1. Terrapass’s big moment in the sun was when they issued carbon offset certificates for the gift bags at the Academy Awards in 2006, the year An Inconvenient Truth won its Oscar for Best Documentary Feature.

2. This assumes that people, knowing that restaurants are especially offensive planet warmers, would choose to cook at home instead. It’s admittedly something of a big assumption, as a great many of us continue to do things like eat bluefin tuna knowing full well that it couldn’t be worse, ecologically speaking.

3. Not included in the study, either due to time and data constraints or because their expected value was de minimus, were emissions associated with: wastewater treatment; hauling of restaurant laundry; employee commuting; water-filter delivery services; restaurant maintenance; water as an ingredient; distribution vehicles supplying the grocery store; home laundry; home garbage disposal (food scraps were composted); food waste in production of the home meal; production of gelatin, fat powder, and modified starch glucose (there was a lack of data, but these ingredients were used in negligible amounts).

4. The anaerobic bacteria that decompose ­organic waste in landfills produce methane gas as they work. Composting bacteria (aerobic decomposition) do not.

5. Noma’s kitchen is all electric and responsible for an average of 3,193 kg CO2e per week. Prime Meats’ combined gas and electricity use produces 3,468 kg CO2e per week. This doesn’t necessarily mean the two restaurants use the same amount of energy, though. Different power grids vary in how cleanly they produce energy. New York City has a cleaner power grid than Copenhagen. (Peter was surprised by just how dirty Dong Energy—Denmark’s largest power company—is, considering what a forward-thinking part of the world it serves.) My kitchen, where I cooked the home meal, is located in the cleanest power grid of the three, San Francisco, and brings about 2 kg CO2e into existence per week as a result of gas and electricity use.

6. This goes back to my point about perception. It’s easy to look at the bullet points about a restaurant like Noma—three consecutive years on top of the World’s 50 Best Restaurants list; René’s assured, progressive philosophies; the vegetable-centric menu; the foraging; the symposium—and assume that it must be the outright leader in all manners of earth friendliness. To wit, Kate Krader, the restaurant editor of Food & Wine posted a photo of our carbon study results on Instagram and asked “home cook vs @noma vs @frankiesspuntino meal, which has the highest CO2 level? Guess.” to which one of her followers responded “Am I mis-reading something? It looks like Noma. How do they come up with the numbers?”

7. For the record, Noma already uses some of the most energy-efficient equipment available.

8. Special commendation should go to Zuzi Otcenasova, the Noma staff member tasked with gathering information on two separate 400-ingredient menus, 27 delivery companies, plus electricity, waste-collection, and laundry bills.

9. When I asked Peter what sorts of projects might fit this description, he sold me on the idea of anaerobic digesters. In the most reductive terms, anaerobic digesters capture the methane from animal waste, recycle it as natural gas that can be used to cook or heat a home, and render the animal waste safe to be used as fertilizer. Because methane is a potent greenhouse gas, small projects can have a big impact. For example, in the developing word, $150,000 could buy and install 750 small digesters providing energy for households and reducing greenhouse gas emissions by around 2,500,000 kg CO2e each year.