Monday, January 16, 2012

More "Ice Ages" In the Distant Future? Don't Believe It!

Figuring out climate science is not an easy task, and often requires plenty of devotion, including to historical records, as well as climate physics, solar physics and ....plain old regular physics. This is often more than most lay folks or press pundits are willing to commit to so it's no surprise that so much bollocks can be written which gets attention either in a comatose corporate media or on some blogs.

Much more difficult to parse or grasp is how any academic worth his or her salt could seriously believe that another Ice Age could be on its way.....even over a thousand years hence! Yet in his Jan. 14-15 column in the WSJ ('Are We Holding A New Ice Age at Bay?'), Matt Ridley cites a paper published by university reearchers in Cambridge, London and Florida, claiming that while current greenhouse emissions may temporarily avert an Ice Age, we will still expect to see one "within about 1,500 years".

I don't think so!

Their argument is that our current "inter-glacial" (I refer to it as the first era of the "no more glacial") echoes the patterns of a previous warming period about 780,000 years ago. Like other Ice Age claimants, they make the mistake of believing that the Earth's orbit will somehow change and its eccentricity, axial tilt or both will over compensate for the CO2 accumulated and produce a new glacial period.

They fail to grasp that the change in gravitational potential energy (V = - GM/r) required to alter the Earth's orbit even a minuscule amount is stupendous - as even simple calculations would disclose. To get a magnitude of change sufficient for triggering major climatic impact you're talking about changes of the orbital elements in the range of 2- 5%. This is totally preposterous, given solar system energy constraints, and why most astronomers dismiss Milankovitch.

The alteration of the Earth's axial tilt is equally formidable to effect. For a theoretical change in obliquity, say from 21 to 24 degrees one can work out the change in angular momentum that’s required:


L = w I_p (ñ + cos ^2 (Θ)]

where w is the radial velocity, I_p the polar moment of inertia, ñ a direction in space and Θ the angle from vertical. Then d L = w Ip ( cos ^2 (Θ2) – cos ^2 (Θ1)] since we do not expect the magnitude of either w or I_p to change.

Then if Θ2 = 24 deg (= 0.419 rad), and Θ1 = 21 deg (= 0.367 rad):

Using I_p = 0.3307M r^2 =

I_p = 0.3307 (6.0 x 10^ 24 kg) (6.378 x 10^6 m)^2

I_ p = 8.07 x 10^ 37 kg- m^2 (polar moment in appropriate units)

dL = {7.272 x 10^ -5 rad/s) (8.07 x 10^ 37 kg- m^2 ) x ( cos ^2 (Θ2) - cos^2 (Θ1)]

dL= (5.87 x 10^33 kg-m2 s-1) (0.871 - 0.834) = 2.17 x 10^ 32 kg-m2/s

This is an enormous change in angular momentum of the planet – even given a presumed 41,000 year period to accomplish it. WHERE is the external force coming from to effect this change in angular momentum? We don’t know – since neither the Milankovitchies or their apologists and academic invokers never say. All they have is an empirical correlation schema – as opposed to a bona fide theory with self-consistent explanatory power and predicted orbital parameters, for the changes postulated.

Thus, we need to know – before “time expires” – where all the external torque is coming from to alter the Earth’s angular momentum by such a vast amount! Even allowing for the length of time- the magnitude of angular momentum must be accounted for. It has to come from somewhere, it simply cannot materialize in vacuo.

So if orbital changes are out, what IS the cause of the Ice Ages we've experienced? Basically, the CO2 concentration! Never has an Ice Age occurred when this is above 200 ppm, and never has an interglacial lasted very long when the CO2 concentration is less than 200 ppm. It now stands at nearly 380 ppm, and we believe the threshold to trigger the runaway greenhouse effect will kcick in between 480- 500 ppm.

Now, an added fact is that we are adding CO2 at the rate of 2 ppm/ year and the insolation is increasing at 2 watts/yr. A more disturbing fact is that CO2 also accumulates because earlier depositions remain even as new burdens are added yearly! Thus, the CO2 warming we’re now experiencing is not the result of just one year – but 100 years’ accumulation. In effect, each year we not only deal with the immediate concentrations of CO2 produced but also cumulative concentrations added from 100 years ago.

The process may be described something like a series with terms being added, viz: to describe the CO2 content added up to now in the atmosphere (CO2 depositions added by the completion of year 2011), we must initiate the series with n= 1 (e.g. for 1912), viz. CO2( 2011) = x_1 + x_2 + x_3 + x_4 +.............+ x_100

E.g. terminating at the last term, 100 years later. Here each ‘x’ denotes the CO2 burden added for each year in succession.Thus, the CO2 effect for a given year is not just for that year, but rather inclusive of the cumulative additions for all the years - starting up to 100 years before!

This means, all other things being equal, at any given time we have at least 100 years worth of CO2 concentrations to ADD, as well as the infrared energy component in watts. So, we can safely say - unless human cease using all fossil fuels immediately - that by the year 2112 we will have added another 200 ppm in CO2 concentration to the 200 ppm yearly real time additions, and also added 200 watts to the solar insolation or heat effect of it (estimated now at 1370 w/m^2). That means the latter will be expected to rise to 1770 w/m^2 while the CO2 concentration will reach 380 ppm + 400 ppm = 780 ppm. In other words, we will already have not only reached but surpassed runaway greenhouse conditions.

But it gets even worse!

An article appearing in Eos Transactions of the American Geophysical Union (Vol. 83, No. 34), August 20, 2002, ‘Progress Made in Study of Ocean’s Calcium Carbonate Budget’, noted that sedimentary carbonates represent the largest reservoir of carbon on Earth. The author also noted that “a third of the anthropogenic CO2 that has been added to the atmosphere since the middle of the 18th century has been absorbed by the oceans. " This means that the oceans, acting as CO2 reservoirs, have actually masked the worst effects of global warming and that when their saturation point is reached, the spillover effect will be rapid and calamitous indeed.

Well, as the CO2 concentrations exceed 500 ppm, that threshold will be reached! In other words, like by the year 2060. Increases of atmospheric CO2 also increase concentrations of inorganic carbon, mainly in the forms pCO2 and HCO3. A side effect is to also diminish the pH of sea water. The author notes p. 374:

Future decreases in sea water pH (and CO3(-2)) concentration will decrease the saturation state of the waters with respect to Ca CO3”.

This means that spillover becomes much more likely as the saturation threshold is lowered, with masses of CO2 released additionally into the atmosphere. Melting ice from glaciers, etc. – far from being an assisting agent to a new ice age, will reduce further the sea water pH and accelerate the release of CO2 from the oceans. Leading to much much warmer conditions and even more acidic oceans than exist currently (likely pH of 6 or less by 2075).

Indeed, we have excellent research showing that once CO2 levels reach 1 ½ times or more their current concentration - resulting in mean temperatures up to 10 degrees Celsius higher- there'll be NO way to halt the warming process. (See: Kerr, R.: No Way To Cool The Ultimate Greenhouse, in SCIENCE, Vol. 262 (October 29, 1993, p.648.)

Let's get it straight that once that runaway greenhouse sets in, it's game over - and there will be absolutely NO chance of any Ice Age recurring.

More amusing than the academics' take of "a new Ice Age in 1,500 years" is the ultimate irony that all of humanity will be dead long before that time, since all the oceans will have long since reached their latent heat of vaporization. Those highly acidic oceans from which life would have vanished even decades earlier will now be mere memories. And Earth?.....It will have mutated into Venus II.

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