Reading the U.N. report on climate change and food supply

Vet Advice with Dr. Ron Clarke

Everyone involved with livestock industries should be aware of what the United Nations’ Intergovernmental Panel on Climate Change (IPCC) published in their latest report. First, it’s important to recognize the existence of this enormous and noteworthy group of international scientists, experts, advisors, authors, editors and reviewers. Then, more importantly, to understand the message incorporated in its 1,200 pages. Veterinarians everywhere must be prepared to address questions by clients and the public about “the land” and the implied criticism of agriculture — especially the livestock industry — for spurring climate change. The report contends that if left unchecked, rising temperatures, extreme weather and land degradation could trigger a global food crisis.

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Confucius wrote that calling things by their proper name is the beginning of wisdom. Climate science has its own specialized vocabulary and jargon. Readers should prepare to become familiar with another language; then decipher the many scientific assumptions presented as fact to help quell immediate fears North America sits on the cusp of food shortages and that everything is going to hell in a hand basket because of climate change. As veterinarians, we must prepare ourselves to allay fear in the minds of those who will misinterpret what’s being said, but to do so in a logical and reasoned manner.

IPCC’s overall goal, which paralleled the goals of authors Hawken and Wilkinson in their book titled Drawdown, is to limit global warming to 1.5 degrees, possibly two degrees Celsius, by sequestering carbon from carbon dioxide and limiting gases such as methane in the atmosphere. Scientists recognize that “the land” has an essential role to play. Linked to land use are other crucial initiatives such as expanding the earth’s forests (afforestation).

According to the report, a half-billion people already live in places turning into desert, and soil is being lost between 10 and 100 times faster than it is being produced.

The hot buttons

1. Human-generated emissions of greenhouse gases are the highest in history. Warming of the climate system is unequivocal: the atmosphere and oceans have warmed, the amounts of snow and ice have diminished, and sea levels have risen. Each of the last three decades has been successively warmer at the Earth’s surface than any preceding decade since 1850. In North America, 1983 to 2012 represented the warmest 30-year period of the last 1,400 years.

2. Half a degree of warming could be the difference between survival and extinction for many species. Biodiversity is threatened.

3. The IPCC report provides a stark profile of transitions required across major sectors of the global economy.

4. Left unchecked, rising temperatures, extreme weather and land degradation could trigger a global food crisis.

5. If average global temperatures rise two degrees Celsius over the pre-industrial average (an arbitrary base-line average between 1850 and 1900), the risk of food supply instabilities from extreme weather events are projected to be very high.

6. The world relies on trade to access food, which increases global vulnerability if food production is affected across several regions at the same time.

7. Domino effect: the probability of major cereal producers facing synchronous shocks is real. Global warming would enable weeds and pests to proliferate and weaken certain crops’ ability to fight disease.

8. The presence of more carbon dioxide in the atmosphere decreases the quality of nutrients in certain crops.

9. Agriculture and other land uses are responsible for about 13 per cent of the carbon dioxide emissions. Deforestation is one of the most significant ways that human land use contributes to global warming.

10. Natural climate solutions alone will not get us where we need to be.

11. The panel’s report outlined possible solutions: more sustainable land management approaches that protect rainforests and wetlands, reducing food waste (estimated to be greater than 30 per cent), widespread adoption of more environmentally friendly diets (veganism or vegetarianism) and eating less red meat.

12. Cattle-rearing generates more global warming greenhouse gases, as measured in CO2 equivalent, than transportation. Smarter production methods, including improved animal diets to reduce enteric fermentation and consequent methane emissions are urgently needed.

13. Livestock is one of the most significant contributors to today’s environmental problems. Cattle-rearing is a major source of land and water degradation (see FAO report, “Livestock’s Long Shadow — Environmental Issues and Options” and CCA/BCRC rebuttal). When emissions from land use and land use change are included, the livestock sector accounts for nine per cent of CO2 (human-related production) and produces 65 per cent of human-related nitrous oxide from manure, which has 296 times the Global Warming Potential (GWP) of CO2; 37 per cent of all human-related methane produced by the digestive system of ruminants (23 times the GWP as CO2); and 64 per cent of ammonia, which contributes significantly to acid rain.

14. With increased prosperity, people are consuming more meat and dairy products every year.

15. The global livestock sector is growing faster than any other agricultural sub-sector. Herds cause wide-scale land degradation, with about 20 per cent of pastures considered degraded through overgrazing, compaction and erosion, contributing to desertification. The livestock business is among the most damaging sectors to the earth’s increasingly scarce water resources, contributing among other things to water pollution from animal wastes, antibiotics and hormones, chemicals from tanneries, fertilizers and the pesticides used to spray feed crops.

16. Humans affect more than 70 per cent of ice-free land — a quarter is already degraded. Today, 500 million people live in areas undergoing desertification and are especially vulnerable to climate change.

17. Plant-based food and fuels are key to initiatives combating climate change.

18. Land is a part of the solution, but land can’t do it all.

19. To say climate change is happening and we will adapt will not work. The capacity to adapt is limited.

20. The global population is set to reach around 10 billion by 2050. There is reason for hope, if immediate action is taken.

Dr. Ron Clarke prepares this column on behalf of the Western Canadian Association of Bovine Practitioners. Suggestions for future articles can be sent to Canadian Cattlemen ([email protected]) or WCABP ([email protected]).

About the author


Dr. Ron Clarke prepares this column on behalf of the Western Canadian Association of Bovine Practitioners. Suggestions for future articles can be sent to Canadian Cattlemen ([email protected]) or WCABP ([email protected]).



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