Global Climate Change, popularly and erroneously known as “Global Warming”, is a serious and accelerating problem. Rapid shifts in climate have been responsible for major extinction events in the Earth’s history, such as the one that eradicated dinosaurs. We are in the midst of a similarly rapid and large-scale shift in climate now, and it threatens all of us with calamity.
So it is true that climate does cycle due to natural causes, but two points are germane:
(1) Rapid climate change produces major perturbations in the Earth’s ecosystem, and since human beings depend on this ecosystem, we will suffer massive problems as the result of the current extremely rapid shift in climate. So even it it weren’t largely anthropogenic (caused by humans, which the data clearly show it is), would that matter? If a massive asteroid were hurtling toward Earth, threatening large-scale catastrophe on the human race, would we decline to try and avert this disaster simply because it wasn’t human-caused?
(2) The fact that this most recent climate change event is anthropogenic actually provides a reason for hope. If we are the major cause of climate change, the chances are much better that we can stop or even reverse the damage we have done, thereby saving ourselves from the consequences of this disaster. So the question becomes: what are we doing that causes our climate to change, and what can we do to mitigate this effect?
Some of the biggest contributers to anthropogenic climate change, which rarely get mentioned to the general public, are Concentrated Animal Feed Operations, or CAFOs. These include dairies, from which we get milk and cheese, and hog farms, from which we get bacon, ham, sausage, and so on.
Production waste from CAFOs is enormous. Dairies alone generate nearly 20% of the world’s greenhouse gases (GHGs) and more than one billion pounds of waste per day. In addition, volatile gases such as hydrogen sulfide, nitric acid, phosphates, and ammonia produced from the waste of CAFOs results in an intense stench, which leads to oppressive, unhealthy work conditions and odor regulations in many states.
Managing CAFO Waste
Typical techniques for managing this waste are expensive, labor-intensive, and only partially effective. These techniques include dry waste systems, liquid waste systems, or combinations of the two.
The dry waste system is the most basic. This system is employed on farms where dairy cattle are kept on open farmland and consists of collecting the manure then spreading it elsewhere. Given that there are ~92,000 dairy farms and ~62,000 hog farms that generate about three billion pounds of waste per day, you can see where it quickly becomes infeasible to simply spread this waste around on open land.
In the liquid waste system, stock animals are housed in sheds, stalls, or parlors, often with concrete floors. These floors contain drain gutters into which the animals excrete their waste, which is then flushed with water, through a solid separator, and into large holding ponds known as lagoons. In many cases, lagoon water is recycled as flush water, but only until it becomes too dirty for this purpose. It is also used as irrigation water for crops, which works well in the short-term. However, over the longer term, irrigating with lagoon water causes salinization of the soil, which reduces or eliminates its ability to produce crops.
There is a third option: anaerobic digestion, otherwise known as methane digester technology. In this system, waste is collected into a large, sealed container and allowed to decompose under anaerobic (free of Oxygen) conditions. This process converts much of the waste into methane, which can be collected and used as a relatively clean-burning fuel to run either an electric generator, or burned directly wherever you would use natural gas or propane. One huge advantage of this approach is that it captures methane, which is then converted to CO2 by combustion. Why is this advantageous? Because a molecule of methane has about 21 times the warming effect of a molecule of CO2, and the methane would otherwise simply be released into the atmosphere if not captured as part of a controlled digestion process.
So, as the global population increases (currently nearing 7 billion), the need to produce more food increases as well. Unfortunately, much of how we supply food now is not sustainable, at least in part because production techniques like CAFOs heavily contribute to anthropogenic climate change. The good news is that since we human beings have caused this most recent shift in climate, there is a real chance that we can take effective steps to mitigate or even eliminate the damage we have done. It’s about time we agree to acknowledge the gravity of this problem and take earnest steps as a civilization to redress it.