California’s cattle and dairy and cattle farms produce large amounts of methane, a greenhouse gas 80 times more potent than carbon dioxide over time.

UCSC science journalism lecturer Peter Aldhous on why Santa Cruzans should care about cattle, dairy pollution

For folks living in Santa Cruz County, the closest cattle and dairy farms are as much as two hours away. Still, the amount of greenhouse gas emissions produced on those farms, and thousands of others across the country, contribute to climate change, which itself contributes to a higher frequency of environmental disasters across the planet, and likely in Santa Cruz County. Hillary Ojeda interviews journalist and UCSC science communication lecturer Peter Aldhous about how state and federal rules fall short when it comes to tracking methane emissions from California’s largest cattle and dairy farms.

Many Santa Cruzans, and Californians, have the experience of driving by cattle or dairy farms and rapidly rolling up the windows or turning off the air conditioning to avoid the ripe stench of cow manure.

For folks living in Santa Cruz County, the closest cattle and dairy farms are anywhere from 1½ to 2 hours away, in the Santa Nella area, about 60 miles east of Watsonville — so it’s not an entirely common occurrence.

Still, the amount of greenhouse gas emissions produced by cow burps and manure on those farms, and thousands of others across the country, contribute to climate change, which itself contributes to a higher frequency of environmental disasters across the planet, and likely in Santa Cruz County.

Peter Aldhous, a UC Santa Cruz science communication lecturer since 2007, co-authored an article this month about how dairy and cattle farms — which produce methane, a greenhouse gas 80 times more potent than carbon dioxide over time — are given a “pass” by state and federal regulators as individual farms not required to measure and provide data on how much methane they produce.

Working with nonprofit coalition Climate TRACE, Aldhous and two other reporters show that it’s possible to measure methane at the facility level, but that regulators exempt agricultural sites from reporting requirements — unlike other industries such as natural gas utilities. Methane emissions from cattle and dairy farms as a whole are added to state and federal emissions estimations, but not at a facility level.

“Agriculture is a significant source of greenhouse gas emissions, and if we’re going to have accountability and try to reduce that, you need to measure it,” Aldhous said.

Using a method developed by Climate TRACE, the reporters found that a 643-acre feedlot in Southern California’s Imperial Valley is the “is the largest single source of methane emissions in the state, releasing more of that greenhouse gas than any oil or gas well, refinery or landfill.” The findings point to the importance of measuring methane emissions from industrial livestock operations known as concentrated animal feeding operations, or CAFOs.

Aldhous talked with Lookout last week about this project. He lives in San Francisco and, in addition to his UCSC position, is a freelance journalist. Originally from the United Kingdom, he moved to the Bay Area in 2005 to serve as the San Francisco bureau chief for science magazine New Scientist.

In the UCSC Science Communication Program, he teaches investigative reporting and data visualization and will start a news feature writing class next month as well.

This interview has been edited for clarity and length.

Lookout: What are the top takeaways from your reporting on CAFOs? And why is this story so important to report on right now?

Peter Aldhous: Agriculture is a significant source of greenhouse gas emissions. It is not at the moment as well documented and accounted for and regulated as other sources like electricity power generation. But if we are to deal with this very complex problem of greenhouse gas pollution and climate change, we’ve got to address it across the board. Accountability, and actually trying to estimate the emissions, not just overall, but the level of individual operators — so individual dairies and cattle feedlots — is going to be very important.

And right now we are in a climate crisis. Overall emissions have to come down by a lot to get anywhere near limiting the amount of global warming to manageable levels. Methane is arguably the highest priority because on a short-term basis it is a much more powerful greenhouse gas than is carbon dioxide. If we’re going to make rapid progress on reducing emissions, methane is a really good one to target. And there are ways to reduce these emissions. You can manage cattle manure in different ways. Or you can capture the methane from those emissions. There are also things that are not widely applied yet. But there are additives you can add to cattle feed that will reduce the amount of methane they burp up. Things like seaweed can be added to cattle feed that can do this. So it’s not only a significant contributor to global warming, but also it’s one where some real progress could be made quite quickly, that would make a noticeable difference.

Lookout: Does your reporting on CAFOs come close to having an impact on Santa Cruz County and if so, how?

Aldhous: I think in terms of direct relevance to Santa Cruz, this isn’t kind of a local issue, right? It’s a state issue, not a local issue. ... But if we’re talking about direct emissions in agricultural production, worldwide, something like up to 15% [of total global greenhouse gas emissions come from agriculture].

There are two major parts of that. One is methane emissions from livestock, which is what the story is about. The other one is emissions of a gas called nitrous oxide from fertilizers put onto soils, because what happens there is the fertilizers get broken down by microbes and release this greenhouse gas called nitrous oxide. So those are the two main reasons that you get quite a lot of emissions from agriculture. And the fertilizer one would be a thing once you get into around Watsonville and down into Monterey County and into the Salinas Valley — fertilizers would be quite significant, I think in terms of greenhouse gas emissions, but that’s not what our story was about.

Lookout: Are there other environmental issues in Santa Cruz County that aren’t regulated?

Aldhous: Obviously an important one everywhere, but I think there are a fair number of people now who commute from Santa Cruz County to Silicon Valley. If you’re using gas in your car, then that’s a significant source of emissions. I think providing the infrastructure to allow people to switch to electric cars is an important issue.

The other thing I’d always think about is the impacts, right? Because nowhere on the planet really is going to escape the escalating impacts of climate change. As the world gets hotter, extremes get more extreme. It’s difficult to know exactly what is going to happen. Everywhere, including Santa Cruz County, is going to be in for a difficult few decades. And how difficult it gets is partly in our own hands.

[Fertilizer] I believe it isn’t tracked at the facility level, but again, it should be fairly possible to estimate it as long as there is an inventory of how much fertilizer is being applied. If you’re thinking about trying to reduce it, you would be thinking about agricultural methods that can allow more limited fertilizer applications. I haven’t looked at that in detail, yet. I can’t really comment further than that.

Lookout: How do you respond to people here who say this doesn’t affect them because there are no massive cattle farms in Santa Cruz County?

Aldhous: The trouble is climate pollution is quite different from other forms of pollution. If we’re talking smog from traffic in Los Angeles, that’s primarily a local problem, right? You can live in Santa Cruz [and] not worry about how polluted the air is in Los Angeles. But climate is global. The sources of the emissions are in one place, but methane gets into the atmosphere and warms the entire globe.

I know we sort of say all news is local, which, on some level is true, but if we consider climate pollution, the local is global, so it doesn’t matter if the emissions aren’t happening on your doorstep, they are affecting you.

As the planet warms we know, sadly, from this summer that we are getting more extreme events. The middle of the U.S. is at the moment under this huge heat. We just had an unprecedented tropical storm hit in Southern California. Nobody really escapes the effects of climate pollution. And what we’re seeing now is only the start of what’s coming.

Our choice really is how bad is this going to get? The answers to that question are, well, what are we going to do to reduce this climate pollution?

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