You’ve probably heard methane from cattle is a big contributor to climate change.
While it’s true that methane is a highly potent greenhouse gas, let me tell you why context is key here. Cattle produce methane in their rumen as part of their digestive process, but so do wild ruminants like bison, water buffalo, elk and giraffes. There are also other large natural sources of methane like wetlands and volcanoes on the ocean floor.
So why is methane build up so significant in the modern era? The short answer is that methane from natural sources and from anthropogenic (human created) methane act very differently in the atmosphere.
First, some background.
During photosynthesis, plants split water into two ions, one of these being a hydroxyl ion. Hydroxyl ions are highly reactive with methane. Methane released from a cow’s rumen is not directly released into the upper atmosphere, it’s released into what’s called the near earth atmosphere (NEA) where, through a series of reactions with hydroxyl ions, that methane is broken down into water vapor and carbon dioxide.
This is why context matters; for methane to express its outsized “global warming potential” it has to persist in the atmosphere and make it out of the NEA without being broken down. When a cow, bison or buffalo, is out grazing on green growing grass (like on a regenerative ranch) and they burp up some methane, it’s released into an environment that is highly saturated with photosynthesizing plants and hydroxyl ions, so that methane does not make it into the atmosphere.
The same can be said for other natural sources of methane. Hydroxyl ions are also created by evaporating water, think a sunny wetland lake the Florida everglades, or the surface of the ocean as that methane bubbles up from a volcanic vent.
Nature also has some other fascinating means to regulate atmospheric methane. Isoprene is a volatile organic compound released into the atmosphere during plant growth. Isoprene acts a buffer in the atmosphere, so as methane goes up, isoprene reacts with it removing it from the atmosphere. Unfortunately, through deforestation and desertification, we have compromised these systems.
Now think of those anthropogenic sources of methane: cars sitting bumper to bumper on a highway, a leaky natural gas well where the flaring stack isn’t igniting, a manure lagoon, or unfortunately, cows sitting in massive feed lot. There are no green growing plants in sight.
These considerations are almost never factored in when scientists look at the sources of methane and assign its impact to cattle. It is important to select grass-fed grass finished beef where cattle are grazing their entire lives, but in the beef industry overall, cattle spend the majority of their lives on grass before going to a feedlot. This is just never accounted for.
Now we get to the elephant in the room. New research as been published looking back at our accounting methods for atmospheric methane. It turns out that scientists had been asking the fossil fuel industry how much methane they were emitting and taking their reports as accurate. The scientists then said, we have a pretty good idea of how much methane is coming from other natural sources, and from industry, so what ever is left must come from livestock. Turns out the fossil fuel industry was massively under reporting its emissions. Scientists are still figuring out how off these reports were, but some estimates say that the actual emissions from these companies are 10 times what those reports sated.
You can read more about that here.
Its important that we accurately assign the impact of methane to the industries that are putting it into the atmosphere. Most of the time those folks that blame cattle for climate change are well meaning, they think cows are a major factor and connect the issue to the animal cruelty of the factory farming system, but they are misinformed. We should be confident in saying that grass-fed grass finished beef raised on regenerative ranches is helping to revegetate landscapes, is storing carbon, is healthy, and is cruelty free. The more we understand about the disruption to the climate system, the more regenerative ranching needs to be seen as a critical tool in revegetation and climate healing.