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Comment Re:No deferring updates? (Score 1) 468

I think the train of thought is a different one. I'd envision something like this:

Ok, our updates break systems from time to time, we could spend more time and money testing it... or we could abuse the home edition users (ya know, the idiots who have no option 'cause their games don't run on any other system) to do it for us. That way we can keep our enterprise users happy without spending a dime more.

Comment Re:suckers (Score 1) 141

If we're going to include damages caused by solar thermal plants, shouldn't we also include the damages we learned about from studying the effects of rapid CO2 emissions during the end-Permian, PETM, etc.?

Since the authors themselves don't come to any real conclusions, and only suggest, again there is no way to estimate. Do hydro dams cause ocean acidification? Does an increase of 50PPM CO2 in the atmosphere cause significant ocean acidification? ... [Jane Q. Public, 2015-06-04]

Jane completely ignores the PETM paper, which has nothing to do with ocean acidification. Hydro dams (which don't and can't contribute most of the power in the USA or in the world) cause ocean acidification only to the limited extent that they rapidly increase CO2 in the atmosphere. So once again it's meaningless to ask if an increase of 50PPM CO2 in the atmosphere causes significant ocean acidification. If that 50 ppm increase occurs over centuries or millenia, it's less likely to cause significant ocean acidification than if it occurs over decades because of the higher rate of increase.

... You have pretty much implied what your answer would be, but the truth is that these are unknowns. ... [Jane Q. Public, 2015-06-04]

No, I've already told you that your second question is meaningless because paleoclimate evidence shows that ocean acidification depends on the rate of CO2 emissions, not the amount in the atmosphere.

There's a difference between "unknown" and "unknown to Jane".

... Be afraid if you like, but I won't join you. While the paper rather vaguely and timidly suggests that there may be danger in rapid changes of pH, the fact remains that corals, many shellfish, and giant ammonoids evolved in the Cambrian Period when CO2 concentration was many times -- in some cases over a hundred times -- what it is today. Correction: CO2 levels in the Cambrian are estimated to be well over 10 times what they are now. Not a hundred or hundreds. Still, we've had only a rise in recent times of roughly 14%... nowhere near 1250% (from 400 to 5000 ppm). [Jane Q. Public, 2015-06-04]

Once again, you're mistakenly calculating the absolute value of atmospheric CO2 ("400 to 5000 ppm") rather than calculating its rate of change. Once again, if atmospheric CO2 increases slowly, ocean pH doesn't change significantly because it's buffered by carbonates and land weathering on long time scales. See Fig. 2 in Honisch et al. 2012 (PDF):

"When CO2 dissolves in seawater, it reacts with water to form carbonic acid, which then dissociates to bicarbonate, carbonate, and hydrogen ions. The higher concentration of hydrogen ions makes seawater acidic, but this process is buffered on long time scales by the interplay of seawater, seafloor carbonate sediments, and weathering on land."

It's incredibly ironic that Jane Q. Public and Lonny Eachus both point to paleoclimate evidence to support their dismissal of ocean acidification.

... Be afraid if you like, but I won't join you. While the paper rather vaguely and timidly suggests that there may be danger in rapid changes of pH, the fact remains that corals, many shellfish, and giant ammonoids evolved in the Cambrian Period when CO2 concentration was many times -- in some cases over a hundred times -- what it is today. Correction: CO2 levels in the Cambrian are estimated to be well over 10 times what they are now. Not a hundred or hundreds. Still, we've had only a rise in recent times of roughly 14%... nowhere near 1250% (from 400 to 5000 ppm). [Jane Q. Public, 2015-06-04]

Jane's telepathy fails once again, because I'm not asking Jane to join in feelings which he might be projecting. I'm just asking Jane to stop spreading misinformation. For instance, Honisch et al. 2012 "rather vaguely and timidly suggests" that "Although similarities exist, no past event perfectly parallels future projections in terms of disrupting the balance of ocean carbonate chemistry—a consequence of the unprecedented rapidity of CO2 release currently taking place."

Once again, the rate of pH change is more important than the absolute pH change, because adaptation via migration and evolution is rate limited. That's why I suggested these papers the last time Jane drew mistaken conclusions from the absolute change in atmospheric CO2 rather than its rate of increase:

Payne and Clapham 2012: End-Permian Mass Extinction in the Oceans: An Ancient Analog for the Twenty-First Century?

"The greatest loss of biodiversity in the history of animal life occurred at the end of the Permian Period (~252 million years ago). This biotic catastrophe coincided with an interval of widespread ocean anoxia and the eruption of one of Earth's largest continental flood basalt provinces, the Siberian Traps. Volatile release from basaltic magma and sedimentary strata during emplacement of the Siberian Traps can account for most end-Permian paleontological and geochemical observations. Climate change and, perhaps, destruction of the ozone layer can explain extinctions on land, whereas changes in ocean oxygen levels, CO2, pH, and temperature can account for extinction selectivity across marine animals. These emerging insights from geology, geochemistry, and paleobiology suggest that the end-Permian extinction may serve as an important ancient analog for twenty-first century oceans."

Kiessling and Simpson 2010: On the potential for ocean acidification to be a general cause of ancient reef crises

"Anthropogenic rise in the carbon dioxide concentration in the atmosphere leads to global warming and acidification of the oceans. Ocean acidification (OA) is harmful to many organisms but especially to those that build massive skeletons of calcium carbonate, such as reef corals. Here, we test the recent suggestion that OA leads not only to declining calcification of reef corals and reduced growth rates of reefs but may also have been a trigger of ancient reef crises and mass extinctions in the sea. We analyse the fossil record of biogenic reefs and marine organisms to (1) assess the timing and intensity of ancient reef crises, (2) check which reef crises were concurrent with inferred pulses of carbon dioxide concentrations and (3) evaluate the correlation between reef crises and mass extinctions and their selectivity in terms of inferred physiological buffering. We conclude that four of five global metazoan reef crises in the last 500 Myr were probably at least partially governed by OA and rapid global warming. However, only two of the big five mass extinctions show geological evidence of OA."

That PETM paper is also worth reading, even if you just skip to the pictures of fossilized leaves with insect teeth marks. Again, it has nothing to do with ocean acidification. Sharply increased insect herbivory during the Paleocene–Eocene Thermal Maximum

"The Paleocene–Eocene Thermal Maximum (PETM, 55.8 Ma), an abrupt global warming event linked to a transient increase in pCO2, was comparable in rate and magnitude to modern anthropogenic climate change. Here we use plant fossils from the Bighorn Basin of Wyoming to document the combined effects of temperature and pCO2 on insect herbivory. We examined 5,062 fossil leaves from five sites positioned before, during, and after the PETM (59–55.2 Ma). The amount and diversity of insect damage on angiosperm leaves, as well as the relative abundance of specialized damage, correlate with rising and falling temperature. All reach distinct maxima during the PETM, and every PETM plant species is extensively damaged and colonized by specialized herbivores. Our study suggests that increased insect herbivory is likely to be a net long-term effect of anthropogenic pCO2 increase and warming temperatures."

Since human agriculture competes with insects and roughly a billion humans depend on seafood, this suggests our unprecedentedly rapid CO2 emissions are causing more than zero damage. And it seems like over a dozen national science academies agree that our rapid CO2 emissions are causing more than zero damage, because they've said with one voice that "the need for urgent action to address climate change is now indisputable".

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