In a previous article
I published here, I presented the different opinions that exist about the causes of global warming in recent decades, and I also brought to the attention of readers the opinion of researchers who deny that human activity in the last 150 years is the main cause for it. According to these researchers, global warming is part of a million-year-old cyclical process, in which the world warms and cools intermittently, in cycles of hundreds and thousands of years, due to changes occurring across the sun and their interactions with the oceans and earth. We are simply in a warming period after a long ice age, without being able to predict its intensity and duration. What we do know is that the flora and fauna on earth have survived these changes over the years and have even evolved over the globe. In my previous article I had raised the thought that if the researchers who support this approach are right, then, when it comes to cattle raising, there is room to divert the huge budgets the world spends to replace “polluting” energy sources, with “clean” ones, and spend it in the development of tools that will enable animal raising in warmer conditions. In this article, I intend to refute the prevailing public opinion, in that agriculture, and especially the cattle industries, are among the main contributors to global warming, mainly because of the methane gas they emit into the atmosphere.
The gases that contribute to the greenhouse effect are divided into direct greenhouse gases, whose presence in the atmosphere directly affects the rise in earth temperature, and indirect greenhouse gases, which contribute to the greenhouse effect following atmospheric chemical reactions. The impact of each of these gases is estimated based on two characteristics: the warming potential (GWP: Global Warming Potential) and the length of their stay in the atmosphere (atmospheric life). The GWP value represents the emission coefficient for converting emissions to CO2 value (CO2 equivalent). Emissions from the agricultural sector consist of direct gases (carbon dioxide CO2, methane CH4 and Nitrose oxide N2O) and indirect gases (ammonia NH3, carbon dioxide CO and sulfur dioxide SO2). In this article, I will refer only to the effects of direct gases, whose heating potential can be seen from Table 1.
Methane makes up about 10% of all greenhouse gases emitted into the atmosphere, with 45% coming from agriculture. In other words, methane gas contributes about 5% of the total greenhouse gas emissions into the atmosphere, with the share of cattle industry not exceeding 3%. What is more important is the fact that about 95% of the carbon from the methane emitted by the cattle into the atmosphere is returned to the ground and bound by the plants, with only 5% of it, remaining “trapped” in the atmosphere.
Emission of methane into the atmosphere by cattle is at the center of the current criticism in the world, which considers these industries as primarily responsible for the “greenhouse effect” and global warming, and all the damages that result. This attitude can have extremely negative impact on the agricultural industries and especially on the beef and dairy cattle sectors. The major part of the methane gas that reaches the atmosphere undergoes a process of chemical decomposition by oxidation, stays in the atmosphere for a relatively short time and enters a “biogenic cycle” that involves carbon binding to plants in the soil, making its “warming” effect minimal. Therefore, this methane can be considered a “sustainable” gas. The carbon coming from methane binds to plants, which are later used as food for the cattle, whose digestion is the source of the methane gas emitted to the atmosphere. There is a closing of the circle here, and all this is happening, with little, if any, effect on the concentration of greenhouse gases in the atmosphere. In general, there is almost equality in the ratio between the amount of methane emitted into the atmosphere by the cattle and which is absorbed back by the vegetation, which means that the contribution of the methane gas from cattle origin to the greenhouse effect is very low. It is clear to us today that, when it comes to discussing cattle raising contribution to global warming, the term CO2 equivalent is misleading, and irrelevant.
The issue raised in this paper is of paramount importance when it comes to the digestive system of ruminants, for its unique ability to digest plant cellulose, which is the main “carbon binder” in nature and the main food source of all ruminants. About two-thirds of the earth’s land relevant to any agricultural activity is defined as “marginal land” which, for reasons of land quality or topographic constraints, are not suitable for intensive agricultural cultivation and can only be used for grazing. It has been found that the “carbon binding” capacity of pastures, as well as the fields where roughages are grown and consumed or harvested frequently, does not fall short of that of forests, and even exceeds them (carbon binding capacity is directly proportional to plant growth and frequency of grazing or harvesting). Recent studies in the United States and Italy on greenhouse gas emissions in cattle breeding processes have found that the amount of carbon dioxide generated by the decomposition of methane emitted by the cattle into the atmosphere not only does not increase greenhouse gas concentrations, but also reduces them. Carbon emissions from cattle in the production processes are about 30% lower than the amount of carbon fixated in the grazing and forages growing process, so cattle does not increase the concentration of greenhouse gases in the atmosphere but also decreases it.
Another point I would like to raise in this article is the growing shift of people to veganism, while giving up consuming animal products. Part of these people take this decision due to the contribution of animal husbandry to global warming. In many cases, these people are acting (consciously and perhaps unconsciously) against the “order of their conscience” and I would like to clarify this point here. Human transition to veganism and complete avoidance of consuming animal products will reduce greenhouse gas emissions by 0.8 ton of CO2 per year, half of the amount of CO2 emitted to atmosphere in one transatlantic flight a year.
Owning a private car, or turning on an air conditioner in the summer and a stove in the winter, will release into the atmosphere an amount of carbon dioxide that exceeds tens of times more than not eating meat and drinking milk. The carbon dioxide emitted in this case will come from burning fossil fuels and may remain in the atmosphere for many years and really contribute to global warming. Let see those vegans stop first with these activities!
In conclusion, agricultural farming in general, and cattle raising in particular, not only do not contribute to global warming, but even help reduce it. It is desirable that all those engaged in making their living from agriculture, and especially beef and dairy cattle breeders, should be familiar with this data and take care to pass it on to their immediate environment.