The Problem with Biokinetic Sequestration

Writing in the current (6 July 2009) edition of Peak Oil Review, James W. Bunger, PhD asserts, "Peak OIl May Solve the Climate Change Problem without Regulation."

He contends that there is no need to regulate carbon dioxide emissions using cap and trade schemes like those found in the Waxman-Markey Bill (HR 2454) because two natural force are at work: rapidly approaching limitations on fossil fuel availability and natural (biokinetic) sequestration. He writes...

Intuitively, anyone who recognizes the practical limitations on fossil energy supply knows emissions will not rise exponentially for another century, as portrayed by the IPCC and the US Global Climate Change Research Program (ref-1). The forecast growth rate in energy consumption—1.4% per year—is not very large, but compounded over a century it would suggest that by 2100 we would be consuming three times more energy than we consume today. In the meantime, we will have consumed about 15 trillion barrels-of-oil-equivalent.

That is an astounding number considering we only have about 13 trillion barrels-equivalent in oil, gas, coal, oil sands, heavy oil and oil shale combined. And only a portion of this total, perhaps no more than one-third, can ultimately be recovered under reasonable economic conditions.

"A second is the systematic underreporting of the beneficial impact higher CO2 concentrations have on photosynthesis," he writes, noting that plants and the oceans can absorb much of the CO2 released by the last two hundred years of industrialization.

"In 2008 we emitted about 34.2 billion tonne [of CO2], of which 18.8 billion went missing. A prime suspect for this missing mass is the fertilization effect that CO2 has on photosynthesis rates."

Dr. Bunger developed a biokinetic model that takes into the account the rate of natural plant and ocean sequestration and projections on oil, gas and coal depletion (Colin Campbell, Energy Watch Group 2007 Coal Report ). The result of that model, shown below, indicates that CO2 emissions will level off well below the 450 ppm tipping point suggested by James Hansen and others around 2030 and begin a gradual decline.

He concludes, "Rather than making the problem worse through regulation, political effort should be better spent on improving efficiency of energy use, and helping to ensure we have adequate domestic supply of fuels when the world-wide competition for dwindling supply begins in earnest. That time is not long from now."

What About Ocean Acidification?
While Dr. Bunger's model sounds encouraging, assuming a world with less and less fossil energy at its disposal will be a peaceful one that has transitioned to more sustainable lifestyles, there is one glaring omission in his paper: ocean acidification. This is the process by which increasing amounts of carbon dioxide gradually lower the pH balance of the oceans, making it more acidic. UNESCO's Ocean Acidification Network explains the process and its consequences thus:

When CO2 dissolves in seawater, it forms carbonic acid, which releases hydrogen ions into solution. Acidity is a measure of the hydrogen ion concentration in the water, where an increase in hydrogen leads to an increase in acidity (and a decrease in the pH scale used to quantify acidity). These hydrogen ions then combine with carbonate ions in the water to form bicarbonate. Carbonate ions are the basic building blocks for the shells of many marine organisms. Thus the formation of bicarbonate through this chemical reaction removes carbonate ions from the water, making them less available for use by organisms. The combination of increased acidity and decreased carbonate concentration has implications for many functions of marine organisms, many of which we do not yet fully understand.

While these pH levels are not alarming in themselves, the rate of change is cause for concern. To the best of our knowledge, the ocean has never experienced such a rapid acidification. By the end of this century, if concentrations of CO2 continue to rise exponentially, we may expect to see changes in pH that are three times greater and 100 times faster than those experienced during the transitions from glacial to interglacial periods. Such large changes in ocean pH have probably not been experienced on the planet for the past 21 million years.

As the tryptysh NOAA photographs at the top of the page indicate, ocean warming and acidification can have a profound impact on marine ecosystems. As recently as 2008, NOAA researchers discovered evidence that the acidification is now taking place on America's continental shelf as close as 4 miles off shore of northern California, but extending from Canada to Baja Mexico.

Explained NOAA oceanographer Richard A. Feely, “Our findings represent the first evidence that a large section of the North American continental shelf is seasonally impacted by ocean acidification,” said Feely. “This means that ocean acidification may be seriously impacting marine life on our continental shelf right now.”

Burke Hales, with Oregon State University College of Oceanic and Atmospheric Sciences, adds...

We don't know how this will affect species living in the zone below the level of the lowest tides, out to the edge of the continental shelf," said  Ianson, an oceanographer. "We do know that organisms like corals or pteropods are affected by water saturated with CO2. The impacts on other species, such as shellfish and other juvenile fish that have economic significance, are not yet fully understood."