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Comment Parent is right (Score 4, Informative) 141

Too bad this is getting downvoted as it is correct. Trees consume very little of the CO2 we produce from fossil fuels, in part because trees themselves produce enormous amounts of CO2 every night, which they then re-absorb during the day.

The vast majority of CO2 fixing occurs in the ocean, not the forest.

NARRATOR: So dense is the Amazon jungle that it has a dramatic impact on the air above it. It starts in the trillions of leaves far below.

We can use animation to show what this invisible process, known as photosynthesis, might look like. During the day, the leaf takes up carbon dioxide from the air, seen here in orange. It converts the carbon into sugar and releases the gas that allows us to burn our fuel, oxygen, seen in blue.

Each one of these trees will release hundreds of thousands of cubic meters of oxygen in the course of its life. And as for the Amazon as a whole, a fifth of the world's oxygen is produced here. But here's the surprise: we will breathe almost none of it. Satellite data and ground measurements reveal that almost all the oxygen the Amazon produces during the day remains there and is reabsorbed into the forest at night.

PIERS SELLERS: With the advantage of the satellites, we can now see that the Amazon basically uses all its own oxygen and uses all its own carbon dioxide. It is, as far as we can tell, almost a closed system, in and of itself, almost.


Comment Nonsense (Score 1) 368

AI, robots, nanotechnology, and genetic therapies will change mankind's future at least as much as electricity, transportation, and communication changed it in the past.

I would also say that the full societal implications of the Internet are just now beginning to appear. It's hard to tell now, in the moment, but the truth is that global societies have already changed dramatically since the Web was launched in 1992. I would argue for the better.

Comment Anthropic principle and observation (Score 1) 145

The anthropic principle* basically states that the fact that we can observe the universe necessarily constrains the observations we will see. In other words, if the nuclear strong force was 100x as strong, no life would exist to observe and measure that. It is really focused on the baseline forces and constants that underlie our understanding of physics.

The anthropic principle focuses solely on actual observed evidence: we can observe that we exist, and we can measure the forces and deduce the constants mathematically.

It does not necessarily apply to the question of life elsewhere in the universe, though. We can guess that the same physical conditions that allow us to exist, will also allow other, similar life to exist elsewhere in the universe. HOWEVER, we do not have any direct observation of life anywhere other than Earth. To the contrary, we have observed numerous objects within our own system and found no other life whatsoever. In addition we have failed to create "new" life in the laboratory from non-living materials.

The scientific statement about life is that we don't know how strong the anthropic principle is--how unique we might be within the universe. We don't know whether there is actually IS any other life in the universe, and we certainly don't know how prevalent it might be. That's not a religious statement because it is strictly constrained by observation. The moment we get proof of life elsewhere in the universe, that will change (unlike a religious statement, which would not).

So while it is true that life must arise spontaneously (since we observe life), there is no proof that it must arise spontaneously more than once. Like you I think it's incredibly improbable that it only arose once in the vast universe. But without observations that support that hypothesis, it is only a guess or personal opinion.

* Not anthropormorphic fallacy--that is the fallacy of assigning human traits to nonhuman things, like rocks or dogs.

Comment Re:The really disturbing part of the story. (Score 1) 284

Posts calling for petitions and boycotts are, generally speaking, usually not technical discussions. Those are the only posts that are getting nuked.

I guess one could make a larger point about censorship in general, but c'mon--it's a tech support forum on Apple's own site. I am sympathetic to idea that maybe Apple doesn't think petitions and boycotts fall within the concept of "customer support."

Comment This is why there are breadth reqs... (Score 2) 594

The narrator as "vain, shallow individual" is entirely a character pulled out of your hindquarters, as there is nothing in the text of the poem to lead to that conclusion.


The ironic interpretation, widely held by critics,[2][3] is that the poem is instead about making personal choices and rationalizing our decisions, whether with pride or with regret.


I'm tempted to bookmark this response as a great example of why engineers should not fear breadth requirements. (I'm assuming anyone with such a low Slashdot ID works in engineering...)

The ironic interpretation is widely held because it's supported not only by the text, but also Frost's own statements, and the broader context of his work--in which seemingly simple descriptive verse hides darker, more complex themes. (A major reason why he is held in such high regard.) This particular poem is a common subject for lessons on critical analysis of literature. The key starting point is that first-person narrators are not necessarily reliable.

Comment Food production is already 1% of US GDP (Score 1) 482

For instance, if food production shrinks to 1% of our economy

This is where the author lost me. The agricultural sector is already 1% of the U.S. economy.

I largely agree with what you're saying but I will add that the "service sector" includes not just actual services (like health care), it also includes the entire information economy, and pretty much all entertainment. This is important because as humans have to spend less and less time creating the basic necessities of life (food, shelter, clothing, etc), we will have more time to spend on entertainment and information--the value of which has little to no correlation with energy cost. I mean, it takes a certain amount of energy to create and play a video game, but different games can create wildly different levels of economic value, for about the same level of energy usage.

Comment Not impossible, just imaginary (Score 1) 482

Endless growth is not totally impossible, it's just imaginary. This distinction is important because our modern notion of economic value is also increasingly imaginary. Thus there is no reason economic growth must be limited.

The funny thing about the blog post is that the author does not seem to realize the extent to which first-world economies have already made the transition he supposes. Services already make up almost 80% of U.S. GDP for example, while agriculture has been reduced to only about 1%.

Comment Simple logic (Score 1) 291

I agree with these notes and I would add: The conclusion of the report seems to fail on simple logic.

If people who pirate are more likely to buy, then we would expect to see much higher content sales today than 10 years ago, since much more content is pirated today than it was 10 years ago.

But as you point out, what we actually see are *lower* content sales in most digital creative industries. The conclusion from this simple correlation is that at best piracy does not help sales very much (if we stipulate some other unknown factor that depressed sales), and at worst it harms sales.

Comment Re:LOL! American Freedom! (Score 1) 212

Yeah, and then a bird craps on your head and it starts raining and just then the phone rings and it's your dad: "You're adopted. And we never loved you." You look down and there's a dog peeing on your leg. A cop is putting a ticket on your car and a teenager is letting the air out of the tires. You look up at the sky and ask "Why, God?" and a skinhead walking by punches you in the throat. You double over in pain and just then a bus roars through a puddle, soaking you in oily black water from the street. The water gets into your laptop and shorts out the battery. You can't update your website anymore and you're on fire.

So yeah--nice freedom of speech you've got there!!!!

Comment Not roundabouts (Score 1) 1173

Roundabouts are more efficient than stop signs or stoplights because they allow drivers to just go whenever they are able, yielding only if necessary.

DC's traffic circles are not roundabouts because they are entirely stoplight or stop-sign controlled. There are no circles in DC that depend only on driver yields for traffic control. In operation they are more like giant complicated stoplight or stop sign intersections than roundabouts. Not to mention that some of them have subterranean "short cuts" under the circle for major streets--which only adds to the driver complexity.

A few DC suburbs have true roundabouts in their neighborhoods, mostly in Maryland in my experience. No idea if they predate 1990.

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