Meat consumption and Climate change: Do the numbers speak for themselves?

One of the major lifestyle changes among the personal choices to reduce your contribution to worsening climate change is eating less or no meat. If everyone goes vegan, then it is estimated that food-related Greenhouse Gases (GHGs) can be reduced by three quarters. There is always a way to tell a story that can sound impactful but does it portray the entire picture? Few of the major pillars of reasoning against meat consumption are discussed here, if not in entirety but surely not in a cherry-picking manner.

GHG emissions from livestock

It all started with a report (Livestock’s Long Shadow, LLS) published in 2006 that said that 18% of the global GHG emissions are from livestock alone which is more than the emission from the entire transportation sector alone. This has been one of the major arguments against the environmental footprint of livestock.

The food agriculture organization (FAO 2013) updated this number to 14.5% of global GHG emissions. If we dig deeper, the number 14.5% is obtained through life cycle assessment during the calculation of GHG for livestock i.e contribution from the soil use, fertilizers, plants, belching, manure, feed processing, and so on till it ends up in our stomach when it is being compared against transport emissions, only tailpipe emission is being considered, not the life cycle assessment of the transport sector that would include production of vehicles, the materials, and the construction for these facilities (airports). This comparison is as similar to comparing apples to oranges.

Cows (ruminants) and their gaseous stomach

All ruminants (animals with rumen) like cows, buffaloes, and goats digest their food through enteric fermentation and in the process, belch out CH₄ which is 25 times more powerful GHG than CO₂. One could ask if the increase in livestock population increased GHG contribution lately. The answer is most likely to be no. For example, in the US alone, the historic population and current population of ruminants have not changed significantly.

Even if we shut livestock to nullity, this would mean that the fertilizers that we use for crop production will now be entirely dependent on chemical fertilizers (at present, 50% of fertilizer is manure from livestock). Producing chemical fertilizers are energy intensive which again releases GHGs during the process.

Land use for grazing

There’s no denying that livestock has a big environmental footprint. 26% of the earth’s total land area is for livestock. Out of the entire land that can be used for agriculture, ⅔ is used for cattle grazing but this portion of land is marginal (non-arable) i.e it cannot be used to grow crops for human consumption due to factors like improper soil conditions, insufficient water availability, topographical inadequacy.

So, even if crops are farmed in these regions, the harvest still remains inedible for human consumption. The food that we feed livestock is a product of harvest from the non-arable land. Out of all the feed, 84-86 % is non-human edible (Livestock: On our plates or eating at our table? A new analysis of the feed/food debate) so the argument that grazing land harvest could feed 3.5 billion people doesn't hold true. However, clearing out forests to make land available for grazing is an issue of concern.

Are these animals super thirsty?

Water consumption estimates say that producing 1 kg of steak uses 15 kl of water or 1 pound of meat needs 660 gallons of water. This is an enormous amount but the estimate doesn't mean water consumption in form of drinking water, rather 91% of it is green water (rainwater).

This is used up by the grass/ crops in the non-arable areas and eventually as feed for livestock. The main concern is the overuse of freshwater reserves for crop irrigation, currently, this is 70% of the available freshwater reserve. US geological survey estimated non-green water requirements to produce one-quarter pound of bread, rice, beef, and California Almonds. Clearly, the almonds stand tall.

Calorie comparison: Huge intake, tiny output

This argument again takes the harvest from non-arable land which states that through livestock, we get only 18% of the calories that we feed in form of products like meat and dairy. The validity of this argument vanishes because a human diet isn't focused on meeting calories but it is about meeting the nutrient requirements. If it was only the calorie-specific argument, Prof. Dr. Frank Mitloehner, an air-quality specialist from UC Davis gives an example of consuming coco cola as it has almost zero carbon footprint and is high in calories.

Food waste: The real problem with food

If there is a personal choice to reduce your contribution to worsening climate change it's not avoiding meat but avoiding the contribution to food waste. Out of all food waste produced in the world, 40% of them in developed countries is wasted at the consumer level and 40% of them in developing countries is wasted at the producer (farmer) level. The latter is a consequence of insufficient types of machinery available for harvesting at the right time.

With proper regulations, a reduction in the production of food waste can reduce the use of resources, feed more people, and contribute less to landfills.

So, while a different diet is definitely more climate friendly, it turns out that the food waste production is the face of the environmental footprint.

Which of the following personal choice would you opt for towards climate change (CC)?

• Switch to electric car (eventually car free)
• Have one fewer child
• Wash clothes in cold water (washing machine)
• Eat a plant based diet

See All Options

References

Gerber, Pierre J., et al. Tackling climate change through livestock: a global assessment of emissions and mitigation opportunities. Food and Agriculture Organization of the United Nations (FAO), 2013.

“Why Meat is the Best Worst Thing in the World” YouTube, uploaded by Kurzgesagt – In a Nutshell

, 30 September 2018, https://www.youtube.com/watch?v=NxvQPzrg2Wg.

Poore, Joseph, and Thomas Nemecek. "Reducing food’s environmental impacts through producers and consumers." Science 360.6392 (2018): 987-992.

“Eating less Meat won't save the Planet. Here's Why” YouTube, uploaded by What I've Learned, 26 April 2021, https://www.youtube.com/watch?v=sGG-A80Tl5g&t=302s.

Mekonnen, Mesfin, and Arjen Y. Hoekstra. "The green, blue and grey water footprint of farm animals and animal products. Volume 2: Appendices." (2010).

Cassidy, Emily S., et al. "Redefining agricultural yields: from tonnes to people nourished per hectare." Environmental Research Letters 8.3 (2013): 034015.