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THE FIRST OF TWO PARTS. Followup story is at: http://www.sciencenews.org/view/generic/id/40943/title/AAAS_Climate-Friendly_Fish
For the good of the planet, we’re all being asked to reduce our carbon footprints — the quantities of greenhouse gases, aka GHGs, associated with our actions. Since some 30 percent of the global warming potential attributable to society’s GHG emissions stems from the production of foods and beverages, menu choices are critical, noted Ulf Sonesson of the Swedish Institute for Food and Biotechnology in Goteborg, today. From this climate perspective, meat eaters are the big hogs.
Sonesson was one of the speakers on a panel titled “Food for Thought” at the American Association for the Advancement of Science annual meeting. This morning’s speakers shared data from largely new analyses on how foods, production techniques, and transportation affect the climate costs associated with our dining choices. And there were some big surprises.
No longer a surprise is the relative energy intensity associated with meat, especially beef. For instance, roughly half of the GHG emissions due to human diets come from meat even though beef, pork and chicken together account for only about 14 percent of what people eat.
From a climate perspective, beef is in a class by itself. It takes a lot of energy and other natural resources to produce cattle feed, manage the animals’ manure (a major emitter of methane, a potent GHG), get the livestock to market, slaughter the animals, process and package the meat, dispose of the greater part of the carcass that won’t be human food, market the retail cuts, transport them home from the store, refrigerate them until dinner time, and then cook the beef.
Tally the GHG emissions associated with all of those activities, Sonesson says, and you’ll find it’s the global-warming equivalent to spewing 19 kilograms of carbon dioxide for every kg of beef served. Swine are more environmentally friendly. It only takes about 4.25 kg of CO2 to produce and fry each kg of pork. At the other end of the spectrum are veggies. The climate costs associated with growing, marketing, peeling and boiling up a kg of potatoes, by contrast, is just 280 grams, Sonesson reported.
Another factor contributing to cattle’s particularly egregious carbon footprint is their relative fecundity, if you will, says Nathan Pelletier of Dalhousie University in Halifax, Nova Scotia. In her lifetime, a mother fish, particularly in protected aquaculture settings, may give birth to hundreds — if not thousands — of surviving offspring. A hen could certainly produce hundreds of chicks. Even a sow can give birth to eight piggies per litter. But a cow: She tends to issue a single calf every year for maybe 10. And while she’s in gestation and then waiting to become pregnant again, farmers have to care for her and perhaps a bull — which are both big, hungry manure factories.
Many environmentalists have argued that finishing up the fattening of beef cattle on corn is worse for the environment than cattle that are raised solely on pasture grass. Pelletier says his team’s analysis finds that at least from a climate perspective, the opposite is true. “We do see significant differences in the GHG intensities [of grass vs grain finishing]. It’s roughly on the order of 50 percent higher in grass-finished systems.”
When an audience member questioned whether he had heard that right, that grass-fed cattle have a higher carbon footprint, Pelletier reiterated, “higher. Yes.” The reason: “It’s related to the much higher volumes of feed throughput and associated methane and nitrous-oxide [GHG] emissions.” He added that most pastures were highly managed, and subject to “periodic renovations and also fertilization.” Finally, with grass-fed cattle “there is also a high [grass] trampling rate. So the actual land area that you need to maintain magnifies that [GHG] difference,” Pelletier said.
But what really concerns his team about the bonus GHG emissions linked to beef is the planet’s growing numbers — and appetite for meat.
Currently, although beef accounts for only about 30 percent of the industrial world’s meat consumption, it contributes 78 percent meat’s GHG emissions there. Pork, at 38 percent of consumption, contributes only 14 percent of this meat's GHGs. Another 32 percent of the meat consumed worldwide comes from chicken, but getting these birds from farm to fork contributes only 8 percent of meat’s carbon footprint in the developed countries. By shifting some share of beef and pork production to chicken over the next four decades, the increase in meat’s GHG emissions by 2050 might be held to just 6 percent higher than today in the developed world, Pelletier said, even as the human population grows by another quarter-million each day.
Although meat's overall carbon footprint is projected to grow only a little over the next 40 years within industrialized countries, the global goal is to cut emissions in every sector. Pelletier offered some suggestions on how to do that. Some were considerably more appetizing than others.
For instance, substituting all beef production for chicken would cut meat’s projected carbon footprint by 70 percent, he said. Or perhaps per capita intake of meat could drop from a current average of 90 kilograms per year in the developed world to the 53 kg per person per year that's been advocated as sufficient for human health by the U.S. Department of Agriculture. Under this scenario, Pelletier said, “I estimate that . . . we could reduce associated [carbon] emissions by roughly 44 percent.”
Swap half of that protein now supplied by meat with soy by 2050, and “you could expect [projected] emissions to decrease on the order of 70 percent,” he said. Take the next big step — eliminating all meat in favor of soy — should drop the protein-associated carbon footprint of Western diets a whopping 96 percent.
Pelletier described that the last scenario as “utopian.” Hmmm. Not for this carnivore. I’m willing to eat chicken much of the time and reserve beef as a big treat — maybe even to be downed only in small portions. But go solely soy? That’s no utopia to me.
That said, would I consider such a sacrifice for survival of the planet? Of course — but I’m hoping someone can shoot me recipes that would made this legume taste like something other than soy. So far I only have one, but it's dynamite: for chocolate mousse pie.
Next up: What about fish?
Found in: Agriculture, Climate Change, Environment, Food Science, Matter & Energy, Nutrition and Science & Society
- It’s the meat not the miles
- Science & the Public : The Costs of Meat and Fish
- A Thirst for Meat: Changes in diet, rising population may strain China's water supply
- Food for Thought : The Short and Long of the Food Transport Story
- Science & the Public : AAAS: Climate-friendly fish
- Sonesson, U. 2009. The Secret Life (Cycle) of Foods. American Association for the Advancement of Science annual meeting, Chicago (Feb. 15).
- Pelletier, N. 2009. Neither Fish Nor Fowl — Planning Dinner Around the Carbon Intensity of Protein Sources. American Association for the Advancement of Science annual meeting, Chicago (Feb. 15).
- Science & the Public : GNP’s glaciers: Going, going . . .
- Science & the Public : Insurance payouts point to climate change
- Science & the Public : Bush meat can be a viral feast
- On the Scene : Vying for the title of World's Fastest Cell
- Deleted Scenes : Moony shot
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See the comments on my post--our readers are taking issue with the assertion than soy products (particularly processed soy products such as soy burgers, but also soy beans grown by huge factory farms) are more environmentally friendly than meat (particularly grass-fed meat from small, local farms). It seems as if there's a lot of confusion and conflicting information when it comes to adding up all the factors that make an item "environmentally friendly" or not. I'd love to get an additional comment from you or from Ulf Sonesson on this subject--feel free to comment on my blog post if you'd like to weigh in further. Thanks so much, Sarah Kagan
Of course there are ways that beef production could be made much more environmentally benign, but to say that other sources of protein -- soy, poultry, and swine, which all rely exclusively on tillage of soil for their production -- are smaller emitters of carbon than a cow living on pasture or range really taxes the credulity.
The mere act of exposing soil to the air releases carbon. The fact that swine and poultry must be fed grains most of their lives means that they are responsible for a great deal of land being turned over. They are better converters of the product of this tillage into human-digestible protein than beef are, but there is no point in their lifecycle where they are actually building organic matter -- mostly carbon -- in the soils that support them.
I don't know, but I would wager than consuming grass-fed beef, which eliminates the carbon-spewing feedlot from the equation, grown within the standard localvore 100-mile circle, eliminating a lot of the transportation-related emissions, would be a net sequestration of carbon, not an emission.
Here in San Francisco Bay area and in much of California, very little ranching occurs on irrigated and fertilized pastures - it's mostly up in the hills.
Soil exposure and CO2 release from trampling due to bad management is an interesting point. On the other hand, good ranching reduces fire risk relative to no ranching, so CO2 stays in the soil longer than in the air with a quick fire return cycle.
Devil's in the details.
Grass fed beef raise with good farming practices can be CHG neutral or reduce CHG. See: Grass Farming benefits to the environment at [Link was removed]
I think Pelletier's research must have only looked at industrial railsed cattle.
Here are some vegan recipe sites specifically for holidays: [Link was removed]
Hundreds of recipes are here: [Link was removed]
The UN IPCC considers methane to be 23 TIMES as powerful a GHG than CO2, so each unit of methane counts as 23 units of CO2. Cattle eating grass produce about twice as much methane as cattle eating corn -- partly because it takes longer for grass-fed cattle to reach market weight, but mostly because the rumen bacteria create far more by-product methane when breaking down resistant cellulose (grass) than when breaking down starch (corn).
When all is said and done, the larger amount of 23X more powerful methane overwhelms the larger CO2 emissions from corn production, resulting in 40-50% higher CO2-equivalent GHG emissions from grass-fed cattle (per pound of meat produced). My report shows this in detail ( [Link was removed] ) but even the UN quietly acknowledges this in its own report, Livestock's Long Shadow. Here are two little known quotes from that report:
“. . . by far the largest share of emissions come from more extensive systems.” [i.e. organic grass-fed systems]
–“The most promising approach for reducing methane emissions from livestock is by improving [the productivity and efficiency] of livestock production. . . . The basic principle is to increase the digestibility of feedstuff.”
This report is the condense version. This report proves green house gases are not responsible for global warming. My purpose is to gain support for this report. Global warming-the apocalypse can be stopped, with your help. If not stopped the sun’s heat will dominate this planet’s weather, and generate unusual weather patterns, to the point where the only thing to eat will be other people. The real reason for global warming is the earth’s orbit around the sun is decaying, in other words the earth is moving closer to the sun. The earth is a planet that functions like a machine. In fact It’s more like a machine, than a planet. Like a car, truck, aircraft, or rocket. The earth has a fuel system, an engine, a generator, and exhaust system. A car’s engine system generates torque, an aircraft’s engine systems generates thrust, and the earth’s engine system generates a powerful magnetic field, and the earth’s magnetic field protects all life on this planet, and beneath the oceans. The earth’ magnetic field keeps the earth at a safe distance from the sun, and the core is the earth’s engine earth’s fuel system is referred to as oil wells/ crude oil reservoirs. They are actually self pressurizing fuel cells. Like any machine, if you were to shut off fuel to the engine, the engine will stop operating. The oil company’s crude oil extraction process compromises the earth’s fuel system, and shut off fuel to the earth’s engine (the core), by releasing pressure out of the earth’s fuel system (oil wells). Normally the pressure in a crude oil well/ reservoir is tens of thousands to hundreds of thousands of pounds per square inch. Under normal circumstance the core (the engine) stays at a constant 5000 to 7000 degrees celsius, and that’s hot enough to melt steel, and the pressure in the core is tens of thousands to hundreds of pounds per square inch. The oil is ignited long before it reaches the core, and enters the core as flames. Crude oil a hydrocarbon is capable of generating those temperatures in the core. Hydrocarbons are used to melt, and manufacture steel. The higher the temperature in the core, and the stronger the earth’s magnetic field. The cooler the core, the weaker the earth’s magnetic field. The earth’s engine is being fuel starved, and it is slowly cooling. As the core cools the earth’s magnetic field weakens, and the earth is being pulled closer to the sun Global Warming has nothing to do with green house gases, holes in the ozone, CFC, R-12 refrigerant, and aerosol propellant, etc. The only way to reverse global warming-the apocalypse is for the oil companies to re-pressurize the earth’s fuel systems. One way this can be accomplished, by igniting the methane gas in them. The ignited gas will expand, and create the pressure need to force the remaining crude oil (fuel) into the core. This is the real cause for global warming, and the only way it can be reversed. Volcanoes are the earth’s exhaust system. Volcanoes are designed to rid the core (the earth’s engine) of spent fuel, debris, and they regulate the pressure in the core, which is generated by the combustion of crude oil. The pressure that’s release from volcanoes is provided by carbon dioxide, nitrogen, sulphur dioxide, carbon monoxide, and these are all crude oil by-product. These gases prove crude oil is being burned in the core. The earth, and conditions on it are changing, and not for the better. 12 noon use to be the hottest part of the day, now it 3 o’clock in the after noon. The winters are getting sunny, and warmer from latitude (zero) to latitude (29.0- N, and 29.0- S), during winter. Both polar ice caps are melting, and the oceans are rising. The earth has shifted on it’s axes by15 degrees. The earth is moving away from the moon 4 cm each year, and the distance have increase by 220,000 miles over the decades. Floods, and tornadoes are developing in winter, from latitude (29.0 -N) to latitude (35.28 N), and higher latitudes. Two leap seconds had to be added to the atomic clock, because the earth rotation is slowing down. It’s getting noticeably hotter every 15 to 20 years. Our grand children are in grave danger!
Written by: Willie McDonald: cdnld30@gmail.com: 832-889-2058. Copyright-2008
Regardless, it just makes sense to limit one's consumption of meat. I'm still an omnivore, I'm not a fan of soy and I eat between 2 and 8 oz of meat (including fish) a week. It's a lot less than the 22 oz beef steaks I've seen on the menu at some restaurants!
Instead, I eat lots of combinations of beans, grains, vegetables, nuts, and mushrooms plus the occasional egg, serving of goat's milk cheese, and servings of various cow's milk dairy products. The milk of one cow can feed *a lot* of people! When I've spent the time to document everything I eat in a week, I get quite enough protein without eating much meat.
If we all stuck to the 53 kg of meat per person per year recommended by the USDA, that works out to 5 oz a day, if I did the conversions right. It's slightly more meat than a McD's quarter-pounder hamburger, which is already too much meat and fat anyway.
BTW, the chocolate mousse pie link isn't working just now.
But the point is: you don't have to be a fan of soy to limit your consumption of meat, while still enjoying some meat and while getting enough protein. As Helen Nearing wisely points out in "Simple Food for the good life," meat is just something people began to eat when they couldn't get fresh vegetables. It's true of dairy too.
Raw Forbidden Rice Pineapple Smoothie
1 15 once bag Organic Forbidden Rice
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1 or 2 pineapple(s)
Enough water to keep the rice covered.
An ice crushing 0.9HP $120 0.9 HP blender from Target similar to [Link was removed] +KSB560WH or better.
This recipe is easiest with the “2 peak HP” blenders from Vita-Mix [Link was removed] .
An older $60 blender from Target wasn’t up to the job.
Cover the rice with water and soak in the refrigerator for at least 12 hours.
Drain the rice, save the water.
Blend the rice with as little saved water as possible at high speed with a good funnel for at least 2 minutes. On my blender I did 1/3rd of the rice at a time.
Blend the pineapple(s) at high speed for at least 1 minute.
Thoroughly mix the rice and pineapple. I sectioned through my blender.
Seal the rice – pineapple mixture in a container.
To give time for the Bromelain Enzyme [Link was removed] in the pineapple to “cook” the rice either rest the mixture on the countertop at room temperature for 4 hours or in the refrigerator for 12 hours.
Pour the mixture into ice trays and freeze. My freezer took about 8 hours.
Using as little of the saved water as possible section the rice-pineapple frozen cubes through the blender.
I have also made the recipe with 1 pineapple and 1 package of frozen açai juice instead of 1 or 2 pineapples.
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