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  1. 25% of food producers contribute ~53% of that product’s environmental impacts; lower impact animal products have higher environmental impact than vegetable equivalents per new SCIENCE study

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    • Impacts of the lowest-impact animal products typically exceed those of vegetable substitutes, providing new evidence for the importance of dietary change.
    • Cumulatively, our findings support an approach where producers monitor their own impacts, flexibly meet environmental targets by choosing from multiple practices, and communicate their impacts to consumers.
    • A small number of producers create much of the impact. Just 15% of beef production creates ~1.3 billion tonnes of CO2 equivalents and uses ~950 million hectares of land.
    • Across all products, 25% of producers contribute on average 53% of each product’s environmental impacts [across 5 indicators: GHG emissions, land use, terrestrial acidification,eutrophication, and scarcity-weighted freshwater withdrawals]. This variation and skew highlights potential to reduce impacts and enhance productivity in the food system.
    • Researchers found that the variability in the food system fails to translate into animal products with lower impacts than vegetable equivalents. For example, a low-impact (10th percentile) litre of cow’s milk uses almost two times as much land and creates almost double the emissions as an average litre of soymilk.
    • Reducing consumption of animal products by 50% by avoiding the highest-impact producers achieves 73% of the previous scenarios GHG emission reduction for example.
    • Irrigation returns less water to rivers and groundwater than industrial and municipal uses and predominates in water-scarce areas and times of the year, driving 90 to 95% of global scarcity weighted water use
    • Further, lowering consumption of discretionary products (oils, alcohol, sugar, and stimulants) by 20% by avoiding high-impact producers reduces the greenhouse gas emissions of these products by 43%. This creates a multiplier effect, where small behavioural changes have large consequences for the environment
    • Communicating average product impacts to consumers enables dietary change and should be pursued

    May 31, 2018 University of Oxford Read full ScienceDaily article here

    Read Guardian UK article on this study here: Avoiding meat and dairy is ‘single biggest way’ to reduce your impact on Earth

    New research highlights the environmental impacts of thousands of food producers and their products, demonstrating the need for new technology to monitor agriculture and environmental labels on food products.

    They found large differences in environmental impact between producers of the same product. High-impact beef producers create 105kg of CO2 equivalents and use 370m2 of land per 100 grams of protein, a huge 12 and 50 times greater than low-impact beef producers. Low-impact beef producers then use 36 times more land and create 6 times more emissions than peas.

    Aquaculture, assumed to create relatively little emissions, can emit more methane, and create more greenhouse gases than cows per kilogram of liveweight. One pint of beer, for example, can create 3 times more emissions and use 4 times more land than another. This variation in impacts is observed across all five indicators they assess, including water use, eutrophication, and acidification. [5 indicators: GHG emissions, land use, terrestrial acidification,
    eutrophication, and scarcity-weighted freshwater withdrawals]

    “Two things that look the same in the shops can have very different impacts on the planet. We currently don’t know this when we make choices about what to eat. Further, this variability isn’t fully recognised in strategies and policy aimed at reducing the impacts of farmers.” says Joseph Poore from the Department of Zoology and the School of Geography and Environment.

    …Specifically the researchers found that the variability in the food system fails to translate into animal products with lower impacts than vegetable equivalents. For example, a low-impact (10th percentile) litre of cow’s milk uses almost two times as much land and creates almost double the emissions as an average litre of soymilk.

    ….Reducing consumption of animal products by 50% by avoiding the highest-impact producers achieves 73% of the previous scenarios GHG emission reduction for example. Further, lowering consumption of discretionary products (oils, alcohol, sugar, and stimulants) by 20% by avoiding high-impact producers reduces the greenhouse gas emissions of these products by 43%. This creates a multiplier effect, where small behavioural changes have large consequences for the environment….

    J. Poore, T. Nemecek. Reducing food’s environmental impacts through producers and consumers. Science, 2018 DOI: 10.1126/science.aaq0216

    Abstract

    Food’s environmental impacts are created by millions of diverse producers. To identify solutions that are effective under this heterogeneity, we consolidated data covering five environmental indicators; 38,700 farms; and 1600 processors, packaging types, and retailers. Impact can vary 50-fold among producers of the same product, creating substantial mitigation opportunities. However, mitigation is complicated by trade-offs, multiple ways for producers to achieve low impacts, and interactions throughout the supply chain. Producers have limits on how far they can reduce impacts. Most strikingly, impacts of the lowest-impact animal products typically exceed those of vegetable substitutes, providing new evidence for the importance of dietary change. Cumulatively, our findings support an approach where producers monitor their own impacts, flexibly meet environmental targets by choosing from multiple practices, and communicate their impacts to consumers.

    From the paper:

    ….Today’s food supply chain creates ~1 3.7 billion metric tons of carbon dioxide equivalents (CO2eq), 26% of anthropogenic GHG emissions. A further 2.8 billion metric tons of CO2eq (5%) are caused by nonfood agriculture and other drivers of deforestation(17). Food production creates ~32% of global terrestrial acidification and ~78% of eutrophication. These emissions can fundamentally alter the species composition of natural ecosystems, reducing biodiversity and ecological resilience (19). The farm stage dominates, representing 61% of food’s GHG emissions (81%including deforestation), 79% of acidification, and 95% of eutrophication (table S17). Today’s agricultural system is also incredibly resource intensive, covering ~43% of the world’s ice- and desert-free land. Of this land, ~87% is for food and 13% is for biofuels and textile crops or is allocated to nonfood uses such as wool and leather.We estimate that two-thirds of freshwater withdrawals are for irrigation. However, irrigation returns less water to rivers and groundwater than industrial and municipal uses and predominates in water-scarce areas and times of the year, driving 90 to 95% of global scarcity weighted water use (17).

    ….Communicating average product impacts to consumers enables dietary change and should be pursued. Though dietary change is realistic for any individual, widespread behavioral change will be hard to achieve in the narrow time frame remaining to limit global warming and prevent further, irreversible biodiversity loss. Communicating producer impacts allows access to the second scenario, which multiplies the effects of smaller consumer changes.

  2. White House quietly cancels NASA research verifying greenhouse gas cuts

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    • “If you cannot measure emissions reductions, you cannot be confident that countries are adhering to the agreement,” she says. Canceling the CMS “is a grave mistake

    By Paul Voosen May. 9, 2018  Read full Science Magazine article here

    You can’t manage what you don’t measure. The adage is especially relevant for climate-warming greenhouse gases, which are crucial to manage—and challenging to measure. In recent years, though, satellite and aircraft instruments have begun monitoring carbon dioxide and methane remotely, and NASA’s Carbon Monitoring System (CMS), a $10-million-a-year research line, has helped stitch together observations of sources and sinks into high-resolution models of the planet’s flows of carbon. Now, [the White House] has quietly killed the CMS, Science has learned.

    The move jeopardizes plans to verify the national emission cuts agreed to in the Paris climate accords, says Kelly Sims Gallagher, director of Tufts University’s Center for International Environment and Resource Policy in Medford, Massachusetts. “If you cannot measure emissions reductions, you cannot be confident that countries are adhering to the agreement,” she says. Canceling the CMS “is a grave mistake,” she adds….

  3. US power sector carbon emissions intensity drops to lowest on record

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    • U.S. power plant emissions averaged 967 lb. CO2 per megawatt-hour (MWh) in 2017, which was down 3.1 percent from the prior year and down 26.8 percent from the annual value of 1,321 lb CO2 per MWh in 2005.

    April 4, 2018 College of Engineering, Carnegie Mellon University Read full ScienceDaily article here

    Researchers have announced the release of the 2018 Carnegie Mellon Power Sector Carbon Index. The Index tracks the environmental performance of US power producers and compares current emissions to more than two decades of historical data collected nationwide. This release marks the one-year anniversary of the Index, developed as a new metric to track power sector carbon emissions performance trends.

    ….The latest data revealed the following findings: U.S. power plant emissions averaged 967 lb. CO2 per megawatt-hour (MWh) in 2017, which was down 3.1 percent from the prior year and down 26.8 percent from the annual value of 1,321 lb CO2 per MWh in 2005. The result for 2016 was initially reported as 1,001 lb/MWh, but was later revised downward to 998 lb/MWh.

  4. Climate change threatens world’s largest seagrass carbon stores

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    • Seagrass meadows are CO2 sinks, known as ‘Blue Carbon ecosystems’. They take up and store carbon dioxide in their soils and biomass through biosequestration.
    • we need to advance our understanding of how seagrass ecosystems, especially those living close to their thermal tolerance, will respond to global change threats, both direct and through interactive effects with local pressures.

    March 19, 2018 Universitat Autònoma de Barcelona  read full ScienceDaily article here

    In the summer of 2010-2011 Western Australia experienced an unprecedented marine heat wave that elevated water temperatures 2-4°C above average for more than 2 months. The heat wave resulted in defoliation of the dominant Amphibolis antarctica seagrass species across the iconic Shark Bay World Heritage Site…

    ….Over the three years following the event, the loss of seagrass released up to nine million metric tons of carbon dioxide (CO2) into the atmosphere. This amount is roughly the equivalent to the annual CO2 output of 800,000 homes, two average coal-fired power plants, or 1,600,000 cars driven for 12 months. It also potentially raised Australia’s annual estimate of national land-use change CO2 emissions by up to 21%….

    …”This is significant, as seagrass meadows are CO2 sinks, known as ‘Blue Carbon ecosystems’. They take up and store carbon dioxide in their soils and biomass through biosequestration. The carbon that is locked in the soils is potentially there for millennia if seagrass ecosystems remain intact,” explains Professor Pere Masqué, co-author of the study and researcher at ICTA-UAB and the UAB Department of Physics….

    …”We need to advance our understanding of how seagrass ecosystems, especially those living close to their thermal tolerance, will respond to global change threats, both direct and through interactive effects with local pressures….

    A. Arias-Ortiz, O. Serrano, P. Masqué, P. S. Lavery, U. Mueller, G. A. Kendrick, M. Rozaimi, A. Esteban, J. W. Fourqurean, N. Marbà, M. A. Mateo, K. Murray, M. J. Rule & C. M. Duarte. A marine heatwave drives massive losses from the world’s largest seagrass carbon stocks. Nature Climate Change, 2018 DOI: 10.1038/s41558-018-0096-y

  5. 20% of Americans responsible for 46% of US food-related greenhouse gas emissions

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    • 20 percent of Americans account for nearly half of U.S. diet-related greenhouse gas emissions, and high levels of beef consumption are largely responsible
    • The researchers did not look specifically at how the beef was produced, which can influence its carbon footprint. “That information is not available on the dietary side,” Heller said [in a related Inside Climate News article]. “People aren’t saying where their beef is coming from or how it was raised. It was just beef.”
      • [Ellie’s note: this likely reflects CAFO cattle (cattle in concentrated agriculture feeding operations) in this national study as opposed to specific grass fed, grass finished beef which also provides other ecological benefits; note that leaks from natural gas and oil production are a more significant contributor of atmospheric methane than cattle; see more on methane, cows and rotational grazing here, here, here, and here]
    • the highest-impact quintile consumed more than twice as many calories on a given day — 2,984 versus 1,323 — than those in the bottom 20 percent

    March 20, 2018 University of Michigan  Read full ScienceDaily article here

    See also InsideClimateNews article on this here

    On any given day, 20 percent of Americans account for nearly half of U.S. diet-related greenhouse gas emissions, and high levels of beef consumption are largely responsible, according to a new study from researchers at the University of Michigan and Tulane University.

    ….If Americans in the highest-impact group shifted their diets to align with the U.S. average — by consuming fewer overall calories and relying less on meat — the one-day greenhouse-gas emissions reduction would be equivalent to eliminating 661 million passenger-vehicle miles, according to the researchers—  nearly 10 percent of the emissions reductions needed for the United States to meet its targets under the Paris climate accord, the authors wrote…

    The highest-impact group was responsible for about eight times more emissions than the lowest quintile of diets. And beef consumption accounted for 72 percent of the emissions difference between the highest and lowest groups, according to the study.

    …Emissions related to the processing, packaging, distribution, refrigeration and cooking of those foods were not part of the study but would likely increase total emissions by 30 percent or more, Heller said….

    …. cows don’t efficiently convert plant-based feed into muscle or milk, so they must eat lots of feed. Growing that feed often involves the use of fertilizers and other substances manufactured through energy-intensive processes. And then there’s the fuel used by farm equipment.

    In addition, cows burp lots of methane, and their manure also releases this potent greenhouse gas.

    …They found that Americans in the highest-impact quintile consumed more than twice as many calories on a given day — 2,984 versus 1,323 — than those in the bottom 20 percent. But even when the findings were adjusted for caloric intake, the highest-impact quintile was still responsible for five times more emissions than the lowest-impact group.,,,

    Martin C Heller, Amelia Willits-Smith, Robert Meyer, Gregory A Keoleian, Donald Rose. Greenhouse gas emissions and energy use associated with production of individual self-selected US diets. Environmental Research Letters, 2018; 13 (4): 044004 DOI: 10.1088/1748-9326/aab0ac

  6. Norway is building some of the world’s first battery-powered ferries. Will they lead the way in cutting maritime pollution?

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    • Norway wants two-thirds of all boats carrying both passengers and cars along its jagged and windy Atlantic coastline to be electrified by 2030

    Mikael Holter and Jeremy Hodges, Bloomberg 
    …While progress in electrifying the world’s excessively polluting shipping fleets is miles behind advances in automobiles, Europe is making initial strides as Paris Climate Accord goals to cut carbon dioxide emissions loom large. Dozens of battery-powered boats that can move through inland waterways in Norway, Belgium and the Netherlands are about to make their first voyages, including some able to run fully automatically without a crew.Nowhere is this push more prevalent than Norway, a country where almost all electricity produced is hydropower, the state oil company is expanding into offshore wind farming and people drive more electric cars, per capita, than any country in the world. Next up, Norway wants two-thirds of all boats carrying both passengers and cars along its jagged and windy Atlantic coastline to be electrified by 2030. 

    Without big changes, the International Council on Clean Transportation warns sea transport could be responsible for 17 percent of CO2 emissions by 2050, up from 2-3 per cent now. But shipping was omitted from the Paris deal and battery technologies haven’t evolved enough for long ocean voyages, according to the International Maritime Organization, which is set to reveal in April an initial set of guidelines for cutting greenhouse gases….

  7. Cities Emit 60% More Carbon Than Thought

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    The carbon footprint of some of the world’s biggest cities is 60 percent larger than previously estimated when all the products and services a city consumes is included, according to a new analysis.

    The report was released Tuesday at the IPCC Cities and Climate Change Science Conference in Edmonton, Canada, and estimated the carbon emissions for the food, clothing, electronics, air travel, construction materials, and so on consumed by residents but produced outside city limits.

    The world’s cities emit 70 percent of the world’s carbon dioxide—and that’s likely higher when consumption emissions are included, says report author Michael Doust, program director at C40 Cities, a network of the world’s megacities committed to addressing climate change….

    …Wealthy “consumer cities” such as London, Paris, New York, Toronto, or Sydney that no longer have large industrial sectors have significantly reduced their local emissions. However, when the emissions associated with their consumption of goods and services are included, these cities’ emissions have grown substantially and are among the highest in the world on a per person basis, the report says. Meanwhile, “producer” cities in India, Pakistan, or Bangladesh generate lots of industrial pollution and carbon emissions in the manufacture of products that will be sold and consumed in Europe and North America….

    ..Cities that have high consumption-based GHG emissions are recommended to use consumption-based GHG inventories alongside their sector-based GHG inventories, or incorporate key supply chains into the latter. This would encourage more
    holistic GHG emissions assessments; enable decision-makers to consider a wider range of opportunities to reduce global GHG emissions; and provide an additional perspective with which to engage other stakeholders in climate action….

    C40 Cities. Consumption-based GHG emissions of C40 cities. March 2018.

     

  8. The World Is Embracing SUVs. That’s Bad News for the Climate.

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    By Hiroko Tabuchi Mar 3 2018 Read full NYTimes article here

    SUVs and “crossovers” made up more than one in three cars sold globally last year, nearly tripling their share from just a decade ago, according to a new report. Drivers in China, Australia and elsewhere are buying SUVs because of lower gas prices and higher incomes—which is slowing progress in reining in carbon emissions….

    …Between 2005 and 2008, the average fuel economy of new cars worldwide improved by about 1.8 percent a year, according to the United Nations’ Global Fuel Economy Initiative. But since then, that pace has slowed to 1.1 percent in 2015, the latest data available, far below the near 3-percent clip needed to simply stabilize emissions from the world’s car fleet….

  9. Suburban sprawl worse than urban growth for CO2 emissions

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    March 5, 2018 University of Utah Read full ScienceDaily article here

    Atmospheric scientists report that suburban sprawl increases CO2 emissions more than similar population growth in a developed urban core…

    …The research team concluded that population growth does not directly correlate with growth in CO2 emissions. Other factors, specifically the types of neighborhoods where population is growing, are much bigger factors.

    “In the more urban area, there’s population growth there, but it’s in the mature part of the city, not associated with growth in CO2,” Mitchell says. But it’s this population growth in rural areas that is seeing an increase in CO2 emissions. If you add more people into downtown Salt Lake City, they’re going into an existing place.”…

    Logan E. Mitchell, et al. Long-term urban carbon dioxide observations reveal spatial and temporal dynamics related to urban characteristics and growth. PNAS, 2018 DOI: 10.1073/pnas.1702393115

  10. Fertilized soil in the Central Valley produces 40% of CA’s nitrogen oxides emissions

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    January 31, 2018 UCDavis read full ScienceDaily article here

    A previously unrecognized source of nitrogen oxide is contributing up to about 40 percent of the NOx emissions in California, according to a new study. The study traces the emissions to fertilized soils in the Central Valley region….

    …Fossil fuels have long been recognized as a major contributor to NOx pollution. Technologies like the catalytic converter have helped greatly reduce NOx emitted from vehicles in urban areas. But some of the state’s worst air quality problems are now in rural areas, particularly the Central Valley region, which is home to some of the poorest communities in California.

    The Central Valley is also one of the world’s most highly productive agricultural areas. Roughly half of the fruits and nuts produced in the United States are grown there. This includes nearly all the nation’s almonds, walnuts, raisins, avocados, and tomatoes….

    ….“Only about half of the nitrogen fertilizer applied to crops are used by the plant. But slow-release fertilizers that deliver nutrients in a way that more closely mimics nature have been shown to greatly improve nitrogen use efficiency of crops, reducing emissions of nitrogen in the environment. Healthy soils programs that restore carbon in the soil can also help fight climate change and are likely to increase nutrient retention and cycling to crops….

    ….The state also began a program this year in which growers work in coalitions to gather information on efficient uses of nitrogen so they can evaluate how and where the state needs to manage nitrogen in agricultural areas. This work aims to reduce nitrate in the groundwater but it may have a double benefit in reducing NOx emissions.”…

    Maya Almaraz, Edith Bai, Chao Wang, Justin Trousdell, Stephen Conley, Ian Faloona, Benjamin Z. Houlton. Agriculture is a major source of NO x pollution in California. Science Advances, 2018; 4 (1): eaao3477 DOI: 10.1126/sciadv.aao3477