The global environmental footprint of food, from a new angle – Anthropocene Magazine

Creating a sustainable human age we actually want to live in. 

Join thousands of researchers, policymakers, designers, and educators who rely on Anthropocene to keep up to date on the latest sustainability science and innovations.
more about our newsletters>

Sign Up
Sign up for Anthropocene’s free newsletters

Sign Up
Almost half the cumulative environmental impact of our food systems derives from just five countries. This, plus a host of other revelations about food impacts, have been shared in a new study, which its authors say could help tailor efforts to make global production more sustainable.
Usually, we tally food impacts by, for instance, looking at the greenhouse gas (GHG) emissions linked to a liter of milk. But this single-impact focus, usually applied to distinct food groups, fails to capture the full catalog of pressures—like habitat destruction and water use—that foods place on the environment. It also overlooks the fact that the impacts of food production aren’t felt uniformly across the planet, but will vary geographically, especially when factoring in GHG emissions and other transboundary impacts. 
The researchers on the new Nature Sustainability study hoped to counter these shortcomings with a different way of estimating the pressures that food systems place on our planet. Their study pooled global production data from 2017, covering 99% of global food products, and originating from 172 nations. They looked at four environmental impacts associated with the production of each food in each country: greenhouse gas emissions, nutrient pollution from fertilizer run-off, freshwater use, and habitat disturbance. 
Crucially, they then combined these four pressures to create one geographically-explicit estimate of cumulative food production impacts in each case.
In the first instance, this approach revealed that responsibility for global food impacts is heavily skewed to specific parts of the planet. In fact, just five nations—India, China, the United States, Brazil, and Pakistan—account for 43.8% of the global cumulative impact of producing food, the study shows.
Of this, terrestrial food production contributes a larger cumulative pressure than do aquatic sources of food. And yet, despite providing just 1.1% of global nourishment, food from the ocean causes a surprisingly large 10% of cumulative environmental pressure, due to the effects of habitat disturbance, the researchers found. 
Meanwhile, nearly all this environmental pressure—about 92%—plays out on just 10% of Earth’s surface, mainly in India, China, the United States, Brazil and Indonesia, the analysis showed.
Measuring the fuller cumulative pressures of different food types also revealed some surprising new high-impact candidates. Beef production is widely accepted as being the worst for the planet because of the associated emissions—but when factoring in water use and pollution, pig farming actually has the larger cumulative environmental footprint. Similarly, some types of fish pose bigger environmental pressures than chicken does. 
When impacts were interrogated at national scales, the results morphed again, revealing that for most nations (with the exception of countries like Brazil) the largest cumulative environmental pressures come from crops such as rice and wheat, which need large amounts of water and cause lots of nutrient pollution.
Drilling further into national differences in food production impacts, the researchers also discovered how variable production methods around the world can dramatically alter the environmental footprints of similar foods. Across nations, the environmental pressures posed by the same food types varied up to tenfold, depending on where those foods were produced. 
Take soybeans, which are 2.4 times more efficient—and therefore less impactful—when farmed in America than in India, because US farmers have access to technologies that have helped them increase yields and lower GHG emissions. 
The researchers explain how this comprehensive assessment of food production pressures, distinguished by geography, creates new vantage points on the problem—and with it, new opportunities to tackle it.
For instance, identifying the major ‘culprit’ nations behind the majority of global food impacts helps illuminate where interventions might have the biggest global effect. Finding where food systems impose their biggest planetary impacts could guide mitigation and remediation efforts in those regions. And at more localized scales, comparing the footprints of similar foods across nations could reveal where farming methods in some countries could be improved to bring impacts down, the researchers say
“We need this comprehensive information to make more accurate decisions about what we eat.”
Halpern et. al. “The environmental footprint of global food production.” Nature Sustainability. 2022.
Image: ©Anthropocene Magazine
What to Read Next

In a happy accident, a beaver dam built in the middle of a river research project illuminated how their presence improved water quality
Warren Cornwall
Researchers developed a clever algorithm to coordinate whole neighborhoods of air conditioners, water heaters, and heat pumps—all without comprising individual use.
Sarah DeWeerdt
In buildings with lots of people, CO2 emissions from human respiration is surprisingly high; a research team wondered if HVAC could be unlikely companion to food production.
Emma Bryce
Food & Agriculture
Climate Parables

Sign up for Anthropocene’s free newsletters

Sign Up
©2022 Anthropocene Magazine | All rights reserved

We will never share your email address unless you allow us to do so. 
View our privacy policy. Easy unsubscribe links are provided in every email.
Smart, powerful environmental journalism doesn’t come cheap. Anthropocene is science-based, nonprofit—and reader-funded. 


Related Articles

Leave a Reply

Your email address will not be published. Required fields are marked *

Back to top button