Kat Kerlin, UC DAVIS NEWS
Eating Too Much Protein Adds to Nitrogen Pollution in U.S. Waters
…when a body takes in more protein than it needs, excess amino acids break it down into nitrogen, which is excreted mostly through urine and released through the wastewater system. This brings additional nitrogen into waterways, which can result in toxic algal blooms, oxygen-starved “dead zones” and polluted drinking water.
Balancing how much protein you eat with the amount your body needs could reduce nitrogen releases to aquatic systems in the U.S. by 12% and overall nitrogen losses to air and water by 4%, according to a study from the University of California, Davis.
Protein consumption in the United States, from both plant and animal sources, ranks among the highest in the world. The study, published in the journal Frontiers in Ecology and the Environment, said that if Americans ate protein at recommended amounts, projected nitrogen excretion rates in 2055 would be 27% less than they are today despite population growth.
The study is the first to estimate how much protein consumption contributes to excess nitrogen in the environment through human waste. It also indicates that coastal cities have the largest potential to reduce nitrogen excretions headed for their watersheds.
“It turns out that many of us don’t need as much protein as we eat, and that has repercussions for our health and aquatic ecosystems,” said lead author Maya Almaraz, a research affiliate with the UC Davis Institute of the Environment. “If we could reduce that to an amount appropriate to our health, we could better protect our environmental resources.”
Read more at https://www.ucdavis.edu/climate/news/balancing-protein-your-diet-could-improve-water-quality
Fiona Harvey and Giles Tremlett, THE GUARDIAN
Global greenhouse gas emissions must peak in the next four years, coal and gas-fired power plants must close in the next decade and lifestyle and behavioural changes will be needed to avoid climate breakdown, according to the leaked draft of a report from the world’s leading authority on climate science.
Rich people in every country are overwhelmingly more responsible for global heating than the poor, with SUVs and meat-eating singled out for blame, and the high-carbon basis for future economic growth is also questioned.
The leak is from the forthcoming third part of the landmark report by the Intergovernmental Panel on Climate Change, the first part of which was published on Monday, warning of unprecedented changes to the climate, some of them irreversible. The document, called the sixth assessment report, is divided into three parts: the physical science of climate change; the impacts and ways of reducing human influence on the climate.
Part three is not scheduled to be released before next March, but a small group of scientists decided to leak the draft via the Spanish branch of Scientist Rebellion, an offshoot of the Extinction Rebellion movement. It was first published by the journalist Juan Bordera in the Spanish online magazine CTXT.
Bordera told the Guardian that the leak reflected the concern of some of those involved in drawing up the document that their conclusions could be watered down before publication in 2022. Governments have the right to make changes to the “summary for policymakers”.
Read more at https://www.theguardian.com/environment/2021/aug/12/greenhouse-gas-emissions-must-peak-within-4-years-says-leaked-un-report
Robin KcKie, THE GUARDIAN
Attempts to solve the climate crisis by cutting carbon emissions from only cars, factories and power plants are doomed to failure, scientists will warn this week.
A leaked draft of a report on climate change and land use, which is now being debated in Geneva by the Intergovernmental Panel on Climate Change (IPCC), states that it will be impossible to keep global temperatures at safe levels unless there is also a transformation in the way the world produces food and manages land.
Humans now exploit 72% of the planet’s ice-free surface to feed, clothe and support Earth’s growing population, the report warns. At the same time, agriculture, forestry and other land use produces almost a quarter of greenhouse gas emissions.
In addition, about half of all emissions of methane, one of the most potent greenhouse gases, come from cattle and rice fields, while deforestation and the removal of peat lands cause further significant levels of carbon emissions. The impact of intensive agriculture – which has helped the world’s population soar from 1.9 billion a century ago to 7.7 billion – has also increased soil erosion and reduced amounts of organic material in the ground.
In future these problems are likely to get worse. “Climate change exacerbates land degradation through increases in rainfall intensity, flooding, drought frequency and severity, heat stress, wind, sea-level rise and wave action,” the report states.
Read more at https://www.theguardian.com/environment/2019/aug/03/ipcc-land-use-food-production-key-to-climate-crisis-leaked-report
Karin Brulliard, THE WASHINGTON POST
Gregory Okin is quick to point out that he does not hate dogs and cats. Although he shares his home with neither — he is allergic, so his pets are fish — he thinks it is fine if you do. But if you do, he would like you to consider what their meat-heavy kibble and canned food are doing to the planet.
Okin, a geographer at UCLA, recently did that, and the numbers he crunched led to some astonishing conclusions. America’s 180 million or so Rovers and Fluffies gulp down about 25 percent of all the animal-derived calories consumed in the United States each year, according to Okin’s calculations. If these pets established a sovereign nation, it would rank fifth in global meat consumption.
Needless to say, producing that meat — which requires more land, water and energy and pollutes more than plant-based food — creates a lot of greenhouse gases: as many as 64 million tons annually, or about the equivalent of driving more than 12 million cars around for a year. That doesn’t mean pet-keeping must be eschewed for the sake of the planet, but “neither is it an unalloyed good,” Okin wrote in a study published this week in PLOS One.
“If you are worried about the environment, then in the same way you might consider what kind of car you buy … this is something that might be on your radar,” Okin said in an interview. “But it’s not necessarily something you want to feel terrible about. ”
Read more at: The hidden environmental costs of dog and cat food – The Washington Post
Tim Radford, CLIMATE NEWS NETWORK
US-based research has found that even a modest switch to a more vegetable-based diet could lead to a significant reduction in greenhouse gas emissions.
Scientists have worked out how to combat climate change and improve human health, one mouthful at a time.
The answer is a familiar one: they calculate that a relatively modest switch towards a more vegetable-based diet could, in the US at least, lead to a reduction of 222kg in greenhouse gas emissions per person per year, while cutting the relative risk of coronary heart disease, colorectal cancer and type 2 diabetes by 20% to 40%.
It could also reduce US healthcare costs by at least $77bn a year and possibly $93bn.
The US spends $3tn on healthcare every year – 18% of gross domestic product – and a significant proportion of health costs are associated with obesity and illnesses linked to diet.
Read more at: Healthy diet good for climate change – Climate News NetworkClimate News Network