Air Repair via ways of least cost, waste, disruption and uncertainty.

1) The least possible cost is negative; carbon removal that is profitable independent of the carbon removed.

2) The least disruptive carbon removal methods may already escape notice.

3) The least uncertain technologies already exist and work now.

4) The least wasteful methods waste nothing while reducing earlier existing waste.

Hence let’s consider existing, profitable, efficiency-enhancing yet unnoticed carbon removal methods.

Reducing atmospheric carbon inevitably takes energy. Indeed, in storing energy, life reduced carbon, and in getting some of that energy back, we humans are oxidizing carbon.

The least disruptive energy source may well be existing sunlight already hitting earth, yet not inducing photosynthesizing much.

Two large regions now catching sunlight that don’t photosynthesize much are deserts and High-Nutrient-Low-Chlorophyll (HNLC) ocean regions.

Supply of limiting nutrients can allow greater productivity, where and when other nutrients supplied can not.

Provision of limiting nutrients to plants and/or plankton may be the greatest photo-productivity increase opportunity worldwide.

Deserts are dry due to climate. HNLC regions are unproductive due to oddities of water chemistry in oxygen-rich environs.

Deserts cover 10% of earth’s dry land, while HNLC waters stretch across 1/5th of the oceans, Dry land covers nearly 30% of earth, while water covers about 70%.

10% of 30% is 3%; 20% of 70% is 14%, 4.8-fold more, hence, opportunities for engaging sunlight energy in carbon reduction in HNLC waters may exceed those in deserts.

Are there existing unnoticed profitable activities that increase photosynthesis in HNLC waters?

Phytoplankton in HNLC waters typically photosynthesize so little because low iron levels limit their conversion of sunlight in three ways:

1) Low iron directly constrains photosynthesis, since iron irreplaceably catalyzes photosynthesis in multiple ways.

2) Ongoing iron additions to HNLC waters are tiny.

3) Iron rapidly precipitates out of oxygen-rich waters, due to surprising oddities of chemistry.

What existing profitable activity brings iron to HNLC waters without notice?

1) On the Georges Bank, a once-rich fishing region, fully 4% of these water’s iron content came to Georges Bank every year as trace iron in fishing fleet engine fuel, according to

https://mitpress.mit.edu/books/georges-bank.

2) Energy output is the driving objective of fuel consumption.

3) Iron in fuel additives catalyzes more complete oxidation of fuel carbon, reducing soot while increasing energy output, in matching counterpoint to iron's catalysis of carbon reduction in photosynthesis.

4) Some iron picrate fuel additives have proven profitable by increasing energy output of marine engines.

5) FPC is a prominent iron picrate fuel additive company worldwide.

https://www.fpc1.com.

6) The world’s shipping fleet burns about 300 million tons of fuel oil each year.

7) FPC’s current fuel additive treatment levels, of 50 ppb Fe, optimize individual ship owner profitability.

8) The Redfield ratio describes marine life’s ratio of use of sea nutrients, and predicts which nutrient’s low levels will limit sea life growth. It addresses carbon, nitrogen and phosphorus. Sea life uses C:N:P in the ratio of 106:16:1. The original Redfield ratio has been extended to describe another limiting nutrient, namely iron, after the discovery of iron’s importance in limiting sea life. The extended Redfield ratio is still under exploration, and is estimated to be C:N:P:Fe = 106:16:1:~0.001.

9) If 300 millions tons of marine fuel oil were treated with 50 ppb iron, and a fifth of this iron fell on HNLC waters, catalyzing photo-productivity, (at an extended Redfield ratio of C:N:P:Fe = 106:16:1:0.001), this iron would induce 1.5 million tons of carbon removal from air via HNLC waters’ increased photosynthesis.

Perhaps marine fuel can be treated with higher levels of iron, to optimize, not ship owner profitability, but global carbon removal.

1) The upper acceptable limit on treated fuel’s iron content may be maintaining existing fuel ash levels in tests at about 0.01%, or 100 ppm,.

2) Increasing fuel iron content via treatment to 50 ppm, instead of 50 ppb, might increase carbon removal in HNLC waters 1,000-fold, while perhaps negligibly affecting fuel ash content.

3) Expanding fuel treatment at these higher levels to the entire worldwide shipping fleet’s fuel usage of ~300 million tons fuel oil per year might increase carbon dioxide removal in HNLC waters to 5,500 million tons; carbon removal there to 1,500 million tons, to ~4% of annual human carbon release, and to more than the current carbon release of the entire worldwide shipping fleet’s fuel usage.

1) Mapped here are shipping densities worldwide.

(http://nicolasrapp.com/shop/wp-content/uploads/2014/10/F21CHAv2-1.jpg)

 

2) “HNLC conditions occur in remote, offshore areas of the

subarctic north Pacific, subtropical equatorial Pacific, and Southern Ocean...” EldridgeML 2004: 19

3) Much shipping crosses to and from Asia and North America via‘Great Circle’ routes, between Asian manufacturing and USA consumers. Perhaps this shipping traverses the subarctic North Pacific.

4) Perhaps FPC targeting those ships traversing subarctic North Pacific waters for fuel treatment at the higher 50 ppm level would restore much carbon fixation/reduction while using existing infrastructure in profitable ways.