Meat, diet and climate change- recent peer reviewed studies and perspectives

 

Eating less meat might not be the way to go green, say researchers

January 19 2016

R. de Oliveira Silva, L. G. Barioni, J. A. J. Hall, M. Folegatti Matsuura, T. Zanett Albertini, F. A. Fernandes, D. Moran. Increasing beef production could lower greenhouse gas emissions in Brazil if decoupled from deforestation. Nature Climate Change, 2016; DOI: 10.1038/nclimate2916

Reduced meat consumption might not lower greenhouse gas emissions from one of the world’s biggest beef producing regions, new research has found. The finding may seem incongruous, as intensive agriculture is responsible for such a large proportion of global greenhouse gas emissions. According to research by University of Edinburgh, Scotland’s Rural College (SRUC) and Brazilian Agricultural Research Corporation (Embrapa), reducing beef production in the Brazilian Cerrado could actually increase global greenhouse gas emissions. The findings were published in the journal Nature Climate Change.

Lead author Rafael Silva, of the University of Edinburgh’s School of Mathematics, explains: “Much of Brazil’s grassland is in poor condition, leading to low beef productivity and high greenhouse gas emissions from cattle. However, increasing demand for meat provides an incentive for farmers to recover degraded pastures. This would boost the amount of carbon stored in the soil and increase cattle productivity. It would require less land for grazing and reduce deforestation, potentially lowering emissions.” While grasslands are not as effective as forests at storing carbon, Brazilian grass — mostly Brachiaria genus — has a greater capacity to do so than grass found in Europe, due to its long roots. High quality grasslands will cause more carbon to be stored in the soil, which will lead to a decrease in CO2 emissions. Grassland improvement involves chemical and mechanical treatment of the soil, and use of better adapted seeds along with calcium, limestone and nitrogen fertilisers. Most Brazilian grassland soils are acidic, requiring little nitrogen.

In the case of the Brazilian Cerrado, reduced meat consumption could remove the incentive for grassland improvement and therefore lead to higher emissions. The researchers worked out that if demand for beef is 30% higher by 2030 compared with current estimates, net emissions would decrease by 10%. Reducing demand by 30% would lead to 9% higher emissions, provided the deforestation rates are not altered by a higher demand. However, if deforestation rates increase along with demand, emissions could increase by as much as 60%….

 

Vegetarian and ‘healthy’ diets could be more harmful to the environment, researchers say

December 14, 2015

Michelle S. Tom, Paul S. Fischbeck, Chris T. Hendrickson. Energy use, blue water footprint, and greenhouse gas emissions for current food consumption patterns and dietary recommendations in the US. Environment Systems and Decisions, 2015; DOI: 10.1007/s10669-015-9577-y

 

….Specifically, they examined how growing, processing and transporting food, food sales and service, and household storage and use take a toll on resources in the form of energy use, water use and GHG emissions.

On one hand, the results showed that getting our weight under control and eating fewer calories, has a positive effect on the environment and reduces energy use, water use and GHG emissions from the food supply chain by approximately 9 percent.

However, eating the recommended “healthier” foods — a mix of fruits, vegetables, dairy and seafood — increased the environmental impact in all three categories: Energy use went up by 38 percent, water use by 10 percent and GHG emissions by 6 percent.

“There’s a complex relationship between diet and the environment,” Tom said. “What is good for us health-wise isn’t always what’s best for the environment. That’s important for public officials to know and for them to be cognizant of these tradeoffs as they develop or continue to develop dietary guidelines in the future.”

 

Changing global diets is vital to reducing climate change, researchers say

August 31, 2014

Bojana Bajželj, Keith S. Richards, Julian M. Allwood, Pete Smith, John S. Dennis, Elizabeth Curmi, Christopher A. Gilligan. Importance of food-demand management for climate mitigation. Nature Climate Change, 2014; DOI: 10.1038/nclimate2353

Healthier diets and reducing food waste are part of a combination of solutions needed to ensure food security and avoid dangerous climate change, say the team behind a new study.

A new study, published today in Nature Climate Change, suggests that — if current trends continue — food production alone will reach, if not exceed, the global targets for total greenhouse gas (GHG) emissions in 2050.

The study’s authors say we should all think carefully about the food we choose and its environmental impact. A shift to healthier diets across the world is just one of a number of actions that need to be taken to avoid dangerous climate change and ensure there is enough food for all.

As populations rise and global tastes shift towards meat-heavy Western diets, increasing agricultural yields will not meet projected food demands of what is expected to be 9.6 billion people — making it necessary to bring more land into cultivation.

This will come at a high price, warn the authors, as the deforestation will increase carbon emissions as well as biodiversity loss, and increased livestock production will raise methane levels. They argue that current food demand trends must change through reducing waste and encouraging balanced diets.

If we maintain ‘business as usual’, say the authors, then by 2050 cropland will have expanded by 42% and fertiliser use increased sharply by 45% over 2009 levels. A further tenth of the world’s pristine tropical forests would disappear over the next 35 years.

The study shows that increased deforestation, fertilizer use and livestock methane emissions are likely to cause GHG from food production to increase by almost 80%. This will put emissions from food production alone roughly equal to the target greenhouse gas emissions in 2050 for the entire global economy.

The study’s authors write that halving the amount of food waste and managing demand for particularly environmentally-damaging food products by changing global diets should be key aims that, if achieved, might mitigate some of the greenhouse gases causing climate change.

“There are basic laws of biophysics that we cannot evade,” said lead researcher Bojana Bajzelj from the University of Cambridge’s Department of Engineering, who authored the study with colleagues from Cambridge’s departments of Geography and Plant Sciences as well as the University of Aberdeen’s Institute of Biological and Environmental Sciences.

“The average efficiency of livestock converting plant feed to meat is less than 3%, and as we eat more meat, more arable cultivation is turned over to producing feedstock for animals that provide meat for humans. The losses at each stage are large, and as humans globally eat more and more meat, conversion from plants to food becomes less and less efficient, driving agricultural expansion and land cover conversion, and releasing more greenhouse gases. Agricultural practices are not necessarily at fault here — but our choice of food is,” said Bajzelj….

 

Meat food waste has greater negative environmental impact than vegetable waste

August 14, 2015

Christine Costello, Esma Birisci, Ronald G. McGarvey. Food waste in campus dining operations: Inventory of pre- and post-consumer mass by food category, and estimation of embodied greenhouse gas emissions. Renewable Agriculture and Food Systems, 2015; 1 DOI: 10.1017/S1742170515000071

 

Approximately 31 percent of food produced in the U.S., or 133 billion pounds of food worth $162 billion, was wasted in 2011 according to the United States Department of Agriculture (USDA). Now, University of Missouri researchers have found that the type of food wasted has a significant impact on the environment. Although less meat is wasted (on average) compared to fruits and vegetables, the researchers found that significantly more energy is used in the production of meat compared to the production of vegetables. This wasted energy is usually in the form of resources that can have negative impacts on the surrounding environment, such as diesel fuel or fertilizer being released into the environment.

“While many of us are concerned about food waste, we also need to consider the resources that are wasted when we throw away edible food,” said Christine Costello, assistant research professor at the College of Agriculture, Food and Natural Resources and co-author of the study. “Farm equipment used to feed and maintain livestock and plant and harvest crops uses a lot of diesel fuel and other utilities from fossil fuels. When people waste meat, these fuels, as well as fertilizers, are also wasted. Based on our study, we recommend that people and institutions be more conscious of not only the amount but the types of food being wasted.”

During the study, pre- and post-consumer food waste was collected from four all-you-care-to-eat dining facilities over three months in 2014. Costello and her research team created a detailed inventory of the specific types of food waste: meat, vegetables or starches. The food waste also was categorized as either edible or inedible (peels and ends of fruits and vegetables).

Once the food waste was categorized, Costello and her research team analyzed greenhouse gas (GHG) emissions resulting from fertilizer use, vehicle transportation, and utility use on the farm. GHG emission estimates were measured from cradle (land preparation or animal birth) to farm gate (when the grain or animal was sent to a processing facility). Previous studies have shown that the majority of GHG emissions occur in the production stages prior to the farm products’ leaving the farm.

“Based on the findings, we recommend consumers pay special attention to avoiding waste when purchasing and preparing meat; if consumers choose to prepare extra food ‘just in case,’ they should use plant-based foods,” said co-author Ronald G. McGarvey, assistant professor at the Harry S Truman School of Public Affairs and Department of Industrial and Manufacturing Systems Engineering.

 

 

Eating less meat: Solution to reduce water use?

August 4, 2014

M Jalava, M Kummu, M Porkka, S Siebert, O Varis. Diet change—a solution to reduce water use?
Environmental Research Letters, 2014; 9 (7): 074016 DOI: 10.1088/1748-9326/9/7/074016

Eating less meat would protect water resources in dry areas around the world, researchers at Aalto University have found.

Reducing the use of animal products can have a considerable impact on areas suffering scarce water resources, as meat production requires more water than other agricultural products.

“Diet change together with other actions, such as reduction of food losses and waste, may tackle the future challenges of food security,” states researcher Mika Jalava from Aalto University.

Growing population and climate change are likely to increase the pressure on already limited water resources and diet change has been suggested as one of the measures contributing to adequate food security for growing population.

The researchers assessed the impact of diet change on global water resources over four scenarios, where the meat consumption was gradually reduced while diet recommendations in terms of energy supply, proteins and fat were followed. The study published in Environmental Research Letters is the first global-scale analysis with a focus on changes in national diets and their impact on the blue and green water use of food consumption.

Food supply for growing population

Global population is expected to exceed 9 billion by 2050, adding over 2 billion mouths to be fed to the current population, according to the UN. By reducing the animal product contribution in the diet, global green water (rainwater) consumption decreases up to 21 % while for blue water (irrigation water) the reductions would be up to 14 %. In other words, by shifting to vegetarian diet we could secure adequate food supply for an additional 1.8 billion people without increasing the use of water resources. The potential savings are, however, distributed unevenly, and even more important, their potential alleviation on water scarcity varies widely from country to country….

 

Climate: Meat turns up the heat as livestock emit greenhouse gases

July 21, 2014

Dario Caro, Steven J. Davis, Simone Bastianoni, Ken Caldeira. Global and regional trends in greenhouse gas emissions from livestock. Climatic Change, 2014; DOI: 10.1007/s10584-014-1197-x

Eating meat contributes to climate change, due to greenhouse gasses emitted by livestock. New research finds that livestock emissions are on the rise and that beef cattle are responsible for far more greenhouse gas emissions than other types of animals. It is published by Climatic Change. Carbon dioxide is the most-prevalent gas when it comes to climate change. It is released by vehicles, industry, and forest removal and comprises the greatest portion of greenhouse gas totals. But methane and nitrous oxide are also greenhouse gasses and account for approximately 28 percent of global warming activity.

Methane and nitrous oxide are released, in part, by livestock. Animals release methane as a result of microorganisms that are involved in their digestive processes and nitrous oxide from decomposing manure. These two gasses are responsible for a quarter of these non-carbon dioxide gas emissions and 9 percent of total greenhouse gas emissions overall.

 

Vegetarian diets produce fewer greenhouse gases and increase longevity, say new studies

June 25, 2014

1. S. Soret, A. Mejia, M. Batech, K. Jaceldo-Siegl, H. Harwatt, J. Sabate. Climate change mitigation and health effects of varied dietary patterns in real-life settings throughout North America. American Journal of Clinical Nutrition, 2014; 100 (Supplement_1): 490S DOI: 10.3945/ajcn.113.071589
2. J. Sabate, S. Soret. Sustainability of plant-based diets: back to the future. American Journal of Clinical Nutrition, 2014; 100 (Supplement_1): 476S DOI: 10.3945/ajcn.113.071522

Consuming a plant-based diet results in a more sustainable environment and reduces greenhouse gas emissions, while improving longevity, according to new research from Loma Linda University Health.

A study and an article, produced by researchers at Loma Linda University School of Public Health, will be published in full in the July issue of the American Journal of Clinical Nutrition, and were first presented at the 6th International Congress on Vegetarian Nutrition in 2013.

Based on findings that identified food systems as a significant contributor to global warming, the study focuses on the dietary patterns of vegetarians, semi-vegetarians and non-vegetarians to quantify and compare greenhouse gas emissions, as well as assess total mortality.

The mortality rate for non-vegetarians was almost 20 percent higher than that for vegetarians and semi-vegetarians. On top of lower mortality rates, switching from non-vegetarian diets to vegetarian diets or even semi-vegetarian diets also helps reduce greenhouse gas emissions. The vegetarian diets resulted in almost a third less emissions compared to the non-vegetarian diets. Modifying the consumption of animal-based foods can therefore be a feasible and effective tool for climate change mitigation and public health improvements, the study concluded.

“The takeaway message is that relatively small reductions in the consumption of animal products result in non-trivial environmental benefits and health benefits,” said Sam Soret, Ph.D., MPH, associate dean at Loma Linda University School of Public Health and co-author of the studies.

The study drew data from the Adventist Health Study, which is a large-scale study of the nutritional habits and practices of more than 96,000 Seventh-day Adventists throughout the United States and Canada. The study population is multi-ethnic and geographically diverse.

 

Nitrogen pollution, climate and land use: Why what we eat matters

April 25, 2014

Henk Westhoek, Jan Peter Lesschen, Trudy Rood, Susanne Wagner, Alessandra De Marco, Donal Murphy-Bokern, Adrian Leip, Hans van Grinsven, Mark A. Sutton, Oene Oenema. Food choices, health and environment: Effects of cutting Europe’s meat and dairy intake. Global Environmental Change, 2014; DOI: 10.1016/j.gloenvcha.2014.02.004

 

A new report quantifies for the first time how much our food choices affect pollutant nitrogen emissions, climate change and land-use across Europe.

The executive summary of the European Nitrogen Assessment Special Report on Nitrogen and Food, ‘Nitrogen on the Table’, was released today (Friday 25 April 2014). The Special report provides an assessment of what would happen if Europe were to decrease its consumption of meat and dairy products. It shows how much cutting down on meat and dairy in our diets would reduce nitrogen air and water pollution, and greenhouse gas emissions, while freeing up large areas of farmland for other purposes such as food export or bioenergy. It also considers the health benefits of reduced meat consumption. The full report is published next month.

Report lead author Henk Westhoek, program manager for Agriculture and Food at PBL (the Netherlands Environmental Assessment Agency) said, “The report shows that the nitrogen footprint of meat and dairy is considerably higher than that from plant-based products. If all people within the EU would halve their meat and dairy consumption, this would reduce greenhouse gas emissions from agriculture by 25 to 40%, and nitrogen emissions by 40%. The EU could become a major exporter of food products, instead of a major importer of for example soy beans.”

The work has been conducted by the ‘Task Force on Reactive Nitrogen’ of the United Nations Economic Commission for Europe (UNECE). In 2011 the Task Force produced the first ‘European Nitrogen Assessment’ (ENA) which showed that better nitrogen management will help reduce air, water and soil pollution, greenhouse gas emissions, simultaneously reducing threats to human health, biodiversity and food security.

Co-author of the report Prof Mark Sutton, an Environmental Physicist at the UK’s Centre for Ecology and Hydrology, said, “Human’s use of nitrogen is a major societal challenge that links environment, food security, and human health. There are many ways in which society could improve the way it uses nitrogen, and this includes actions by farmers and by ourselves. Our new study shows that adopting a demitarian* diet across Europe would reduce nitrogen pollution levels by about 40%, which is similar to what could be achieved by adopting low-emission farming practices.”

 

Switch from cattle fields to ‘carbon farms’ could tackle climate change, save endangered animals cheaply

April 30, 2014

James J. Gilroy, Paul Woodcock, Felicity A. Edwards, Charlotte Wheeler, Brigitte L. G. Baptiste, Claudia A. Medina Uribe, Torbjørn Haugaasen, David P. Edwards. Cheap carbon and biodiversity co-benefits from forest regeneration in a hotspot of endemism. Nature Climate Change, 2014; DOI: 10.1038/nclimate2200

 

Changing cattle fields to forests is a cheap way of tackling climate change and saving species threatened with extinction, a new study has found.

Researchers from leading universities, including the University of Sheffield, carried out a survey of carbon stocks, biodiversity and economic values from one of the world’s most threatened ecosystems, the western Andes of Colombia.

The main use of land in communities is cattle farming, but the study found farmers could make the same or more money by allowing their land to naturally regenerate.

Under carbon markets designed to stop global warming, they could get paid to change the use of their land from growing cows to ‘growing carbon’ — receiving around US$1.99 per tonne of carbon dioxide the trees remove from the atmosphere.

The move would also help boost the populations of many critically endangered species.

There are limited financial resources available to tackle climate change and biodiversity loss, so there is an urgent need to simultaneously address both issues.

“This would cost very little money,” said senior scientist, Dr David Edwards, of the University of Sheffield’s Department of Animal and Plant Sciences.

“Providing people are willing to spend the money, this could be a critical mechanism for stopping climate change and protecting some of the world’s most endangered species.

 

 

Better livestock diets to combat climate change, improve food security

February 24, 2014

P. Havlik, H. Valin, M. Herrero, M. Obersteiner, E. Schmid, M. C. Rufino, A. Mosnier, P. K. Thornton, H. Bottcher, R. T. Conant, S. Frank, S. Fritz, S. Fuss, F. Kraxner, A. Notenbaert. Climate change mitigation through livestock system transitions. Proceedings of the National Academy of Sciences, 2014; DOI: 10.1073/pnas.1308044111

 

Livestock production is responsible for 12% of human-related greenhouse gas emissions, primarily coming from land use change and deforestation caused by expansion of agriculture, as well as methane released by the animals themselves, with a lesser amount coming from manure management and feed production.

“There is a lot of discussion about reduction of meat in the diets as a way to reduce emissions,” says IIASA researcher Petr Havlík, who led the study “But our results show that targeting the production side of agriculture is a much more efficient way to reduce greenhouse gas emissions.”

A new study published in the journal Proceedings of the National Academy of Sciences shows that within the current systems, farmers would find it more profitable in coming years to expand livestock production in mixed systems — where livestock are fed on both grass as well as higher quality feed — rather than in pure grass-based systems. This development, would lead to a 23% reduction of emissions from land use change in the next two decades without any explicit climate mitigation policy.

Cows, sheep, and goats grow more quickly and produce more milk when they eat energy-rich diets that include grain supplements or improved forages. This means that more livestock can be raised on less land, and with fewer emissions per pound of meat or milk produced.

The new study projects that the increasing cost of land and continued yield increases in the crop sector will lead to shifts to richer animal diets in the future. Such diets are efficient not only from the perspective of greenhouse gas reduction, but also from farm profit maximization and food production.

At a moderate price of US$10 per ton of carbon dioxide equivalent, livestock system transitions within a given region, together with international relocation of production to regions with the most efficient livestock systems could also reduce the total emissions from agriculture and land use change by 25%. Most of the savings would come from avoided land use change.

Havlík says, “From the livestock sector perspective, limiting land use change seems the cheapest option both in terms of the economic cost and in terms of impact on food availability.”

 

Trade-offs between food security and climate change mitigation explored

July 16, 2013

H Valin, P Havlík, A Mosnier, M Herrero, E Schmid, M Obersteiner. Agricultural productivity and greenhouse gas emissions: trade-offs or synergies between mitigation and food security?
Environmental Research Letters, 2013; 8 (3): 035019 DOI: 10.1088/1748-9326/8/3/035019

 

Improving crop yields using sustainable methods could cut greenhouse gas emissions by as much as 12% per calorie produced according to a new study published in the journal Environmental Research Letters. At the same time, these changes could provide more food to people in need.

Agriculture and land use change contributed about 1/3 of total human greenhouse gas emissions in the past decade, through crop cultivation, animal production, and deforestation. By producing more food on less land, it may be possible to reduce these emissions, but this so-called intensification often involves increasing fertilizer use, which can lead to large emissions of nitrogen-containing gases that also contribute to global warming.

“The most efficient way to ensure sustainable intensification on the crop side is to rely on practices and technologies that are not more fertilizer-demanding, such as new varieties, improved rotations, integrated crop-livestock practices, and precision farming,” says IIASA researcher Hugo Valin, who led the study.

The study’s findings particularly apply to developing countries. In many cases farming in these countries is not as efficient as it could be, and so investing in better farming practices could lead to big benefits both in terms of food security and greenhouse gas emissions.

The study found that increasing livestock yields was more effective at reducing greenhouse gas emissions than increasing yields from crops that people eat. Overall, closing yield gaps by 50% for crops and 25% for livestock would lead to a 12% savings in greenhouse gas emission per calorie produced.

However, says Valin, “Increasing livestock yield is not as beneficial to food security as can be increase crop yield, just because meat and dairy are a small share of diets, especially in developing countries….

 

Eat less meat and farm efficiently to tackle climate change, scientists say

June 19, 2012

Thomas Powell, Tim Lenton. Future carbon dioxide removal via biomass energy constrained by agricultural efficiency and dietary trends. Energy & Environmental Science, 2012; DOI: 10.1039/C2EE21592F

We need to eat less meat and recycle our waste to rebalance the global carbon cycle and reduce our risk of dangerous levels of climate change, according to scientists.

New research from the University of Exeter shows that if today’s meat-eating habits continue, the predicted rise in the global population could spell ecological disaster. But changes in our lifestyle and our farming could make space for growing crops for bioenergy and carbon storage.

Though less efficient as an energy source than fossil fuels, plants capture and store carbon that would otherwise stay in the atmosphere and contribute to global warming. Burning our waste from organic materials, such as food and manure, and any bioenergy crops we can grow, while capturing the carbon contained within them, could be a powerful way to reduce atmospheric carbon dioxide.

Published June  20, 2012 in the journal Energy and Environmental Science, the research suggests that in order to feed a population of 9.3 billion by 2050 we need to dramatically increase the efficiency of our farming by eating less beef, recycling waste and wasting less food. These changes could reduce the amount of land needed for farming, despite the increase in population, leaving sufficient land for some bio-energy. To make a really significant difference, however, we will need to bring down the average global meat consumption from 16.6 per cent to 15 per cent of average daily calorie intake — about half that of the average western diet. The researchers argue that if we change the way we use our land, recycle waste, and dedicate enough space to growing bioenergy crops we could bring down atmospheric carbon dioxide to safe levels. Not doing this means we would lose our natural ecosystems and face increasingly dangerous levels of atmospheric carbon dioxide….

 

Grazing of cattle pastures can improve soil quality

March 3, 2011

USDA/Agricultural Research Service

 

Alan J. Franzluebbers. John A. Stuedemann. Surface Soil Changes during Twelve Years of Pasture Management in the Southern Piedmont USA.  Soil Science Society of America Journal: doi:10.2136/sssaj2010.0034

 

A team of U.S. Department of Agriculture (USDA) scientists has given growers in the Piedmont guidance on how to restore degraded soils and make the land productive. Researchers with the USDA’s Agricultural Research Service (ARS) found that if cattle are managed so that they graze moderately, soil quality can be restored and emissions of carbon dioxide (a greenhouse gas) can be reduced.

The research was recently published in the Soil Science Society of America Journal……

From an environmental standpoint, grasslands have traditionally been viewed as best managed by leaving the land unused. But the team found that while fertilizer type made little difference, different grazing scenarios produced different effects, and the grazed land produced more grass than the ungrazed land and had the greatest amount of carbon and nitrogen sequestered in soil. Sequestering carbon and nitrogen in soil has become a major goal for agriculture, because that sequestration reduces greenhouse gas emissions.

 

Eating Right Can Save the World

 

Fueling up should be healthy for you—and the planet. But how do you figure out the most sustainable diet?    Photo: Hannah McCaughey (2), Sang An, Hannah McCaughey

Eating Right Can Save the World

The endless cascade of nutritional information—about localism, vegetarianism, veganism, organic food, the environmental impact of eating meat, poultry, or fish, and more—makes the simple goal of a healthy, sustainable diet seem hopelessly complex. We talked to scientists, chefs, and farmers to get the ultimate rundown on how you should fuel up.

By:
Tim Zimmermann Jan 7, 2016 Outside Magazine

…. Tell me what you eat and I will tell you how you impact the planet. Most of us are aware that our food choices have environmental consequences. …. Are organic fruits and vegetables really worth the higher prices, and are they better for the environment? If I’m a meat eater, should I opt for free-range, grass-fed beef? Is it OK to buy a pineapple flown in from Costa Rica, or should I eat only locally grown apples? 

The science of food’s ecological footprint can be overwhelming, yet it’s important to understand it. For starters, in wealthy societies food consumption is estimated to account for 20 to 30 percent of the total footprint of a household. Feeding ourselves dominates our landscapes, using about half the ice-free land on earth. It sends us into the oceans, where we have fished nearly 90 percent of species to the brink or beyond. It affects all the planet’s natural systems, producing more than 30 percent of global greenhouse gases. Farming uses about 70 percent of our water and pollutes rivers with fertilizer and waste that in turn create vast coastal dead zones. The food on your plate touches everything.
“If you look at the heavy-hitter list of global-scale changes that are human induced, how we feed ourselves is invariably near the top,” says Peter Tyedmers, a professor at Dalhousie University’s School for Resource and Environmental Studies (SRES) in Halifax, Nova Scotia, who has been studying the world’s food systems for 15 years. “But the great thing about food is that we have choices, and we have the opportunity to effect change three times a day.” ….….Here’s a sense of what the planet might reap in return. A 2015 study conducted by the journal Frontiers in Nutrition concluded that a diet that is vegetarian five days a week and includes meat just two days a week would reduce greenhouse-gas emissions and water and land use by about 45 percent…. Does eating grass-fed, free-range meat let you off the hook? Not really, because meat takes a toll no matter how it’s raised. Studies actually show that a factory-farm animal emits fewer greenhouse gases than a free-range one, because it lives a shorter life. But Greg Fogel, a senior policy specialist at the National Sustainable Agriculture Coalition, points out that factory farms in the U.S. produce 13 times as much sewage as the entire human population and that environmental impact is about more than greenhouse gases. “The meat you do eat should be grass-fed meat from managed grazing operations,” he says. “Rotational grazing systems recycle manure as fertilizer, improve wildlife habitat, and enhance plant root systems, increasing soil quality, water infiltration and flood control, and carbon sequestration.”… As it happens, the seafood with the smallest carbon footprint is frequently the seafood that’s best to eat if you’re looking to reduce pressure on wild fisheries…. Clearly, eating less meat has big environmental payoffs. But what about not eating it at all? I’d never crunched the numbers to find out how much more climate-friendly a plant-based diet really is. The results are telling. For example, in the Frontiers in Nutrition study, researchers compared the greenhouse-gas, water, and land footprints of a balanced 2,000-calorie vegetarian diet, including eggs and dairy, with those of a balanced 2,000-calorie omnivore diet that included one serving of meat per day: a 5.3-ounce steak. The vegetarian diet reduced greenhouse-gas emissions by 63 percent and required 61 percent less land and 67 percent less water.
Another study, in the European Journal of Clinical Nutrition, also compared an omnivorous diet to a vegetarian one. It considered a broad array of environmental impacts beyond climate change and land use—including cancer rates, effect on the ozone layer, and waterway pollution—to produce a more complete model. It concluded that the vegetarian diet had just 64 percent of the environmental impact of the omnivore diet…

….Plant-based protein choices also carry different environmental costs. Wheat accounts for one-fifth the greenhouse-gas emissions of water-thirsty rice per gram of protein. Legumes are even better, at one-quarter the emissions of wheat. Being thoughtful about protein alternatives yields even more environmental payoff. Lentils and chickpeas, for example, are better than soybeans at fixing nitrogen in the soil and help you avoid soy’s GMO issues. And quinoa is packed with protein and grows well in a variety of soils…..

…Organic farming, Nichols tells me, is really about the health of the soil and the ecosystems producing our food.
Nichols wants to show me the difference between soil from conventional agriculture, which uses chemical fertilizers and pesticides, and soil from what Rodale calls regenerative organic agriculture, which uses natural pest management, extensive cover crops, and natural fertilizer like manure. …

…according to one analysis I found, buying local can reduce the impact of vegetable production by 10 to 30 percent. Other researchers have calculated that produce moving through the national transportation network that supplies large grocery stores travels an average of about 1,518 miles and emits five to seventeen times the greenhouse gases of regional and local food distribution. In contrast, locally sourced foods travel an average of just 45 miles. 

So it makes sense to buy local whenever possible, another reason to spend time at the nearest farmers’ market. If you’re really dedicated to sustainable eating, that means eating seasonally as well. No more grapes and strawberries from Chile in February….

You’re Throwing Away Too Much Food

No matter where you come down on meat, organic, and shopping locally, there are two powerful sustainability strategies you can put to work right now. The first is to eat less. If the average omnivore, who eats around 3,500 calories a day, instead ate a diet closer to his basic nutritional requirement of 2,500 calories, he would likely reduce his environmental footprint by about 30 percent. An active person who works out daily needs closer to 2,800 calories, yielding a roughly 20 percent cut.

The second strategy: waste less. In the U.S., 40 percent of food—worth an estimated $165 billion—is thrown out every year. It’s an environmental and social-policy tragedy.
According to the USDA, which in September announced an initiative to try and cut American food waste in half, the average family of four trashes two million calories a year, worth nearly $1,500. As a result, 25 percent of America’s water is used to produce food that is never eaten, and an estimated 28 percent of the planet’s agricultural land is used to grow food that ends up in the garbage. Food is the single largest solid-waste component of America’s landfills—an estimated 80 billion pounds—and emissions from it are equivalent to the greenhouse-gas output of 33 million cars. ..

…Stop worrying so much about not getting enough protein…Buy organic food whenever you can. Source your food as locally as possible, and eat seasonally to avoid racking up major food miles. Eat less and waste less. Be open-minded and creative about new cuisines. Relax. Have fun. Sustainable eating isn’t synonymous with masochism. ..

Ocean acidification affects ability of bacteria to clean our oceans

What is acidification?
Oceana.org

 

 

Acidification affects the ability of bacteria to clean our oceans

Posted: 12 Jan 2016 06:18 AM PST

Marine bacteria are heavily influenced by the ongoing ocean acidification caused by human emissions of carbon dioxide.
… The results are presented in an article in the scientific journal Nature Climate Change. “It is well known that the acidification of our oceans causes the degradation of coral reefs and disturbs the production of the calcareous shells of important phytoplankton,” says Jarone Pinhassi, professor in marine microbiology at Linnaeus University in Kalmar, Sweden. “However, it is new that also bacteria are affected negatively by ocean acidification.” Researchers at Linnaeus University can now show that bacteria in the ocean that are exposed to acidification are forced to significantly alter their metabolism; from focusing on degradation to investing energy on dealing with the acid in the water. Bacteria in our oceans play a crucial role in the global cycle of elements necessary to life.

They act primarily as degraders of organic material produced by microscopic algae in the ocean, or material released through wastewater.
When algae or other organisms die and are degraded by bacteria, these miniscule organisms function as the wastewater treatment plants of the ocean. At the same time, bacteria help release nutrients like nitrogen and phosphorus, which are essential to the food chain. It is estimated that the world’s oceans will become three times more acid towards the end of this century if human emissions of carbon dioxide from combustion of fossil fuels continue at current rates……says Jarone Pinhassi. “Now our genetic analyses show that ocean acidification directly affect how bacteria regulate their metabolism.“… In every litre of seawater there are around 1 billion bacterial cells. In a manner similar to how gut microbiota is important to the well-being of humans, bacteria in our oceans play a critical role in determining the health of marine ecosystems. For example, bacteria synthesise vitamins on which algae and other organisms in the oceans depend. “In order to understand the consequences of future climate change on the productivity of the ocean, it is essential to carry out research on how bacteria respond to human emissions of carbon dioxide,” says Jarone Pinhassi. “Perhaps we can even learn how to take advantage of the genetic adaptations of marine bacteria, in order to make better use of the resources of our planet.”

 

Carina Bunse, Daniel Lundin, Christofer M. G. Karlsson, Maria Vila-Costa, Joakim Palovaara, Neelam Akram, Lovisa Svensson, Karin Holmfeldt, José M. González, Eva Calvo, Carles Pelejero, Cèlia Marrasé, Mark Dopson, Josep M. Gasol, Jarone Pinhassi. Response of marine bacterioplankton pH homeostasis gene expression to elevated CO2. Nature Climate Change, 2016; DOI: 10.1038/nclimate2914

Early data shows 2015 blew away previous records to become Earth’s hottest year

Global temperature anomaly for 2015 compared to the 1951-1980 average. Image: Berkeley Earth

Early data shows 2015 blew away previous records to become Earth’s hottest year

By Andrew Freedman January 13 2016 Mashable

During the next week, the official climate agencies around the world that are responsible for tracking the planet’s average temperatures will almost certainly come to the same conclusion: 2015 was the warmest year on record. This would mean that 2015 would beat the previous warmest year, which occurred in 2014 — remember that? The combination of a record strong El Niño event plus the highest amount of greenhouse gases in the atmosphere at any time in human history have given the climate system the equivalent of a Power Bar plus a shot of espresso. On Wednesday, one unofficial temperature tracking group, known as Berkeley Earth, revealed its determination that 2015 was by far the planet’s warmest year, both on land and sea.
There’s one especially important about fact about this group’s determination: It was set up in early 2010 as an independent fact check of other surface temperature data sets, and led by a physicist — Richard Muller — who had previously been quite skeptical of mainstream climate science findings. Instead of proving surface data from government agencies like NASA and the National Oceanic and Atmospheric Administration (NOAA) wrong, the Berkeley group has consistently reaffirmed their data…The Berkeley Earth group said in a release on Wednesday that “2015 was unambiguously the hottest year on record.”
More importantly, the group found that for the first time in recorded history, the Earth’s temperature is clearly more than 1 degree Celsius (1.8 degrees Fahrenheit) above the 1850-1900 average, and halfway to world leaders’ climate target of limiting global warming to under 2 degrees Celsius (3.6 degrees Fahrenheit) above average.

This is your brain on nature: reducing stress

 

 

 

Within sight of downtown Seoul, capital of South Korea and a hub of stressful modern life, salesman Sungvin Hong rests after a hike in Bukhansan National Park. The park attracts some five million visitors a year.

This Is Your Brain on Nature

When we get closer to nature—be it untouched wilderness or a backyard tree—we do our overstressed brains a favor.

Story by Florence Williams Photographs by Lucas Foglia Published December 8, 2015 National Geographic Magazine  |  January 2016

When you head out to the desert, David Strayer is the kind of man you want behind the wheel. He never texts or talks on the phone while driving. He doesn’t even approve of eating in the car. A cognitive psychologist at the University of Utah who specializes in attention, Strayer knows our brains are prone to mistakes, especially when we’re multitasking and dodging distractions. Among other things, his research has shown that using a cell phone impairs most drivers as much as drinking alcohol does. Strayer is in a unique position to understand what modern life does to us. An avid backpacker, he thinks he knows the antidote: Nature.…. In England researchers from the University of Exeter Medical School recently analyzed mental health data from 10,000 city dwellers and used high-resolution mapping to track where the subjects had lived over 18 years. They found that people living near more green space reported less mental distress, even after adjusting for income, education, and employment (all of which are also correlated with health). In 2009 a team of Dutch researchers found a lower incidence of 15 diseases—including depression, anxiety, heart disease, diabetes, asthma, and migraines—in people who lived within about a half mile of green space. And in 2015 an international team overlaid health questionnaire responses from more than 31,000 Toronto residents onto a map of the city, block by block. Those living on blocks with more trees showed a boost in heart and metabolic health equivalent to what one would experience from a $20,000 gain in income. Lower mortality and fewer stress hormones circulating in the blood have also been connected to living close to green space.

It’s difficult to tell from these kinds of studies why people feel better. Is it the fresh air? Do certain colors or fractal shapes trigger neurochemicals in our visual cortex? Or is it just that people in greener neighborhoods use the parks to exercise more? … What he and other researchers suspect is that nature works primarily by lowering stress. Compared with people who have lousy window views, those who can see trees and grass have been shown to recover faster in hospitals, perform better in school, and even display less violent behavior in neighborhoods where it’s common. Such results jibe with experimental studies of the central nervous system. Measurements of stress hormones, respiration, heart rate, and sweating suggest that short doses of nature—or even pictures of the natural world—can calm people down and sharpen their performance… All this evidence for the benefits of nature is pouring in at a time when disconnection from it is pervasive, says Lisa Nisbet, a psychology professor at Canada’s Trent University. We love our state and national parks, but per capita visits have been declining since the dawn of email. So have visits to the backyard. One recent Nature Conservancy poll found that only about 10 percent of American teens spend time outside every day. According to research by the Harvard School of Public Health, American adults spend less time outdoors than they do inside vehicles—less than 5 percent of their day…. Nooshin Razani at UCSF Benioff Children’s Hospital in Oakland, California, is one of several doctors who have noticed the emerging data on nature and health. As part of a pilot project, she’s training pediatricians in the outpatient clinic to write prescriptions for young patients and their families to visit nearby parks. It’s not as simple as taking a pill. To guide the physicians and patients into a new mind-set, she says, “we have transformed the clinical space so nature is everywhere. There are maps on the wall, so it’s easy to talk about where to go, and pictures of local wilderness, which are healing to look at for both the doctor and patient.” The hospital is partnering with the East Bay Regional Parks District to provide transportation to parks and programs there for entire families…. Strayer is most interested in how nature affects higher order problem solving. His research builds on the attention restoration theory proposed by environmental psychologists Stephen and Rachel Kaplan at the University of Michigan. They argue that it’s the visual elements in natural environments—sunsets, streams, butterflies—that reduce stress and mental fatigue. Fascinating but not too demanding, such stimuli promote a gentle, soft focus that allows our brains to wander, rest, and recover from what Olmsted called the “nervous irritation” of city life. “Soft fascination … permits a more reflective mode,” wrote the Kaplans—and the benefit seems to carry over when we head back indoors. A few years ago, for example, in an experiment similar to Bratman’s, Stephen Kaplan and his colleagues found that a 50-minute walk in an arboretum improved executive attention skills, such as short-term memory, while walking along a city street did not. “Imagine a therapy that had no known side effects, was readily available, and could improve your cognitive functioning at zero cost,” the researchers wrote in their paper. It exists, they continued, and it’s called “interacting with nature.“…

SF Bay Area Parcel Tax for Tidal Marsh Restoration on Ballot for June 2016

The Facebook campus sits next to the Menlo Park Baylands amid the rich colors of the drying mud flats in Ravenswood Slough in this aerial view taken Wednesday afternoon, Sept. 2, 2015, in Menlo Park, Calif. (Karl Mondon)

First-of-its-kind $12 parcel tax proposed for all nine Bay Area counties

By Paul Rogers San Jose Mercury News Posted:   01/13/2016 06:09:53 AM PST

In a milestone for San Francisco Bay restoration that also raises questions about who should pay to protect property from rising seas caused by climate change, a low-profile government agency is expected to place a $12 annual parcel tax on the June ballot in all nine Bay Area counties.

The measure, whose campaign is being bankrolled by Silicon Valley business leaders and Bay Area environmental groups, is believed to be the first local tax ever placed before voters in all nine Bay Area counties. If approved by two-thirds of voters, the tax would raise $500 million over the next 20 years to build levees and restore thousands of acres of wetlands and tidal marshes as a buffer to storm surges and floods in every Bay Area county. “The bay is a beautiful asset we all want to protect and restore,” said Carl Guardino, CEO of the Silicon Valley Leadership Group, which represents 390 large technology companies and other employers. “… The leadership group, along with Save the Bay and the Bay Area Council, a business group, already has raised $700,000 toward a campaign and plans to raise up to $5 million. Influential leaders such as Robert Fisher of the Gap and John Doerr, a Silicon Valley venture capitalist, already have donated to the campaign….Environmentalists say the measure is critical in helping fulfill long-term restoration plans around the bay. A study in October by more than 100 scientists, coordinated by the Coastal Conservancy and other organizations, found that 54,000 acres of wetlands — an area twice the size of the city of San Francisco — need to be restored around the bay in the next 15 years to provide protection from surging storms. The alternative is concrete sea walls, which can cost more and would turn the bay into a giant bathtub over time, with far fewer birds, fish and other wildlife, the report concluded. Driven by melting ice and expanding warming water, the bay and the Pacific Ocean off California will rise up to 1 foot in the next 20 years, 2 feet by 2050 and up to 5 feet by 2100, according to a 2012 study by the National Academy of Sciences.

“This is the most important thing we can do for the bay,” said David Lewis, executive director of Oakland-based Save the Bay. “There’s an urgency to restore tidal marshes, for ecological benefits and flood control benefits. The sooner we start the sooner they can provide benefits. But money has been the missing ingredient for a long time.”

California’s state fish can benefit from restoring and protecting streamside vegetation in high elevation meadows

 

Credit: US Forest Service

California’s state fish can benefit from restoring and protecting streamside vegetation in high elevation meadows Phys. Org. January 14, 2016

Rising temperatures can create stressful and possibly lethal stream habitat for native trout. To help understand the interactive effects of climate warming and livestock grazing on water temperature, researchers from the Pacific Southwest Research Station (PSW) and University of California, Berkeley, conducted a six-year study documenting high elevation water temperatures in areas of the Golden Trout Wilderness. The wilderness area is located within the Sequoia and Inyo national forests in California and was designated Wilderness primarily to protect the native California golden trout, the state’s official fish.

To understand the impact of land use on water temperature, researchers measured streamside vegetation and monitored water temperature in three meadow streams where livestock had three different types of stream access between 2008 and 2013. Key findings include: Water temperatures approached the upper limit of tolerance for the golden trout in some areas of suitable habitat. Water temperatures were cooler in ungrazed meadow areas with willows. Riverbank vegetation was both larger and denser where livestock were not present.

In the study, researchers found that land use can interact with climate change to intensify warming in high elevation meadow streams, and protecting and restoring streamside vegetation can help keep streams cool for the California golden trout. “Our study clearly shows the role of streamside vegetation in maintaining low stream temperatures,” said Kathleen Matthews, a PSW research scientist and co-author of the study. “Enhancing and protecting streamside vegetation may ensure that streams have the resiliency to withstand future climate warming that can lead to stressful and possibly lethal stream temperatures for golden trout.”
The paper, “Mediating Water Temperature Increases Due to Livestock and Global Change in High Elevation Meadow Streams of the Golden Trout Wilderness,” was released in the journal PLOS One.

Current pace of environmental change is unprecedented in Earth’s history

 

Current pace of environmental change is unprecedented in Earth’s history

4 January 2016

University of Bristol Cabot Institute researchers and their colleagues today published research that further documents the unprecedented rate of environmental change occurring today, compared to that which occurred during natural events in Earth’s history. The research, published online on 4 January in Nature Geoscience reconstructs the changes in atmospheric carbon dioxide (pCO₂) during a global environmental change event that occurred about 120 Million years ago. New geochemical data provide evidence that pCO₂ increased in response to volcanic outgassing and remained high for around 1.5-2 million years, until enhanced organic matter burial in an oxygen-poor ocean caused a return to original levels.  Lead author Dr David Naafs explained: ‘Past records of climate change must be well characterised if we want to understand how it affected or will affect ecosystems. It has been suggested that the event we studied is a suitable analogue to what is happening today due to human activity and that a rapid increase in pCO₂ caused ocean acidification and a biological crisis amongst a group of calcifying marine algae. Our work confirms that there was a large increase in pCO₂. The change, however, appears to have been far slower than that of today, taking place over hundreds of thousands of years, rather than the centuries over which human activity is increasing atmospheric carbon dioxide levels. So despite earlier claims, our research indicates that it is extremely unlikely that widespread surface ocean acidification occurred during this event.’ The observation that yet another putative ‘rapid’ geological event is occurring perhaps a thousand times slower than today and not associated with widespread surface ocean acidification has been the focus of much recent research at the University of Bristol. Co-author Professor Daniela Schmidt, who was also a Lead Author on the IPCC WGII report on Ocean systems, emphasised that today’s finding builds on one of the IPCC’s key conclusions: that the rate of environmental change occurring today is largely unprecedented in Earth history.  She said, ‘This is another example that the current rate of environmental change has few if any precedents in Earth history, and this has big implications for thinking about both past and future change.‘…

Private lands habitat program benefit California’s native birds

 

Private lands habitat programs benefit California’s native birds

BY Ryan T. DiGaudio*, Kimberly E. Kreitinger**, Catherine M. Hickey*, Nathaniel E. Seavy*, Thomas Gardali* California Agriculture, October-December 2015
Volume 69, Number 4.

*Point Blue Conservation Science

**Wisconsin Society for Ornithology, Madison, WI

To address the loss of wetlands and riparian forests in California, private lands habitat programs are available through U.S. federal and state government agencies to help growers, ranchers and other private landowners create and enhance wildlife habitat. The programs provide financial and technical assistance for implementing conservation practices. To evaluate the benefits of these programs for wildlife, we examined bird use of private wetlands, postharvest flooded croplands and riparian forests enrolled in habitat programs in the Central Valley and North Coast regions of California. We found that private Central Valley wetlands supported 181 bird species during the breeding season. During fall migration, postharvest flooded croplands supported wetland-dependent species and a higher density of shorebirds than did semipermanent wetlands. At the riparian sites, bird species richness increased after restoration. These results demonstrated that the programs provided habitat for the species they were designed to protect; a variety of resident and migratory bird species used the habitats, and many special status species were recorded at the sites.

Geoengineering 101

 

Geoengineering 101: Your Geoengineering Cheat Sheet

Who’s who in climate engineering? What are the big ethical debates? And what the heck is the albedo?

By Jacob Brogan slate.com Jan 6 2016

Geoengineering describes the active transformation of our planet’s climate through human intervention. Here are some of the key players, major debates, and pop cultural landmarks shaping the ways that we understand this emerging field.

KEY PLAYERS:

Paul Crutzen: Crutzen, a Nobel Prize–winning atmospheric chemist, helped legitimize scientific conversations about geoengineering with his 2006 paper about seeding the atmosphere with sulfur to reflect sunlight back into space.

Peter Eisenberger: Working to extract carbon dioxide from the air through his company Global Thermostat, Eisenberger is at the forefront of the still-developing business side of geoengineering.

Russ George: In 2012, the climate entrepreneur George attempted an unauthorized experiment in iron fertilization, dumping large quantities of metal into the ocean to stimulate the growth of carbon-consuming phytoplankton.

Newt Gingrich: The former speaker of the House, Gingrich is one of geoengineering’s most politically connected advocates, insisting that it’s an important weapon in the fight against climate change.

David Keith: Having literally written the book on solar radiation management, Harvard Kennedy School professor Keith also works to advance the science of CO2 reduction with his company Carbon Engineering.

Marcia McNutt: An oceanographer and editor-in-chief of Science, McNutt chaired the National Academy of Sciences’ comprehensive inquiry into geoengineering, which published its findings in February 2015.

Nathan Myhrvold: The former chief technology officer of Microsoft, Myhrvold has proposed a project he calls the Stratoshield, in which giant hoses would be lifted into the sky by balloons to spray aerosols into the upper atmosphere.

Raymond Pierrehumbert: A University of Oxford–based climatologist, Pierrehumbert has vocally argued against geoengineering by solar radiation management, famously calling such efforts “barking mad.”

Alan Robock: Rutgers University professor Robock’s widely discussed “Twenty Reasons Why Geoengineering May Be a Bad Idea” provided a sweeping response to the proposals of Crutzen and other geoengineering advocates.

Lynn Russell: An atmospheric scientist based at Scripps, Russell has led research into the potential impacts of geoengineering on ecosystems.

MAJOR DEBATES.

Further environmental degradation: Though some geoengineering technologies may help cool the planet, it’s possible that they may release additional greenhouse gasses, harm the ozone layer, or otherwise advance the damage they aim to prevent. Is geoengineering an environmental dead end?

Induced complacency: Even geoengineering’s advocates acknowledge that it’s not a true solution to climate change. But if it’s successfully implemented, will it prevent us from doing more to save the planet? Will it simply give us permission to keep burning fossil fuels?

International cooperation: In the absence of treaties regulating geoengineering, there’s a risk that companies or countries will pursue projects without taking proper precautions—and the climate doesn’t respect national borders. Some commentators even worry that “rogue billionaires” might take matters into their own hands. Can we regulate geoengineering without restricting innovation?

Long-term commitment: Scientists such as Pierrehumbert argue that we’ll have to stick with geoengineering some technologies for thousands of years once we embrace them, lest we cause even worse catastrophes. Will civilization stay stable for long enough to make a difference?

Price tag: At present, the most effective geoengineering technologies are prohibitively expensive, often less cost-effective than converting to environmentally safe energies. Can scientists bring down the expense? Or should we pursue these avenues regardless?

Unequal effects: Most geoengineering proposals would have different (and often unpredictable) effects on different regions of the planet. Even as some benefit, others would potentially suffer colder winters, decreased rainfall, or other problems. How can we assure that it helps all?

Unintended consequences: We lack the technological sophistication to accurately model most geoengineering proposals on a global scale, making it difficult to anticipate their effects. Should we continue researching these consequences or try to aggressively push the technology ahead?

Weaponization: Many geoengineering proposals originate in Cold War technologies. As the science advances, will we be able to prevent their renewed use as weapons? How can we prevent climatological conflicts?

POP CULTURE: see here

READ UP:

“20 Reasons Why Geoengineering May Be a Bad Idea,” by Alan Robock: Despite its listicle format, this thoroughly annotated article offers one of the most comprehensive, rigorous challenges to geoengineering advocates.

“Albedo Enhancement by Stratospheric Sulfur Injections,” by Paul Crutzen: With this seminal paper, Crutzen helped to legitimize scientific conversations about geoengineering.

A Case for Climate Engineering, by David Keith: In this readable volume, climate scientist Keith makes a passionate case for albedo modification technologies, exploring their promise and the effort required to put them into practice.

Climate Intervention Reports, by the National Academy of Sciences: The product of years of research, this report comes close to offering the scientific consensus on both carbon dioxide removal and albedo modification.

“The Ethics of Geoengineering,” by David Appell: The first of a two-part series, this essay offers a thorough, balanced examination of geoengineering’s risks, as well as its possible rewards.

The Planet Remade, by Oliver Morton: Even as he discusses the science behind geoengineering technologies, Morton goes deep into the social and political anxieties that hover around them.

LINGO:

Albedo: The portion of sunlight that the Earth reflects back into space. The albedo is shaped by factors like cloud cover and snowfall.

Biological pump: Under ordinary circumstances, oceanic plankton naturally pull CO2 out of the atmosphere. By increasing plankton quantities, some geoengineers hope to reduce atmospheric CO2 levels.

Carbon dioxide reduction: A key geoengineering strategy, carbon dioxide reduction would involve removing pollutants directly from the air.

Ocean fertilization: The artificial stimulation of the ocean’s biological pump. Ocean fertilization might help pull CO2 out of the atmosphere, but it could also damage fisheries.

Solar radiation management: The second major geoengineering strategy, solar radiation management aims to cool the Earth by increasing its reflective properties (see albedo).