Climate Change: Make the dairy industry pay their way

The dairy industry is celebrating its biggest payout ever: $13 billion. Which is great for the farmers, but immediately raises the obvious question: if they're so rich, why aren't they paying their way? Because dairy farming relies on enormous water and carbon subsidies from everyone else, and it is neither fair nor just that we should be expected to subsidies their profits through environmental degradation.

Can they afford it? Hell yes. Using the annual NZ Dairy Statistics and Greenhouse Gas Inventory you can calculate the amount of methane emitted per kg of milk solids: 0.251 kg. That turns into 7.028 kg of carbon dioxide-equivalent using the AR5 GWP₁₀₀ of 28 (or 21.084 kg using the arguably more appropriate GWP₂₀). Which at $65 / ton means about $0.46 (or $1.37) per kg of milk solids. Which they can currently easily afford on the current midpoint payout of $8.40. So why are we being expected to subsidise them again?