Forty years ago carbon was not a topic in casual conversation. Farmers, however, always knew something about carbon in its guise as organic matter. Soil samples taken for fertility recommendations included a test for organic matter in the top six inches of soil as an indication of overall soil fertility and soil quality. It was generally accepted that soil organic matter had decreased by half after 100 years of farming, from about six per cent in native prairie down to three per cent in farmed acres.

The first time I remember popular discussion of global warming was in 1988, an extremely hot, dry year. It was a year of crop failure in South Dakota and the Midwest, and the year that Yellowstone burned. There had likely been some discussions of global temperatures rising in the rarified air of scientific journals for years, but public awareness was literally ignited by the fires in Yellowstone. The oppressive heat layered with the conflagration in Yellowstone created the images and an intuitive mash-up which inserted global warming into the vernacular.

The immediate rejoinder of skeptics was that one event does not make a trend. While 1988 was very hot and dry, so had been many other years. Was 1988 an indication of human induced warming or simply part of the normal range of climate? Looking at tree ring data shows many periods over the past several thousand years of heat and drought, and yet we were generally thought still to be in an ice age. Were we just trying to find something new to worry about?

The skeptics were right, of course. One year, or several years, does not define a trend. Skeptics ignored two things, however. First, weather data had been showing a warming climate for some time already. And second, we had a predicted and verified mechanism to create the warming – carbon dioxide. That has not eliminated a bitter fight, still going on, over the reality of warming and its cause.

An image was put forth in conservative circles of a cabal of conspiring scientists cooperating to reinforce a political view. The smoking gun was some emails that implied one researcher might fudge some data to make his model appear more accurate. That argument ignores both the heterogeneity of the scientific community and the number of researchers both cooperating and competing to create the best climate models. The study of any large question is an iterative process which starts from a single research paper from an individual or group. That paper is reviewed by several peers for quality and gets published in a journal. This will prompt responses, criticisms and new studies reviewed by new reviewers. Skeptics of the premise or the results get the opportunity to create studies or models which modify or even trash the original paper. Another researcher might buttress the original study with additions to the model, augmenting its ability to predict. As time goes by models are tweaked and adjusted as more years of data are available to plug in. While a sloppy study on a more esoteric topic might slip through the cracks without sufficient criticism, this really isn’t possible on a large and important topic like global warming. If your methodology or your reasoning is poor you will suffer the consequences professionally. Poor research will be punished. Good research will be rewarded with citations, invitations to speak at conferences and grants for further work. Eventually something approaching the truth will emerge.

Climate is influenced by a chaotic conglomeration of factors, making it almost certain that no model will ever be “right”; no model will be perfectly predictive. I think it is pretty clear that we have come to the point, however, where we are fine-tuning climate models. We are narrowing down the effects of feedback loops and trying to anticipate new factors which will arise as temperatures rise. The premise of human induced global warming, primarily caused by carbon dioxide created by the burning of fossil fuels, is here to stay.

Most of the history of life has actually occurred when temperatures were much warmer than they are today. There is nothing normal about today’s climate, though it seems normal to us. Many of the most densely populated areas on earth were under water 10-20 million years ago, and will be under water again in the future. During the much warmer climate of 50-100 million years ago there was no ice at the poles and about half of what we know as dry land was under the ocean. We would just prefer that Miami, New York City, Tokyo and most of Bangladesh don’t go under water in the foreseeable future, but that seems to be the path we are on, caused primarily by our pulling carbon out of the ground as coal, oil and natural gas and sending it up into the atmosphere as carbon dioxide.

So why am I belaboring arguments that more knowledgeable people have written books about? It is an introduction to what I hope is a significant contribution I can make through my restorations.

I wrote earlier that it was generally accepted that soils in this area, mostly broken out of prairie at the end of the 19th century, had lost half of their carbon after 100 years of farming. That trend, however, has clearly reversed. The combination of high residue farming, particularly no-till farming, and higher yields, has begun to store carbon again. Soils that measured 3% organic matter in 1980, when I began my career, now usually test at 4%, a gain of almost 6 tons per acre in the top 6″ of soil. We don’t know, however, what is happening below six inches and we don’t know where a new equilibrium might occur. It is possible that most of the gains that can be made by farming have already been made. It is almost certain that annual crops will be unable to duplicate the carbon storage of a deep rooted, diverse perennial prairie.

My restoration, along with my other attempts to bring prairie plants to the landscape will transition about 200 acres from annual agriculture to perennial (190 so far, 20 more this year). Though it may be hundreds of years before the ecological processes that stabilize a prairie mature, we should begin sequestering carbon immediately. Gathering more carbon to the soil will start with the first perennial. This will happen because of a cooler environment (no direct sunlight reaching the soil), the depth and quantity of perennial roots decomposing in situ and the lack of disturbance to the microbial environment that will allow the equilibrium to shift towards stable organic matter. We will create a less oxidizing environment.

How much additional carbon can we hope to sequester and stabilize? It is not as if the land is being abused now. My renter uses a three crop rotation with very little tillage. As I said earlier, we are probably already sequestering carbon. So, this spring I am planning to start what I hope is a long term documentation of changes in soil carbon in my prairie seeding compared to the adjoining cropped fields. If I am fortunate enough to live for another ten or fifteen years we might even get some preliminary answers. If I can sequester an extra percent of organic matter in the top foot of soil and an extra half percent in the next foot, a reasonable goal, that will add up to about 17 tons of carbon per acre or 3400 tons over 200 acres. Not too shabby.

What is that stored carbon worth? One can find an incredible range of monetary values for carbon, but I have repeatedly seen $50/ton as a conservative value for the societal worth of carbon. Thus, using those suppositions, my restorations could provide $170,000 of value to the world in removing carbon dioxide from the atmosphere and storing it in my soil. If the United States ever reaches a political consensus to enact a mandatory cap and trade marketplace, projects such as this might have a cash value. There is already a precedent in the Pacific Northwest where sustainably grazed ranches have sold carbon credits.

It is very speculative, but if the restorations eventually reach the carbon status of pre-settlement prairie then my carbon sequestration estimates are low. As I have stated in some earlier posts, I am playing the long game. The prairie restorations will continue to develop and the biotic relationships deepen for a very long time. By placing easements on the restorations I plan to allow them to “grow up and make something of themselves”. It might take a hundred years or more, but theoretical carbon sequestration of those 200 acres could reach 10,000 tons. Wouldn’t it be something if I can stick around long enough to document a measurable change? A cool goal like that makes a person look forward to jumping out of bed in the morning. We all need things to look forward to, and I am really looking forward to getting started on establishing the baseline measurements this spring. Stay tuned, the excitement is only beginning.