California’s strategy to reduce super pollutants from dairy

Signal of change / California’s strategy to reduce super pollutants from dairy

By Ali Silk / 18 May 2017

The California Air Resources Board has released their ‘Short-Lived Climate Pollutant Reduction Strategy’ for reducing the state’s emissions of short-lived greenhouse gases like black carbon, hydrofluorocarbons and methane, that contribute to climate change.

This new strategy is in response to law SB 1383, signed in September 2016 by California’s Governor Brown. Its successful implementation will meet the required 40% reduction of methane by 2030 from 2013 levels. The plan needs to be implemented by January 2018.

So what?

California isn’t just a producer of fruits and vegetables - most notably almonds and avocados. The state is also home to the most dairy cows in America, with 1.7 million milking animals, alongside the nearly four million cattle bred there for beef. With California generating the most revenue of all states from milk, at $6.9 billion, dairy is an important business, but not one without its challenges.

Agriculture represents the largest source of methane in California, producing nearly 60% of the emissions, with organic waste sent to landfill contributing a further 20% of emissions. The remaining roughly 20% comes from oil and gas extraction, pipeline leakage and industrial activities.

Breaking this down further, dairy cows alone produce 45% of California’s methane emissions; 25% of which is from manure, and 20% from dairy enteric emissions – the cows’ digestive gases.

The strategy aims to reduce emissions by encouraging innovation around waste, including composting and anaerobic digestion of organic waste for biogas, and manure management. $50 million is due to be spent by the government on pilot projects like farm-based methane digesters. Progress will entail financial incentives, State and private sector collaboration to overcome barriers, the development of policies to encourage renewable natural gas production, and other market support.

Methane produced through enteric fermentation from livestock is a critical source to reduce, but effective control causes concern for farmers. One solution may involve animal dietary changes, but this would only be viable without an impact on milk production, costs or animal health. Breeding animals for less methane production or intervening in gut microbes could be potential alternatives. Though not currently a viable option, could fart backpacks for cows be an answer in the future?

For farmers, concerns lie around the financial implications: whether regulations will mean they are forced to build new waste management systems or install anaerobic digesters on their farms, both prohibitively expensive options for most. Whilst pasture-raising cattle can reduce manure, this is impractical for many dairy farmers, and more so as the state faces further drought. The big question will be how to achieve targets without reducing the numbers of cattle owned.

Once approved, these new rules won’t go into effect until 2024. Even then, if in 2020 the 40% reduction isn’t deemed economically or technologically feasible, or energy infrastructure and market demand is lacking, the 40% goal could be reduced. Ultimately, no action can be taken if it hurts the public perception of milk.

This being the case, it remains to be seen what impact this new strategy will have, both on methane emissions and the future of dairy farming, both in California and outside.

Will this mean that Californian dairy moves into other states with less restrictive regulation, simply moving the problem elsewhere?


What might the implications of this be? What related signals of change have you seen?

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