Lettuce Produces More Greenhouse Gas Emissions Than Bacon Does

A vegetarian diet does not necessarily have a low impact on the environment


Bacon lovers of the world, rejoice! Or at the least take solace that your beloved pork belly may be better for the environment in terms of greenhouse gas emissions than the lettuce that accompanies it on the classic BLT.

This is according to a new study by researchers at Carnegie Mellon University who found that if Americans were to switch their diets to fall in line with the Agriculture Department’s 2010 dietary recommendations, it would result in a 38 percent increase in energy use, 10 percent bump in water use and a 6 percent increase in greenhouse gas emissions.

The reason for this is because on a per-calorie basis, many fruits, vegetables, dairy and seafood—the foods the USDA pushes in the guidelines over sugary processed food and fats—are relatively resource-intensive, the study finds. Lettuce, for example, produces three times more greenhouse gas emissions than bacon.

“You cannot just jump and assume that any vegetarian diet is going to have a low impact on the environment,” said Paul Fischbeck, professor of social and decision sciences and engineering and public policy and one of the authors of the study. “There are many that do, but not all. You can’t treat all fruits and veggies as good for the environment.”

The researchers conducted a meta-analysis of life-cycle assessments quantifying the water, energy use and emissions for more than 100 foods. They found fruits have the largest water and energy footprint per calorie. Meat and seafood have the highest greenhouse gas emissions per calorie.

To create a baseline of how many calories the average adult American consumes, the researchers used weight data provided by the Centers for Disease Control and Prevention and calculated how many calories a person would need to consume in order to maintain that weight. The average calories per day came in at 2,390 per day, or about 200 more than recommended. The researchers tacked on an additional 1,230 calories to account for food waste.

“If what your concern is the greenhouse gas emissions or energy or water use of the entire system, I don’t think you should leave out large chunks of it,” Fischbeck said. “If you want to know how much energy is being consumed, you have to include waste and what is lost from grocery store or dining room table.”

That’s not to say all vegetables are bad. Onions, okra, carrots, broccoli and Brussels sprouts all have decent environmental footprints. Lettuce, on the other hand, is difficult to grow, harvest and transport. It requires significant amounts of water and energy to produce.

“I would eat less lettuce and more Brussels sprouts,” he added.

Some confusing comparisons
Martin Heller, a research specialist with the Center for Sustainable Systems at the University of Michigan and a colleague, published a similar analysis last year. If Americans shifted to following the Agriculture Department’s dietary guidelines, they would consume less meat—good for emissions—but would drink more milk—bad for emissions, the study found (ClimateWire, May 8).

Switching to a lacto-ovo vegetarian diet would result in a 33 percent decrease in emissions. Vegan diets are 53 percent more efficient.

Heller said the Carnegie Mellon paper did a good job of estimating Americans’ daily caloric intake and expanded on his work by quantifying the energy and water impacts of different foods.

But on the bacon-versus-lettuce greenhouse gas emissions showdown, Heller called the comparison “ridiculous.”

“We don’t eat lettuce for its calories,” he said, adding that is why in his food analyses he prefers to do assessments of full diets rather than food-by-food caloric comparisons.

“It’s much easier to compare diets that are different but provide a similar level of nutrition,” he said.

One limitation to all studies that aim to quantify the environmental impacts of human diets is that many of the life-cycle analyses used by researchers are conducted in other countries. In addition, they are often conducted on food commodities, not necessarily the processed products one finds in the grocery store.

The environment likes fats and sugars
To preserve both the Earth’s health and your own, Heller suggests cutting out meat. In the new analysis, beef was 3 ½ times more environmentally intensive than pork. A 2014 Chatham House report found greenhouse gas emissions from the livestock sector are estimated to account for 14.5 percent of the global total, more than direct emissions from the transport sector.

Fischbeck said the takeaway from the analysis is policymakers need to take a closer look at foods on an individual basis, especially as USDA prepares to release its 2015 Dietary Guidelines, expected in a matter of days. These recommendations will guide food purchasing for the federal school lunch program as well as form the basis for federal nutrition policy for the next five years.

Earlier this year, the advisory committee helping to form the recommendations released a report that included environmental impacts in its assessment for the first time (ClimateWire, March 25).

It recommended that Americans adopt a more plant-based diet with plenty of fruits, vegetables, whole grains and legumes. A number of environmentalists and public health experts are hoping to see the considerations included in the official guidelines.

Fischbeck said that even though it seems counterintuitive, the best diet for the environment would be terrible for a person’s health.

“If you totally forget health, which diet would have best impact on the environment?” Fischbeck asked. “You’d eat a lot more fats and sugars.”

The research was published in the journal Environment Systems and Decisions. Co-authors included Michelle Tom and Chris Hendrickson.

*Editor’s Note (12/18/15): The headline of this article was changed to clarify that the comparison between lettuce and bacon is on a “per calorie” basis.

Reprinted from Climatewire with permission from Environment & Energy Publishing, LLC. www.eenews.net, 202-628-6500

Taken by storm: responding to the impacts of climate change


Christian Aid has published a new report detailing the devastating effects of  on some of the poorest communities around the world.

‘Taken by storm: responding to the impacts of climate change’ reveals the way in which developing countries including the Philippines, Brazil, Malawi and Bolivia are suffering the worst consequences, and underlines the need for world leaders to respond with urgency.

It calls for “decisive action to be taken at every opportunity” to combat the disastrous effects.

“Short-term adaptation is not enough. Structural change must come from binding commitments at a global level, and must happen now,” it says.

The report is introduced by Lord Williams, former Archbishop of Canterbury and current Chair of Christian Aid. He recalls the flooding that caused chaos in the UK at the beginning of this year, but notes that though it was highly disruptive and shocking for us in the West, “for millions of people around the world, living with this sense of fragility is nothing new”.

“Far from being a vague threat in the distant future, a warming world is very much a present reality,” he warns. “Stronger storm surges, heavier rain, and scarcer resources are part of what countless people across the world live with daily, with far fewer resources to deal with it than we have.

“It is essential for us to remember the specific human faces of those who suffer because of climate instability. Countless communities and families in every affected region of Africa, Latin America and Asia, people with needs and hopes and anxieties like ours, are already forced to cope with circumstances whose difficulty increases daily, and so with the prospect of an extremely bleak future for themselves and their children if nothing changes.”

The report shares stories of some of the individuals who are suffering as a result of what Lord Williams refers to as this “deep injustice”, as a reminder that there are real people suffering, though we are often blind to it in the West.

Marina Acaylan is one of millions who lost their homes in the devastating typhoon that wreaked havoc across the Philippines last year, killing thousands. She used to earn a living by selling homemade rice cakes at the local market, but can no longer do so because the marketplace was also swept away by the storm.

Kenyan farmers Lilian and Alberty Nthiga are finding it increasingly difficult to grow crops due to a lack of rainfall and thus struggle to make ends meet, while Carmen Quispe Dermarca is having to cope with similar difficulties in Bolivia, where the Illimani glacier is melting.

Although people throughout the developing world are continuing to strive to protect their livelihoods, and are finding ways to cope with changing climates, the report notes that “short-term adaptation is only a temporary fix”.

“The long-term solution will only be found when the global community addresses the root causes of climate change, and takes decisive steps to reduce emissions,” it states.

“There is no doubt that climate change is significantly hampering development work, compounding the many struggles faced by people already fighting to free themselves from poverty’s grip.”

Martin Vilela of Agua Sustentable, a charity working in partnership with Christian Aid in Bolivia to help those struggling with water shortages, says: “We can’t constantly be adapting. I think it’s important that the communities find immediate responses to the changes, but we can’t forget that this is a structural problem.

“[A] key area of our work is to show to the global community the reality of the communities…so they can realise that climate change is real and start to take action to find concrete responses at a global level.

“If this is not achieved, many indigenous peoples’ way of life will be destroyed permanently,” he warns.

Christian Aid’s Senior Climate Change Adviser and author of the report Dr Alison Doig has reiterated the importance of immediate action from the world’s leaders.

“People living on the front line of climate change are the canaries in the climate coalmine, but their plight is more than just a warning of what many other parts of the world can expect,” she said.

“These are individuals paying the price for the actions of wealthy nations and people grown rich through continued dependence on polluting fossil fuels.”

The Intergovernmental Panel on Climate Change (IPCC) is to publish its latest report on the impacts of climate change on Monday, which is expected to make clear the need for strong intervention.

“It is vital that politicians hear their voices and heed the warnings of the IPCC and make tackling climate change a priority if we are to pass on a safe planet fit for future generations,” Doig concludes.

“The world must act decisively and urgently to reduce emissions, manage resources and protect the vulnerable. In this way, and only this way, will we have the chance for a future that is sustainable and fair for the poorest people in the world.”

How can we grow more rice – with less land, water and pollution?


Kritee / Published July 31, 2013 in Economics


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(This post was co-authored by Richie Ahuja.)

Rice feeds the world. It provides more calories to humans than any other food, and more than a billion people depend on rice cultivation for their livelihoods.

In fact, rice is central to existence in many nations. For example, in 2008, when rice prices tripled, the World Bank estimated that an additional 100 million people were pushed into poverty. No wonder that changes in the price and availability of rice have caused social unrest in developing countries.

To keep rice prices affordable as populations increase, the International Rice Research Institute estimates that anadditional 8-10 million tons of rice will need to be produced worldwide every year. But a report from the International Food Policy Research Institute estimates that by 2050 rice prices will increase some 35% because of yield losses due to climate change. Some 90% of the world’s rice is grown in Asia, on more than 200 million small scale farms, most no larger than an acre.

These colliding trends mean that the world must learn to produce more rice – and to do it with less land, less water and less labor. That means devising more efficient and profitable production systems that are resilient to climate change and contribute less to it. This is exactly the challenge EDF and its partners have taken up in India, a country where roughly 500 million of the world’s 2.3 billion people in small-scale farming families live and earn $2 – $4 a day.

Rice farming releases greenhouse gasses more potent than carbon

When organic material decays without oxygen, as it does in water-logged rice paddies, soil microbes generate methane, a greenhouse gas with 25 times more warming potential than CO2. In India, rice methane emission account for about 10% of the nation’s total greenhouse gas (GHG) emissions.

Lately there is growing awareness that when rice is grown under dryer and aerated conditions, nitrous oxide emissions from rice can be as (or even more) significant as methane emissions. Nitrous oxide has about 300 times more warming potential than CO2. It has not yet been estimated what percentage of nitrous oxide emissions in India, or for that matter other rice growing regions in Asia, come from rice cultivation.

Partnering with NGOs in India yields a promising future

The rice farmers in South India are working with non-governmental organizations that are part of a broad coalition called the Fair Climate Network. EDF’s science team is working with these NGOs to develop an environmentally sustainable and economically profitable way to farm rice that will increase climate resilience and decrease GHG emissions.

With our partners, we are developing rice farming practices that change water, fertilizer and organic matter management such that GHG emissions go down as rice yield and farm profitability stay stable or go up. Our partners are working with thousands of rice farmers to record all the farm level data (methods of tilling and weeding, types of fertilizer used, amount of water used and harvest yields) necessary to understand the economic and environmental impacts of their work.

We have also developed protocols to quantify everything: yields, production costs, and emissions of nitrous oxide and methane from the rice fields. Our partners have even set up field laboratories in rural South India to constantly monitor GHG emissions. Our preliminary research work in fields “adopted” by EDF’s partners shows that there is potential to reduce GHG emissions by 2-5 metric tons per acre per year which is same as taking of an average American car off the road for a year.

Eventually, we expect to have enough data to make a case for low carbon farming of rice throughout all of South India. If low carbon rice farming becomes the standard just in all rice growing farms in South Indian states where we are currently active, we can decrease GHG emissions by 40-100 million tons of CO2e per year while saving water, improving farm incomes and protecting rice yields. This reduction is roughly equal to taking 10 million American cars off the road or taking 10-20 coal power plants off the grid. To make this possible, we will have to raise resources for outreach and the transactions costs of monitoring and verifying the GHG reductions.

The potential for this kind of research to support development, food and political security, while mitigating climate change is enormous. That’s something to think about the next time you have a bowl of rice.

Local seeds best bet against climate change



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A paddy field at Pannaikudi in Madurai district. Photo: S. James
The HinduA paddy field at Pannaikudi in Madurai district. Photo: S. James
They need less water, no fertilizer and hardly any care or attention

 has spawned debate as well as initiatives such as planting saplings, cultivating kitchen gardens, household energy conservation and so on.

At the grassroots level, a few farmers are doing their bit to preserve traditional and local varieties of seeds.

“These farmers are commonly called ‘Custodian farmers’. They preserve traditional seeds and make sure that they don’t disappear amongst the variety of hybrid seeds available in the market which farmers prefer because of the promise of high yield,” says M. Palanisamy, Programme Director, Rainfed Farming Development Programme at the Dhan Foundation in Madurai.

The need to preserve traditional and local varieties of seeds that are gradually disappearing is all the more because they do not need much water or chemical fertilizers and pesticides to grow. They can withstand the rigors of climate change and its harsh side effects.

True to the term ‘custodian farmer,’ R. Jeyaraman from Adhirangam in Tiruvarur has preserved 63 types of traditional paddy. “These traditional paddy varieties, unlike the ones used at present, do not need much water,” he explains.

Mr. Jeyaraman has distributed the paddy varieties to farmers from Kerala, Karnataka, Orissa and West Bengal. Among the paddy varieties he has preserved are seeds that need only 60 to 180 days to grow.

“Another factor that most farmers today struggle with is that their crops need constant care and attention, especially before harvest. What they don’t realize is that many of these  need only a short span of time to grow and can be harvested easily,” Mr. Jeyaraman says.

While hybrid varieties enjoy brisk demand, the promise of high yield often diverts attention from the side effects.

“When rainfall is extremely scanty, it is impossible to plant most new varieties of seeds,” A.P. Alagarsamy from Pallapatti in Dindigul district points out.

With climate change affecting the conditions under which these farmers are forced to work, the need for such traditional varieties which can withstand harsh climatic conditions is growing.

“Traditional varieties of paddy that can withstand floods for as long as a month and torrential rain are the kind of seeds we need to preserve,” said Syed Ghani Khan, a farmer from Mandya in Karnataka.

“With traditional paddy types from Thailand, Burma and Indonesia, I hope to preserve many more traditional seeds through cross pollination,” he adds.

Hybrid seeds and the other varieties that are distributed also have a shorter lifespan that results in the quantity of yield gradually decreasing as years go by.

“Seeds from the hybrid crops cannot be sown directly. The farmer is forced to go back to the centres after his crop is harvested to buy the seeds again and has no control over the price,” says Mr. Palanisamy.

Jegannath Raja from Rajapalayam district has preserved and aggressively marketed two varieties of mango — ‘Mohandas’ and ‘Potllama.’

“The two traditional varieties are fast disappearing and I managed to preserve them and spread awareness of how these varieties can be used to generate income in rain-starved areas since they do not need much water to grow,” says Mr. Jegannath.

He has preserved over 2,000 traditional varieties of fruit, though not all are income-generating.

“While I have preserved a number of seeds to safeguard them, I encourage farmers to buy only a few varieties that are traditional and promise high yield,” he says.

With the importance of preservation and conservation of these traditional and indigenous seeds, there is a need for live genetic resources or nurseries to facilitate studies and spread awareness among farmers.

“Farmers should set apart a portion of their land for cultivation of traditional seeds. With live genetic resources, or maintaining nurseries rather than seeds, it will be easier for farmers to choose varieties and see the benefits for themselves,” said R. Adinarayanan, a faculty member at the Tata Dhan Academy.

The farmers were recently honoured at the Madurai Symposium 2013, organized by the Dhan Academy, and given the ‘Custodian Farmer’ awards for their contribution to biodiversity conservation.

“God has given us the resources we are using now and it is our duty to conserve them and pass them on to posterity,” says Mr. Syed Ghani.

Wake up before it is too late: Make agriculture truly sustainable now for food security in a changing climate


Developing and developed countries alike need a paradigm shift in agricultural development: from a “green revolution” to a “truly ecological intensification” approach. This implies a rapid and significant shift from conventional, monoculture-based and high external-input-dependent industrial production towards mosaics of sustainable, regenerative production systems that also considerably improve the productivity of small-scale farmers. We need to see a move from a linear to a holistic approach in agricultural management, which recognizes that a farmer is not only a producer of agricultural goods, but also a manager of an agro-ecological system that provides quite a number of public goods and services (e.g. water, soil, landscape, energy, biodiversity, and recreation) UNCTAD’s Trade and Environment Review 2013 (TER13) contends.

TER13 highlights that the required transformation is much more profound than simply tweaking the existing industrial agricultural system. Rather, what is called for is a better understanding of the multi-functionality of agriculture, its pivotal importance for pro-poor rural development and the significant role it can play in dealing with resource scarcities and in mitigating and adapting to climate change. However, the sheer scale at which modified production methods would have to be adopted, the significant governance issues, the power asymmetries’ problems in food input and output markets as well as the current trade rules for agriculture pose considerable challenges.

TER13, entitled Wake up Before it is Too Late: Make Agriculture Truly Sustainable Now for Food Security in a Changing Climate was released on 18 September 2013. More than 60 international experts have contributed their views to a comprehensive analysis of the challenges and the most suitable strategic approaches for dealing holistically with the inter-related problems of hunger and poverty, rural livelihoods, social and gender inequity, poor health and nutrition, and climate change and environmental sustainability – one of the most interesting and challenging subjects of present development discourse.

Agricultural development, the report underlines, is at a true crossroads. By way of illustration, food prices in the period 2011 to mid-2013 were almost 80% higher than for the period 2003-2008. Global fertilizer use increased by 8 times in the past 40 years, although global cereal production has scarcely doubled at the same time. The growth rates of agricultural productivity have recently declined from 2% to below 1% per annum. The two global environmental limits that have already been crossed (nitrogen contamination of soils and waters and biodiversity loss) were caused by agriculture. GHG emissions from agriculture are not only the single biggest source of global warming in the South, besides the transport sector, they are also the most dynamic. The scale of foreign land acquisitions (often also termed land grabbing) dwarfs the level of Official Development Assistance, the former being 5-10 times higher in value than the latter in recent years.

Most important of all, despite the fact that the world currently already produces sufficient calories per head to feed a global population of 12-14 billion, hunger has remained a key challenge. Almost one billion people chronically suffer from starvation and another billion are mal-nourished. Some 70% of these people are themselves small farmers or agricultural laborers. Therefore, hunger and mal-nutrition are not phenomena of insufficient physical supply, but results of prevailing poverty, and above all problems of access to food. Enabling these people to become food self-sufficient or earn an appropriate income through agriculture to buy food needs to take center stage in future agricultural transformation. Furthermore, the current demand trends for excessive biofuel and concentrate animal feed use of cereals and oil seeds, much too high meat-based diets and post-harvest food waste are regarded as given, rather than challenging their rational. Questionably, priority in international policy discussions remains heavily focused on increasing industrial agricultural production, mostly under the slogan “growing more food at less cost to the environment”.

The strategy recommended to developing countries of relying on international markets to meet staple food demand, while specializing in the production and export of ‘lucrative’ cash crops has not produced the intended results, because it relied on low staple food prices and no shortage of supply in international markets, conditions that have drastically changed since the turn of the century. Globalization has also encouraged excessive specialization, increasing scale of production of few crops and enormous cost pressure. All this has aggravated the environmental crisis of agriculture and reduced agricultural resilience. What is now required is a shift towards diverse production patterns that reflect the multi-functionality of agriculture and enhance close nutrient cycles. Moreover, as environmental externalities are mainly not internalized, carbon taxes are the rare exception rather than the rule and carbon-offset markets are largely dysfunctional – all factors that would prioritize regional/local food production through ‘logical’ market mechanisms – trade rules need to allow a higher regional focus of agriculture along the lines of “as much regionalized/localized food production as possible; as much traded food as necessary”.

Climate change will drastically impact agriculture, primarily in those developing countries with the highest future population growth, i.e. in sub-Saharan Africa and South Asia. Against this background, the fundamental transformation of agriculture may well turn out to be one of the biggest challenges, including for international security, of the 21st century. Much slower agricultural productivity growth in the future, a quickly rising population in the most resource-constrained and climate-change-exposed regions and a burgeoning environmental crises of agriculture are the seeds for mounting pressures on food security and the related access to land and water. This is bound to increase the frequency and severity of riots, caused by food-price hikes, with concomitant political instability, and international tension, linked to resource conflicts and migratory movements of starving populations.

Turn down the heat : climate extremes, regional impacts, and the case for resilience – full report (English)


This report focuses on the risks of climate change to development in Sub-Saharan Africa, South East Asia and South Asia. Building on the 2012 report, Turn Down the Heat: Why a 4°C Warmer World Must be Avoided, this new scientific analysis examines the likely impacts of present day, 2°C and 4°C warming on agricultural production, water resources, and coastal vulnerability for affected populations. It finds many significant climate and development impacts are already being felt in some regions, and in some cases multiple threats of increasing extreme heat waves, sea level rise, more severe storms, droughts and floods are expected to have further severe negative implications for the poorest. Climate related extreme events could push households below the poverty trap threshold. High temperature extremes appear likely to affect yields of rice, wheat, maize and other important crops, adversely affecting food security. Promoting economic growth and the eradication of poverty and inequality will thus be an increasingly challenging task under future climate change. Immediate steps are needed to help countries adapt to the risks already locked in at current levels of 0.8°C warming, but with ambitious global action to drastically reduce greenhouse gas emissions, many of the worst projected climate impacts could still be avoided by holding warming below 2°C.