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Comment Re: We're not getting hotter (Score 4, Informative) 292

The point of the NYT article is that the data clearly says that hot weather extremes have been increasing and cold weather extremes have been decreasing. That's not really debatable, it's hard numbers.

I'm currently looking for global daytime temperature trends and will update soon. The US data, while interesting isn't necessarily speaking to global trends, and the warming/cooling trends are highly inhomogeneous. In fact the graph you point to specifically says that the Southern Hemisphere didn't see that cooling.

Comment Re: We're not getting hotter (Score 5, Informative) 292

What you're seeing there in the 20's/30's is the dust bowl that wreaked havoc on the central US during that time (high heat, vast drought). It is really interesting to see that. But it was a regional effect. Globally the story is different.

A related important point was well explained recently by NYT: extreme high temperature events are increasing in frequency.


Comment Re: An investment firm? (Score 5, Insightful) 292

I don't know about this particular investment firm, but investment and insurance firms are actually quite well equipped to think about risk, which is really what climate change is about from a financial perspective. They inherently need to be able to think rationally about climate predictions, assess the statistics/uncertainties behind them, and come to conclusions about where and how to invest in the long run. For example, what's the risk/reward for an investment firm to invest in an African company if there's an X% chance that company's location will be uninhabitable in 50 years? Or if climate change leads to social/political instability in the area?

For insurance companies, climate predictions tell them how much risk is involved in, for example, real estate purchases on the Florida coast as sea levels rise and extreme weather events increase in frequency.

For them it's all about probabilities - what is the probability that climate scientists are qualitatively right, and if they are, what are the chances of the particular predicted consequences being accurate (and how accurate). Actuaries crunch those numbers and advise their companies to make risk/reward decisions based off of them. One of the hardest parts about these predictions isn't the actual environmental impact, but the social consequences of it, which can have massive financial impacts.

In terms of what the companies know specifically about climate change, I'm guessing they have scientific consultant teams that provide the expertise they need.

Comment Re: Sample bias (Score 1) 213

I don't know, donating because you think your loved one suffered from CTE sounds like a pretty major bias to me.

That's like people donating loves ones' bodies because they think they had a heart attack, and finding that the vast majority did in fact have heart attacks. If the family thought that the person was displaying symptoms of CTE, then the probability of them having CTE is high.

Don't get me wrong, there's almost certainly a massive causation here. I'm just agreeing with the CTE center's director that drawing a numerical conclusion isn't appropriate here. Almost certainly the CTE rate in the NFL isn't 99%...

Comment Re: Sample bias (Score 3, Interesting) 213

But then there's this quote from the BBC article, which makes it sounds like it was from families who suspected that the deceased had CTE

"Dr Ann McKee, director of Boston University's CTE Center, which led the study, cautioned against drawing any immediate conclusions.
"There's a tremendous selection bias," she said, explaining how many of the brains were donated specifically by families who had suspected that their loved ones were suffering from CTE, which researchers believe is caused by repeated blows to the head."

Comment Re: systemic error (Score 1) 143

Agreed that environmental variability gets washed out when someone else does it. My issue is that any bias in the experiment by design gets repeated as well. So if they come to the same result, you're still left with the question of whether this method is simply more precise but biased, or actually more accurate and the old method was biased.

Another way of saying it is that we should be concerned that the new result is not within error of the old result. One possibility is that there was a bias in the old method, or in the new one. Another possibility is that the uncertainty estimate in the old number or new number is incorrect and they're actually within reasonable uncertainty of each other (3 sigma isn't that crazy as it is).

Comment Re: systemic error (Score 2) 143

That's exactly what the last paragraph is about, and the researchers want to have other group try to reproduce it.

Problem is that if this is the only technique that is capable of this level of accuracy and/or precision, then other groups reproducing the result using the same measurement technique will improve the precision of the value (by making the same measurement many times) but not necessarily improve the accuracy. If there's an inherent bias in the method leading to the different answer then it will be reproduced replicate experiments.

Submission + - SPAM: Image and movie written into bacterial DNA

JoeRobe writes: In a Nature paper this week Harvard researchers have used CRISPR to encode an image and a 5-frame GIF movie into bacterial DNA. Importantly, they did not incorporate all of the data into a single cell, but spread it among multiple bacteria. They were then able to "read" the data out with 90% accuracy by sequencing the DNA of many bacteria to reconstruct the image and movie. According to the article, "This work demonstrates that this system can capture and stably store practical amounts of real data within the genomes of populations of living cells".

Comment Re: Data is data. (Score 2) 98

You're right and that's exactly why this interesting. This is the equivalent of someone using a digital camera to record an image being enlarged by an external lens. The camera normally wouldn't have the resolution to resolve the image, but something else is enlarging the image for it.

Same thing is happening here. Without gravitational lensing the image would take up, say 10x10 pixels on the Hubble CCD (total guess) and not be well resolved. But with gravitational lensing that image is now taking up 20x200 pixels (also a guess but the point is that it is significantly more pixels). So the lensing is giving them more information than they would have had. But the information is coming at the cost of the image being warped. Their hard task isn't interpolation/extrapolation, it's using understood physics and probably a lots of assumptions to back out what the unwarped image looks like.

Comment Re: Greenhouse effect (Score 1) 214

I think the origin of the question about emissions per unit energy is in the context of whether going to hydro would reduce climate impact if there are methane emissions from hydro. Hydro is 6% of total US electricity generation, while natural gas is 34%. 34:6 is a much smaller ratio that 32:1.3, so answering the original question, methane per unit energy is much smaller for hydro than for natural gas.

Methane per unit energy is only a fraction of the story, though. In terms of benefit for the climate, hydro wins hands down because of CO2 emissions from O&G combustion. That's not to say that methane from hydro should be ignored, just that the climate impact per unit energy of hydro is less than that of gas.

Comment Re: Greenhouse effect (Score 1) 214

Possibly, I don't know enough about what the seaweed is doing in the gut to say one way or the other. It could be shutting down the methanogenic bacteria completely, or altering their chemistry, or adding methanotrophic bacteria to offset, or changing the way the cow ruminates, to name a few possibilities. Maybe the mechanism is already known, but I don't know it.

The research I'm talking about is identifying the methanogenic bacteria and altering it to stay active in the gut, but specifically shut down the cellular mechanisms responsible for the methanogenesis.

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