World Watch Article

World Watch Article

more livestock & climate connections

This page provides links to original publications, as well as breakdowns explaining how the livestock sector was calculated to contribute more than half of all human-caused greenhouse gases.

Due to the overwhelming response to World Watch Magazine’s (WWM) November/December 2009 lead story “Livestock and Climate Change” (free PDF – $6 full mag), a follow-up Critical Comments and Responses was published in March/April 2010 (free PDF).


The WWM article is a recalculation of the seminal UN-FAO 2006 report – Livestock’s Long Shadow where livestock were said to produce more greenhouse gases than ALL transportation combined – 18% (free PDF).

This WWM article calculates that the livestock sector is responsible for 51% of human-caused greenhouse gas emissions.

November 2009 – Original Article

The lead article Livestock and Climate Change in the Nov/Dec 2009 issue of World Watch Magazine (a publication of the Worldwatch Institute) describes a new case for powerful action that can be taken jointly by citizens/consumers, government, industry, investors, and environmentalists.

It focuses not only on CO2 or fossil fuel or methane reductions, or on forest protection and regeneration — but all at the same time.

Reducing livestock quantities would reduce CO2 emissions over the long-term and methane over the short-term, while at the same time protecting and regenerating forest (the critical way to absorb carbon on a large scale).

The authors demonstrate that livestock produced greenhouse gases are much greater than previously thought, both in absolute and relative terms. We may now have the breakthrough for that has been sought to reverse climate change.

“Livestock and Climate Change: What if the key actors in climate change are…cows, pigs, and chickens?”

From the Worldwatch Institute – 10/20/09: The environmental impact of the lifecycle and supply chain of animals raised for food has been vastly underestimated, and in fact accounts for at least half of all human-caused greenhouse gases (GHGs), according to Robert Goodland and Jeff Anhang, co-authors of “Livestock and Climate Change”.

A widely cited 2006 report by the United Nations Food and Agriculture Organization, Livestock’s Long Shadow, estimates that 18 percent of annual worldwide GHG emissions are attributable to cattle, buffalo, sheep, goats, camels, pigs, and poultry. But recent analysis by Goodland and Anhang finds that livestock and their byproducts actually account for at least 32.6 billion tons of carbon dioxide per year, or 51 percent of annual worldwide GHG emissions.

Full WWM article “Livestock and Climate Change

Sources and Q&APurchase WWM issue

At-a-Glance Highlights

  • Overlooked – inclusion of respiration more than doubles livestock’s annual GHGs.
  • Overlooked – the FAO only includes the change in land use and deforestation which is relatively small compared to the land already in use for livestock production. Significant GHG reductions from photosynthesis are foregone by using 26% of land for grazing and 33% of arable land for growing feed.
  • Underestimated – methane has a much shorter half-life (8 years) than CO (100 years). The FAO and others have considered methane to be 21-25x stronger than CO2  by using a 100-year time-frame. The International Panel on Climate Change recommends using a 20-year time-frame instead, thus increasing methane’s global warming potential (GWP) to 72. The short half-life and high GWP means that methane reductions have a faster impact on climate change than CO2 reductions. Goodland and Anhang use the FAO’s 37% for their methane calculation and increase the total GHG to accommodate the increased GHG. The author’s note that the additional research is need to increase the world’s total GHG level from non-livestock sources of methane.
  • Underestimated – the FAO uses dated statistics from 2002 and earlier. Livestock alone have increased 12% since 2002.
  • Underestimated – the FAO decreased official livestock counts by more than half (for example using 33 million tonnes for poultry instead of their own Food Outlook report of 72.9).
  • Misallocated excludes livestock deforestation in Argentina (and other places).
  • Misallocated excludes farmed fish (for feed and direct human consumption).

Uncounted, Overlooked, and Misallocated Livestock-related GHG Emissions

(Table p.11)


Annual GHG emissions (CO2e), million tonnes

Percentage of
worldwide total

FAO estimate



Uncounted in current GHG inventories

1. Overlooked respiration by livestock



2. Overlooked land use



3. Undercounted methane



4. Other four categories (see text)






Misallocated in current GHG inventories


5. Three categories (see text)



Total GHGs attributable to livestock products



* FAO starting percentage is decreased from 18% since total emissions are greater.

About the Authors

Dr. Robert Goodland served the World Bank Group as their Environmental Adviser for 23 years, during which time he drafted and persuaded the Bank to adopt most of its current social and environmental policies. He was then appointed as the technical director of the independent Extractive Industries Review of the World Bank’s oil, gas and mining portfolio. He was elected president of the International Association for Impact Assessment, and Metro Chair of the Ecological Society of America. He was honored in 2008 as the first recipient of the Coolidge medal for lifetime achievement in environmental conservation, presented by the prestigious International Union for Conservation of Nature (IUCN).

Jeff Anhang is a research officer and environmental specialist at the World Bank Group’s International Finance Corporation (IFC). He advises companies on managing environmental and social risks and opportunities. He has worked to establish a public accountability mechanism for IFC, and a program to improve IFC’s environmental and social footprint.