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by schiffern 3269 days ago
The catch is, modern agriculture isn't limited to "surface-level biology."

>All of the carbon you exhale to the atmosphere comes from the food you eat, which gets its carbon from the atmosphere via photosynthesis.

This is true, but also misleading. When you include the nitrous oxide, methane, diesel fuel, and loss of soil carbon, agriculture is actually net CO2e positive.

>Agriculture, Forestry, and Other Land Use (24% of 2010 global greenhouse gas emissions): Greenhouse gas emissions from this sector come mostly from agriculture (cultivation of crops and livestock) and deforestation. This estimate does not include the CO2 that ecosystems remove from the atmosphere by sequestering carbon in biomass, dead organic matter, and soils, which offset approximately 20% of emissions from this sector.

So in other words, globally our agriculture emits 5 units of CO2e for every 1 unit sequestered by photosynthesis.

https://www.epa.gov/ghgemissions/global-greenhouse-gas-emiss...

https://www.eia.gov/environment/emissions/ghg_report/ghg_nit...

When you include the entire supply chain from field-to-fork (agriculture, transport, refrigeration, processing, preparation) the general rule of thumb is that 10 kilocalories of fossil fuel energy go into making 1 kilocalorie of food.

https://blogs.scientificamerican.com/plugged-in/10-calories-...

2 comments

Great information here. This is well understood on my end. I just wanted to make a quick point because the topic was on food consumption and I don't think many people ever truly connect the dots between carbon atoms in the atmosphere -> carbon atoms in their salad -> carbon atoms in their breath (atmosphere).
Indeed, and I should have been clear that I was elaborating on your excellent post, not suggesting any error/omission/ignorance on your part. My intent was to comment on the idea ("if you just consider this one fact, it could be misleading"), not to say anything negative about you personally. My apologies that it came across that way.

So no worries, and no criticism intended. After all, how could anyone say everything that's possibly relevant in one comment? And more to the point, why in hell would anyone want to? :)

So you agree that engine emissions are the problem then, good.
I'm sorry, you lost me. What do you mean?

It is undeniable that transportation is a major contributor to the greenhouse catastrophe, accounting for 27% of U.S. emissions and 14% of global emissions.

I'm a huge proponent of electric cars and solar panels, but let's not kid ourselves that they'll solve climate change all by themselves. Those are necessary, but not sufficient. We also need to figure out how to grow food without long-term desertification of the continent.