating robots. Probably the best we could do is to send up the sophisticated parts, but make some of the physical chassis components from available resources, to reduce somewhat the mass required from Earth.

What available resources? Mars has no petrochemicals. It's very rich in iron, which is certainly nice, and I'm sure there are other metals you can find and mine

That's more or less that I was thinking of when I said you'd bring the sophisticated parts from Earth, but might be able to make the physical chassis and the structural components from available materials. Steel, in particular, is easily available on Mars:

If you needed petrochemicals, you can make hydrocarbons from carbon dioxide. But I'm not sure that this would be my first choice for a resource for making things (although it will, of course, be one of the first resources to be exploited: to make rocket fuel.)

- but doing so needs industrial machines, and smelting/refining equipment, and a lot of power.

Well, yes.

Comment No Von Neuman Machines yet (Score 3, Insightful) 215

They could be self replicating.

We don't yet have the slightest notion how to make self-replicating robots. Probably the best we could do is to send up the sophisticated parts, but make some of the physical chassis components from available resources, to reduce somewhat the mass required from Earth.

Or they could send humans, which are less efficient, but self replicate already.

Raising babies takes a tremendous amount of infrastructure. An adult human is mostly self-sufficient; babies are not. As somebody said, it really does "take a village" to raise a child.

Comment Plant plants (Score 2, Informative) 215

Mars doesn't have dirt- it has regolith, an abiotic rock dust that can't support most plant life, even if it weren't full of volatile poisons

Other than nitrogen, plants don't derive their nutrients from the soil; it's not relevant that the soil is "abiotic". You will have to either supply nitrogen, or else grow plants that incorporate nitrogen-fixing bacteria (e.g., legumes, alfalfa).

By "volatile poisons" I assume you are referring to perchlorates (which aren't actually all that volatile). These can be washed out of the soil. (You'd probably want to do this to reduce the level of salts in the soil anyway).

Growing plants is a technology that is pretty well understood. Soil is unlikely to be the bottleneck. Frankly, the hardest problem isn't going to be the soil; it's going to be the power supply to keep the greenhouses above freezing at night. (Presumably waste heat from a nuclear reactor).

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