Agriculture and Climate

Agriculture and Climate Change

While local pollution can be harmful, some of the overarching methods used in agriculture can significantly affect our global climate. In fact, agricultural activity is one of the leading causes of anthropogenic climate change—the unintentional alteration of the planetary climate caused by human activity.

It's not all cut-and-dried: growing some tomatoes in your backyard will not have any relationship to climate change. Rather, the reason agriculture has such a big impact on the climate is because of the processes farmers have to undertake to make large-scale agriculture feasible.

Agriculture and Climate Effects

To create space for more crops, farmers may need to cut down part or all of a forest. As you know, trees love to breathe in carbon dioxide; deforestation releases carbon they were storing, and with fewer trees, less carbon can be sequestered away from the atmosphere.

Industrial-scale crop-based agriculture requires the use of large, fossil-fuel-powered machinery, like tractors and combines, which release greenhouse gases. Similarly, transporting food from the farm also causes greenhouse gas emissions, especially if it is being exported to a country on the other side of the planet.

Massive herds of cattle, such as those found in industrial livestock farms, can actually generate substantial amounts of methane through their belching and flatulence. Similarly, the traditional method of growing rice—flooding to create rice paddies—attracts large quantities of microbes that release huge amounts of methane. Some fertilizers also release nitrous oxide.

Fig. 1 - Industrial cattle farming can generate profound amounts of methane

Ultimately, even placing transportation in a separate category, agriculture and forestry account for around 11% of all greenhouse gas emissions in the United States. Globally, agriculture and forestry account for around 24 to 30% of all greenhouse gas emissions.

Agriculture and Climate Impacts

As the Earth warms due to climate change, agriculture will become more difficult. As agriculture becomes more difficult, more intensive agricultural methods will need to be applied to farms to get the same agricultural output, which will cause even more greenhouse gas emissions, leading to further global warming. It's a seemingly endless positive feedback loop.

Fig. 2 - Farms may become less productive due to climate change

Besides average higher temperatures (with which some crops and livestock may not be able to cope), climate change is also causing extreme weather events to become more common. Crops are not immune to wildfires or hurricanes, but droughts are particularly pertinent to agriculture. Farmers in many agricultural regions that have just enough water to support their plants and animals will find themselves unable to maintain their farms without sacrificing their water supplies. Similarly, a general lack of water may cause soil erosion to occur more quickly, leading to desertification, the process by which worn-out soil becomes more desert-like. A significant decline in agricultural production can lead to starvation in some areas.

Agriculture and Climate Adaption

It's all well and good to identify all of the environmental problems created by agriculture, but the frank truth is, we need agriculture and farming. Unless you get all your food from hunting and gathering, you likely benefit greatly from our agricultural systems. Chances are, just about everything you've eaten today originally came from a farm or garden. Even the saltiest, greasiest French fries began life as potatoes, and the sweetest milk chocolate bar used to be a cacao bean. Indeed, the rise of agriculture is also tied to the rise of civilization; in a way, the invention of farming ultimately led to the creation of the technology you're using to read this article right now (check out our explanation on Agricultural Hearths for more information!).

Agriculture enables us to produce enough food to support an ever-increasing population. At this point in history, a widespread return to hunting and gathering is neither realistic nor feasible. So how do we adapt our agriculture to both meet the needs of our ever-expanding population and reduce environmental impacts?

There are three major approaches to agricultural climate adaptation: sustainable agriculture, biotechnology, and changing diets.

Sustainable Agriculture

Sustainable agriculture is an approach to agriculture that involves modifying the techniques we already have in place to make them less impactful on the environment. In other words, the goal is to make our farming practices more feasible long-term. Farmers can use sustainable principles to get the most out of their resources while decreasing their environmental impact—usually a win-win.

There are dozens of different sustainable farming methods, including but not limited to:

• Rotational grazing

• Crop rotation

• Cover crops

• Vertical farming

• Multicropping

Biotechnology

Another way to adapt to a changing climate is to develop plants and animals that are hardier and more resilient. Enter genetically modified organisms (GMOs). Strictly speaking, the very process of domesticating wild plants and animals for use in human agriculture was a form of genetic modification, and modern GMOs continue that tradition. However, genetic modification these days differs from selective breeding in that DNA composition can be changed directly in laboratories using biotechnological processes. This makes GMOs controversial, as they seem to do away with natural processes altogether, the possible consequences of which are not yet fully known. "Organic" has recently become a buzzword in supermarkets to advertise produce that is not genetically modified.

Fig. 3 - Organic produce has gained popularity in response to skepticism about GMOs

Similarly, biotechnologists have begun cultivating lab-grown meat. This artificial meat is significantly less environmentally demanding than livestock agriculture but faces the same skepticism as GMOs.

Changing Diets

Incorporating lab-grown meat into your diet might seem gross, but the simple act of reducing beef consumption, in general, may have a positive effect on the environment. If demand for beef decreases, herds may become smaller, as will their methane output. Chicken and pork both have a smaller impact on the climate than beef, though meat overall can be more environmentally demanding than produce.

Entomophagy, the consumption of insects, has been suggested as an alternative to our current diets. The very notion may seem unappealing to some, but insects are an extremely efficient source of protein. They are cheaper to farm, have a smaller environmental impact, and can provide more protein per gram than other forms of meat.

A hidden cause of agriculture-related climate change is food waste. In the United States, over $150 billion worth of food is wasted and thrown away each year. Overbuying (and wasting) food is an unwitting signal to the agricultural industry and governments that they need to produce more and more food to meet demands.