Just over 90 years ago a discovery was made that started a fascinating journey exploring human evolution in Africa. The Broken Hill skull was the first early human fossil to be found in Africa and evidence suggests it probably represents the species that we, Homo sapiens, descended from.

http://phys.org/news/2013-03-early-human-fossil-africa-debut.html#jCp

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First early human fossil found in Africa makes debut

Phys.org

Interesting article.  We should not underestimate advances in CO2 sequestration, or modest increases in nuclear and hydroelectric power.  I'm more optimistic about renewable energies growth in the coming decades than the authors however (think computer revolution over the last 30 years; very similar science and technology are involved).  Add to this improvements in energy efficiency (as has been happening steadily for decades), substitution of natural gas (with sequestration) for coal, and there is yet more cause for optimism.  If we can meet a goal of keeping CO2 levels =< 500 PPM, a 1 - 1.5 temperature rise is within possibility.

I can't agree with Figure II's details.  GW will not only shift the temperature curve, but should broaden it as well.  This means extreme warm events will increase and the opposite decrease, but there will still be plenty (and more, albeit) of both.

Oh, please don't use pictures of cooling towers emitting plumes of steam.  That has nothing to do with CO2 or warming (even ST plants have them), and can only confuse people.  And phrases like,  "global meltdown"  really are misleading

Interesting article.  We should not underestimate advances in CO2 sequestration, or modest increases in nuclear and hydroelectric power.  I'm more optimistic about renewable energies growth in the coming decades than the authors however (think computer revolution over the last 30 years; very similar science and technology are involved).  Add to this improvements in energy efficiency (as has been happening steadily for decades), substitution of natural gas (with sequestration) for coal, and there is yet more cause for optimism.  If we can meet a goal of keeping CO2 levels =< 500 PPM, a 1 - 1.5 temperature rise is within possibility.

I can't agree with Figure II's details.  GW will not only shift the temperature curve, but should broaden it as well.  This means extreme warm events will increase and the opposite decrease, but there will still be plenty (and more, albeit) of both.

Oh, please don't use pictures of cooling towers emitting plumes of steam.  That has nothing to do with CO2 or warming (even ST plants have them), and can only confuse people.  And phrases like,  "global meltdown"  really are misleading

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Ron Dobbs originally shared:

 

http://www.extremetech.com/extreme/185336-carbon-neutrality-has-failed-now-our-only-way-out-of-global-warming-is-to-go-carbon-negative

Comments such as "global warming is adding four million Hiroshima bombs to the globe everyday" are so absurd they should deserve no comment.  But it's apparently necessary.  Contemplate how much total heat the atmosphere possesses; enough to rise it from -273C (absolute zero if there were no sun) to ~15C average today. That's 288 total degrees for the entire atmosphere, or (I'm neglecting phase changes, which add more energy to the equation).  Now, the addition of (0.8C/century)/(century/100 years)(year/365 days) = 2.192e-5C/day of the total atmospheric energy added to the planet every day.  If that's 4 million atomic bombs, then those four million (Hiroshima sized) bombs increases the atmosphere's energy only by 0.002192% each day.  Of course if a day is unusually hot, say 10C hotter, then that is (10.00/2.192e-5C) X 4 million bombs = 1.8 trillion Hiroshima bombs to produce that extra heat (far, far, far larger than the entire Earth's nuclear arsenals).  And that is nothing compared the heat of the whole atmosphere.

It's just a scare mechanism.  And putting it terms of nuclear weapons (which it has nothing to do with) just nails in the terror.  And worse, if anything, it has the opposite effect.  Global warming and climate change should be talked about -- to the public -- soberly, responsibly, and with as much scientific explanation as the public can handle.  The doubts and problems should be admitted.  PR campaigns, falsehoods, one-sided presentations, exaggerations, and ads like the above will only be seen as they are, leading to further resistance.

Climate myths: CO2 isn't the most important greenhouse gas

17:00 16 May 2007 by David L Chandler

"Water is a major greenhouse gas too, but its level in the atmosphere depends on temperature. Excess water vapour rains out in days. Excess C...O2 accumulates, warming the atmosphere, which raises water vapour levels and causes further warming.

"Is water a far more important a greenhouse gas than carbon dioxide, as some claim? It is not surprising that there is a lot of confusion about this - the answer is far from simple.

"Firstly, there is the greenhouse effect, and then there is global warming. The greenhouse effect is caused by certain gases (and clouds) absorbing and re-emitting the infrared radiating from Earth's surface. It currently keeps our planet 20°C to 30°C warmer than it would be otherwise. Global warming is the rise in temperatures caused by an increase in the levels of greenhouse gases due to human activity.

"Water vapour is by far the most important contributor to the greenhouse effect. Pinning down its precise contribution is tricky, not least because the absorption spectra of different greenhouse gases overlap.

"At some of these overlaps, the atmosphere already absorbs 100% of radiation, meaning that adding more greenhouse gases cannot increase absorption at these specific frequencies. For other frequencies, only a small proportion is currently absorbed, so higher levels of greenhouse gases do make a difference."

DJS -- I have attached a chart showing these overlapping and separate regions. Green is water vapor and red carbon dioxide. Although there is a lot of overlaps there are still distinct regions where they absorb in different parts of the spectrum. I also have to correct a miscalculation I made. A 1.0 degree C increase in atmospheric temperature should result in a seven percent increase in water vapor; i.e., an increase in ~1500 ppm (the CO2 increase is ~100 ppm). Although pure CO2 appears to have ~20 times the greenhouse effect than pure H2O, the overlaps in saturated regions (all IR blocked) appears to make the contribution of both approximately the same. There is also still some natural warming, which, as I read the 2013 IPCC data, is between 25-50% of the total. -- END DJS

"So why aren't climate scientists a lot more worried about water vapour than about CO2? The answer has to do with how long greenhouse gases persist in the atmosphere. For water, the average is just a few days.

This rapid turnover means that even if human activity was directly adding or removing significant amounts of water vapour (it isn't), there would be no slow build-up of water vapour as is happening with CO2"

 

An Explanation of Ocean Acidification and its Effects on Life

By David J Strumfels on http://AMedelyofPotpourri.Blogspot.com/

 

 

 

 

 

 

 

 

 

(Wikipedia, 2/28/14):  "Between 1751 and 1994 surface ocean pH is estimated to have decreased from approximately 8.25 to 8.14 (how measured in 1751?),[5] representing an increase of almost 30% in H⁺ ion concentration in the world's oceans.[6][7] Available Earth System Models project that within the last decade ocean pH exceeded historical analogs [8] and in combination with other ocean biogeochemical changes could undermine the functioning of marine ecosystems and many ocean goods and services.[9]"

8.25 to 8.14 -- what does that mean?  What it does not mean is that the oceans are acidic, for their pH would have to be below 7.0 to say that.  In fact, we would call it alkaline (the opposite of acidity).  But acidification indicates a direction, not a specific place on the pH scale (some climate warming skeptics seem not to understand the difference) .  Chemically, pH is defined as the "negative log (hydrogen ion concentration)". But what does THAT mean?

The hydrogen ion, or H⁺ (a hydrogen atom without its electron, or a bare proton), is the main acidic species in water.  If the concentration of H⁺ is 8.00E-8 = 0.00000001 Molar (moles per liter, or just M), then the log of that number is -8.00, its negative log is 8.00, and so the pH is 8.00.  As to the specific cases here:  pH 8.25 => -8.25; antilog (-8.25), or 10 to the power of the number) yields 5.62E-9 H⁺ M, while 8.16 => -8.16 => 7.14E-9 H⁺ M.  That's a difference of 1.52E-9 H⁺ M concentration, or 0.00000000152M.  Yes, it is a 29% increase in acidity, mathematically.  Of course, 29% of practically nothing is even closer to actually nothing.   But chemically, especially biochemically, it can be very important.

For example, your blood pH has to be kept within a narrow range of 8.25 and 8.35, or illness, even death, can result.  I do not know all the reasons for this, but I can tell you that many biomolecules have both basic (opposite of acidic) and acidic forms, and they are chemically different.  They may have to be kept within a very narrow equilibrium of basic and acidic forms, each running a different reaction.  Or some are all necessarily basic at this pH, while others all acidic.  At pHs near 7.0 (neutrality), these equilibria are extremely sensitive to these tiny changes I outlined above.

So it is not difficult to see how a drop in 0.09 pH units (combined with a degree or two warming) could wreak havoc on numerous sea organisms, plant, animal, protozoan, or bacterial. On the other hand, the immensity of the oceans assures that there will be pH (and temperature) variations, in time and location, so sea life should be expected to be a little more hardy. But there are still fairly strict limits. The 21'st century will surely test those limits.

A little more chemistry now. We blithely speak of CO₂ increasing water acidity, but how? First, CO₂ is mildly soluble in water, the lower the water temperature, or the higher the water pressure, the more soluble (for thermodynamic reasons we need go into here) it is. That isn't enough for acidity, however. There has to be a chemical reaction between CO₂ and H₂O first: CO₂ + H₂O <=> HCO₃^- and H⁺. The <=> sign means the reaction goes in both directions; which set of reactants/products is favored depends on various conditions. Cold leans toward the first two, pressure the opposite way. This again is thermodynamics, with enthalpy and entropy competing against each other. At the low concentrations of CO₂, in general the latter is favored. But it's still a tiny contribution of H⁺, enough, as you've seen, to lower ocean water an average of 0.1 pH units over the last two hundred years (and I would not be surprised if 0.5 – 0.7 units of that is within the last 30-40 years, and it ~doubles by 2100 – this is serious).

High Octane Fuels and the Use of Ethanol in Engine Fuels

You've seen and heard the word octane with relation to cars and gasoline all your life.  Well, unless you never pumped gasoline into your car.  Ever wonder what it means?  Well, the basic answer is, the higher the octane number the more smoothly the gasoline will burn in you engine, reducing any "knocking" and increasing efficiency and mpg.

But that still doesn't tell us much.  Where does this number come from, how is it determined, and what chemical and physical properties of the fuel control the final rating?

 

A little chemistry is needed to explain this.

 

Octane rating is measured relative to a mixture of 2,2,4-trimethylpentane, CH3-C(CH3)2-CH2-CH(CH3)-CH3(an isomer of octane; it has eight carbons) and n-heptane (7 carbons in a straight line).

Arbitrarily but unsurprisingly, the octane is given an octane number of 100, while the heptane is assigned 0.  Mixtures of the two are then used in engine to access their different octane numbers.  Incidentally, there are hydrocarbons with octane numbers (not to be confused with octane numbers compounds!) higher than 100, for jet and rocket fuels (which of course cannot be allowed to knock or fail).

 

You're probably asking at this point:  why not just give me pure 2,2,4-trimethylpentane at the gas pump and "put a tiger in my tank?"  Well, they could, but there'll be another tiger in your bank account as it would be horribly expensive.  Why?  Now, finally, we get to petroleum, oil, that is pumped out of the ground.  Petroleum is not one compound; it is instead a mixture of many, many different chemicals.  The cheapest way to separate them is by "fractional" distillation, which is rather like a much more complicated and expensive kind of distillation than used to turn wine into cognac, or mash into beer or whiskey, or just to extract straight ethanol.

 

So, trying to fractionate pure 2,2,4-trimethylpentane, or any pure chemical, out of crude petroleum is so expensive that only a professional race driver could afford it, if they wanted to -- they actually use other, better, fuels.  It is far easier and cheaper to just take an entire fraction of the distillation process and use that as gasoline.  Now we come to problem two, the big problem.  This fraction, untreated, will not perform well in gasoline engines because its octane number is simply not up there enough; certainly not the 86 of the standard gasoline you buy at the pump.  So -- what might we add to the fraction to get its octane number up to 86, or 89, or 91-93 (pump standards)?

The standard method for boosting octane is to add an additive.  The first additive (that I know of) was tetraethyl lead.  Because of its spherical shape, this compound was very effect.  It did have a serious downside however.  Burning it in a car engine spewed lead and lead compounds into the atmosphere, where it could be inhaled/absorbed into bodies and do real damage there -- rather like mercuric compounds.  Thus, tetraethyl lead was gradually phased out, and the search for a safer additive was undertaken.  The first(?) of these was methyl tert-ethyl ether, or methyl - O - C(Me)3.  Like tetraethyl lead it also it is also highly spherical, making it an excellent octane booster.  Unfortunately, it ran into another problem.  It tended to seep into groundwater from tanks, poisoning water supplies.  So it too, in the end was phased out.

Nowadays we mix up to 10% corn-ethanol (drinking alcohol) into gasoline to improve its anti-knock properties.  A second reason is that, ethanol being derived from atmospheric carbon dioxide, doesn't increase the level of this important greenhouse gas, thus helping to fight anthropogenic climate warming.  Many environmentalists was to increase it to 15% -- but there are negatives to it to that cause others to rid it altogether is gasoline.  The problem is gasoline containing ethanol is especially subject to absorbing atmospheric moisture, then forming gums, solids, or two phases (a hydrocarbon phase floating on top of a water-alcohol phase), all of which shorten the lives of engines.  This is why ethanol is still not the perfect additive.  It also takes a great quantity of land to grow a sufficient quantity of corn, which drives it and other vegetables up in price.

I claim no knowledge of what a perfect additive would be.  Perhaps we will have migrated from natural gasoline to syn-fuel mixtures derived from algae/plants first, via genetic engineering (as we already are), if that is, electricity and hydrogen/LNG don't get there first.