Climate change is here

BY ART CULLEN

We’ve been reading up on climate change and how it might affect agriculture and food processing. First, you should be happy to know that Iowa State University and its associated labs have taken the lead in research and reporting. Deserving special note are Drs. Gene Takle, Jerry Hatfield and Rick Cruse, who have contributed substantially to the national discussion; Takle shared in a Nobel Prize for his work on climate modeling. These are top-flight scientists, agronomists and climatologists who have issued sober analysis about climate impacts.

We were going to say “potential” impacts.

They are not potential. They are here.

You recognize it when reading Takle’s summary of the 2014 White House Report on Climate Change and Agriculture, on which we reported at the time. But we missed this important part: Soil is carrying more moisture than before 1980. That is the first impact.

The Des Moines lobe region where Storm Lake sits — that great flat expanse that grows the most corn in the world —  has witnessed a big increase in drainage capacity over the past 30 years, Takle and Cruse note. They argue that the biggest driver is the more extreme rainfalls we have witnessed in recent years. Cruse documents the more severe rains at his daily erosion website.

Farmers and landowners have to get rid of that water immediately because the ground is too expensive and the stakes are too high to leave it wet. Google it and the numbers are all there: Drainage tile pays for itself and then some.

There are other factors, but increased rainfall onto the Des Moines lobe’s thick glacial remains is the main contributor to increased, and more efficient, drainage.

That more efficient drainage system delivers nitrate to the Raccoon River in increasing amounts. Which caused the Des Moines Water Works to sue Buena Vista, Calhoun and Sac counties. The case was dismissed by a federal judge because the districts only have authority to remove water. Under state law, they must remove water under petition from the landowners of the drainage district.

The water works is confounded. Its only expensive recourse is to treat the water so people in Des Moines may safely drink it, then dump the nitrate back into the river downstream of Des Moines so that the Mississippi River can transport it to the Gulf of Mexico. The people of greater Des Moines are already paying for climate change in their water bills. That is what is happening now.

It’s not because of bad farming necessarily. Most farmers try to do the right thing within the framework of staying afloat. Laying tile is a logical response to a flooded field that costs $10,000 per acre. But that tile was not necessary 35 years ago. Something changed.

It was the climate.

And it was a more intensive agriculture. Livestock left the Buena Vista County landscape, largely. Grass was replaced by rows of corn and soybeans over the past 30 years.

The water works complaint is mainly with the tiling. Systems have been improved all along, and some have been laid new since. Where a farmer once could reliably get a solid yield in a low spot he could not anymore because of more moisture. That is climate change. So he improved drainage and got a better yield yet.

The drainage comes at a cost. First, in the infrastructure. Second, downstream.

We did not have much of a nitrate problem in the Raccoon before 1980. We do now. We also have a growing toxic algae problem in our rivers and lakes caused by soil erosion even on our flat ground. The rains become so extreme, up to 11 inches at a draw, that they can take 20 tons of soil of an acre in a day. The soil regenerates itself at a half-ton a year. The soil that is lost to the river is laden with phosphorous. It grows deadly toxins from the algae.

These impacts are all largely climate-induced.

Climate change was the proximate cause of the Des Moines Water Works lawsuit.

Corn yields are increasing because, in part, of increased soil moisture remediated by drainage. However, corn yields already show protein quality losses because of degraded soil in the Des Moines lobe complex wrought by extreme rainfalls. If it keeps up, and if our temperature warms as Takle projects, our corn yields could drop in half absent genetic breakthroughs.

Those types of climate impacts affect livestock and renewable fuels production.

We are adapting to it already.

Climate change is upon us, no matter what you think caused it. Drainage systems and river pollution are a direct result. It is putting more pressure on producers to invest in soil conservation techniques and improved drainage systems. And, climate change is helping to deplete Midwest underground water aquifers faster than their recharge rates, which has enormous implications for ethanol and livestock production.

The body politic remains skeptical. The legislature tried to eliminate the Leopold Center for Sustainable Agriculture at Iowa State, to which Dr. Cruse contributes. It tried to eliminate the Des Moines Water Works for being a pest. And it did nothing to make Iowa more resilient in the face of climate change. The conversation is starting to change as denial fades, but it is a slow process. Read up and your mind starts to change.