Paradise to Ice

There are Edens on earth today. They are not found toward the North and South Poles today, but for most of earth history they were.  What causes the planet to transition from paradise to ice? This is a matter of considerable interest to naked apes.

We live in an ice age. Fortunately, we are towards the end of a warm fibrillation within our ice age, but we have ice at both poles. In Paradise there was no ice at all.

A lot off of effort has gone into figuring out the fibrillations within our ice ages. Slight orbital changes certainly have an influence on fibrillations, but no known orbital changes are long enough to explain ~200 million year paradises between episodes of ice.

It is often suggested that changes in the position of continents govern paradise. In particular,  that the separation of South America and Antarctica, allowing a powerful vortex of wind and ocean currents around Antarctica, set the stage for the ice age we live in.

While this is certainly an important influence, we will show that in prior transitions from paradise to ice, the continents prevented a South Polar Vortex.  The plate tectonic reconstructions in the header image and below are by by C.R. Scotese, PALEOMAP Project.

Above is the configuration of continents during the Carboniferous ice age. The colors show the motion: magenta 340 mya, tan 320 mya, grey 300 mya. Conditions at the North Pole are unchanged, and  a South Polar vortex was impossible.

Here is a similar map for the Ordovician ice age. The green is 460 mya and the magenta 440 mya. The configuration is weird in this projection.

A South Polar view above is better. Once again, a large landmass between 40 and 60 degrees south blocks any Antarctic vortex.

There were a couple of ice ages in the Proterozoic. The continental positions are sketchy three quarters of a billion years ago, but there are considered to be two near “snowball” episodes about 100 million years apart with the continents looking something like this.

The little green squares are “tillites”, glacial moraine deposits. Some are near the equator.

This configuration favors a Panthalassic “meridional overturning” circulation, but not a vortex at either pole.

My intuition is that all the transitions from paradise to ice had a similar cause. Just my intuition. It is conceivable that they all had different causes.

We can say with certainty that if they all had different causes, only one out of five resulted from a polar vortex.

 

 

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Posted in Climate, Paleoclimate, Paleogeography | 4 Comments

The Missing 13C

A couple years back we decided to try making an isotope integrated Carbon cycle model, to see if we could replicate the isotopic “excursions” evident in the geological record. This effort foundered because we couldn’t even balance the current Carbon cycle when we integrated isotopes.

The problem is that the per mil 13C PDB of atmospheric Carbon (-8), is probably the best measured and least uncertain value in the entire Carbon cycle. Yet this value is unsustainable and would drop like a rock when the best estimates of the isotopic fluxes in and out of the atmosphere are used.

Basically, the atmosphere needs more 13C. An additional input 60 GtC at +5 PDB per year to get a reasonable approximation of the -.02 PDB measured yearly decrease.

A lot of people (including me) suspect that the estimates of yearly volcanic Carbon output is low. The current estimate is .1 GtC yearly, and is ignored in the model as insignificant. This would seem an attractive place to look for the missing 13C. One might suspect that volcanic Carbon might be above the Pee Dee Belemnite (PDB) baseline. Positive numbers mean more 13C, and negative numbers less 13C than the standard.

Unfortunately, data from the Encyclopedia of Volcanoes below indicate that volcanic Carbon is predominantly negative.

Volcanic d13C credit Encyclopedia of Volcanoes.png

Adding more volcanic carbon will make the problem of stabilizing atmospheric 13C content even more difficult.

Aggregated First Year Delta 13C Per Mil Atmospheric Inputs
-0.47315 Deep Ocean
-2.08708 Mixed Lay
3.797101 Vegetation
-0.01217 Swamp
-0.00464 Plankton
-1.02431 Soil
-0.20601 Humans
-0.01025 Total (-.16 measured)

It can be seen that only the interaction with vegetation results in increased atmospheric 13C. Seemingly, this is where we must look for the missing 13C.

Either plants are absorbing more CO2 than we think, or they are respiring more than we think, or both. The run above achieves a rough balance by supposing that plants are respiring more than we think. This approach is attractive, because if plants are only absorbing more, there would be a large increase in plant biomass. Measurements indicate that plant biomass expressed as Carbon (about half of plant dry mass) is increasing about .4 GtC per year. It would take about 20 GtC/yr of increased absorption (alone) by plants to achieve a similar balance. This would result in about fifty times more biomass increase than we measure.

Any accounting for the Carbon isotope values applied to supposed fluxes indicates that current conceptions of the Carbon cycle are incorrect. The well measured isotopic value of the atmosphere would be unstable, and the measured rate of change cannot be replicated without a large additional 13C input, or a large reduction in the 12C input.

We expect the atmospheric mass as Carbon to increase yearly somewhat below the one way inputs of humans and soils, ~70 Gt. Large reductions in 12C inputs would push this mass balance in the wrong direction. The large increase in 13C from increased plant respiration proposed here puts the yearly change in bass balance in the expected range (~61 Gt).

It seems we must look to vegetation for the missing 13C

 

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MODTRAN, The One ppm Exercise

MODTRAN is impressively nuanced sometimes. Ordinarily MODTRAN is used on a macro scale at plausible altitudes and greenhouse gas concentrations, but it definitely resolves at single meters of altitude and single ppm of greenhouse gasses.

Here we explore one ppm CO2 with all the other GHG’s zeroed out. We look both up and down from one meter, and 70 kilometers.

Modtran Up and Down 1 meter 1 ppm ann

Beginning at one meter, we see little difference from the Planck curve looking down. This is no different from what we see at 400 ppm looking down up to about 400 meters altitude, except that there is .31 W/m2 MORE upward radiation at 400 ppm.

Looking up from one meter the reach of a single ppm of CO2 is astonishing. The 667.4 fundamental bend does not quite kiss the downward looking curve, meaning that it is seen radiating from some small distance above one meter. Only the fundamental bend can be seen radiating from essentially the surface to an altitude of about six kilometers.

At the temperature of six kilometers the additional bending vibrations at 647.1 and 688.7 kick in, along with the P and R rotations dependent on the fundamental bend. At a temperature 15 kilometers we see the additional vibration at 618 and the bend to stretch transition at 720.8

Interestingly, at 1 ppm you get almost a “chromatograph” of the relative intensities, with the factor of progressive movement away from top dead center of the Planck curve with increasing altitude omitted.

Modtran up and down 1 ppm 70 km

The view of 1 ppm from 70 kilometers is I’m many ways the inverse of the view from one meter. Looking up from 70 km there is essentially no IR coming down from above. Looking down we see the “effective radiative levels” of the CO2 transitions to space. The fundamental bend at 667.4 is seen radiating at a temperature of 12 km, and once again it shows extraordinary reach, being the only signal from 6 to 12 kilometers.

At 1 ppm, there is essentially no difference in either upward or downward radiation above 25 km elevation.

Just for kicks, below is 1 meter looking up vs 70 km looking down at 1ppm.

One meter looking up vs 70 km looking down

Let’s compare the 1 meter up and down view at 400 ppm.

Looking down, there is no discernable difference from 1 ppm, and the total upward IR flux is only .31 W/m2 more at 400 ppm.

There are lots of differences looking up. The fundamental bend and rotations, and the nearby three order of magnitude weaker transition at 647.1, have melded into a zone radiating at the Plank temperature of the ground (299.7 K). Notably, this is above the temperature seen looking down. The upwelling radiation deviates from the Planck curve more at top dead center than elsewhere along the curve. The downwelling radiation is seen at a higher temperature at the ground BB curve.

The transitions at 618 and 688.7 radiate at about the upwelling (down looking) curve, 597.3 and 720.8 are seen radiating at the temperature of perhaps 800 meters, and a crop of extremely weak transitions is seen radiating above 9 kilometers.

Astonishingly, there is a 60.5 W/m2 increase of downward flux between 1 ppm and 400 ppm, as seen from one meter elevation.

Here is 400 ppm up and down from 70 km.

Up and Down 70 km annotated

We have the usual cast of transitions, but their intensities (and temperatures) change with altitude and CO2 concentration. The difference in upwelling radiation between 1 meter and 70 km is 118.75 W/m2 at 400 ppm.

A transition can be deemed “saturated” when it radiates at a temperature conforming to the Planck curve. At 400 ppm from 70 km, the fundamental bend rotations are radiating at the 220K (12 km) curve, but the 667.4 bend itself reaches back down to a temperature of 9 km.

For kicks again, 1 meter looking up vs 70 km looking down at 400 ppm.

One meter looking up vs 70 km looking down 400 ppm

 

The fundamental bend is saturated looking up from a meter, but not above 9 km in the atmosphere.

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Infinity and Things to Do.

Infinity is meaningless. Everything is nothing.

When you rise every morning, the possibilities are infinite.

The difference between everything and nothing is you.

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Alexa and Chatty Cathy

Chatty Cathy was a doll. You could pull this string on her and she would say something random. She was the first electronic fortune cookie. She could say  maybe a dozen and a half different things. Never anything cogent. Some tangy things to keep your interest, some sweet things to butter you up, but nothing to piss you off by design.

So it is with Alexa. Algorithm rather than string. Marketing to lonely people. A pretense that your voice phonons in a virtual world, in  conversation with a remote server, is real.

Handy, but not real. Handy as a voice activated search engine (there are others). Handy if you want to listen and nobody else wants to talk…

Posted in Human need for Judgdment, Sociology | Leave a comment

The Terribly Tenacious Trough

 

Humans are prone to emotional conclusions like “the weather has gone crazy”. Last year at this time, even with the normal rainfall in the north half of the state, many asserted that California was in “new normal” permanent drought. The far above normal rainfall throughout the state this year shows that this sentiment is clearly wrong, but the same folks who set forth permanent drought will now assert unprecedented “crazy rain”.

We have done a series of posts on the drought in California using data from San Francisco that dates back to 1850. Here we present a look at the same data looking at high rainfall years in the same data set to evaluate how crazy this year really is.

SF Cumulative 2016-17

Perhaps this year’s trough is not so terribly tenacious after all. The season is not over and the tingling in my own bones is that it will be a wet spring, like many I remember from the seventies. Nevertheless, if I were a betting man, I would bet that this year will top out below the five previous years shown. If this season dries out, there will be more years to add above this year.

The point here is that the “ridiculously resilient ridge” that led to four consecutive years of below normal rainfall in California did not produce any individual years of record drought. If the terribly tenacious trough does the same in reverse, where are we?

As we have always been; naked apes staring into the sunrise. Is God punishing us?

If you want to project your guilt onto statistical noise, you go.

I’m going with the data.

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Effective Radiative Level

There is this concept that by averaging all the different radiative spectra that satellites see from earth from very high altitudes an Effective Radiative Level can be derived that has meaning for the radiation balance for the planet.

The basic idea is that the addition of greenhouse gasses, predominantly CO2 by humans, will raise the Effective Radiative Level. The further idea is that this supposed increase in altitude for the radiative level takes place within the part of the atmosphere where there is lapse, i.e. the atmosphere cools with increasing altitude.

The claim is that since a higher altitude implies a cooler temperature, the radiation to space will take place at a lower blackbody temperature with lower energy to the fourth power, and will cool the planet less effectively.

We have developed the tools to evaluate this claim. Rather than a single average level and blackbody temperature, the satellites see substantial differences in radiative altitude across the earth longwave spectrum.

All Down Looking, Planck Bounding

The “effective” radiation seen from space in the earth long wave spectrum ranges about 100K, from a remarkably consistent  220+-7K for the CO2 bands to a wildly different 320K+ in the atmospheric window.

The bottom line is that CO2 has its own radiative channel to space entirely separate from the effective Planck temperature of the atmosphere as a whole. This channel radiates at the tropopause and above where the lapse rate reverses and becomes negative. Rather than radiating at a lower temperature, with increasing concentration and higher radiative altitude, CO2 radiates to space to the fourth power of a higher temperature with increasing concentration.

 

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