It is widely accepted that around 50 per cent of New Zealand's greenhouse gas emissions are from livestock, mostly in the form of methane and carbon dioxide.
Jacinda Ardern promises that a Labour government, under her leadership, would make farmers pay their fair share.
When defining that fair share, thefigure that needs to be used is not the quantum of the emissions, rather the net emissions after accounting for uptake. Ask the question, where do cattle get their emissions from, and a different picture arises.
When looking at this question, an overriding fact must be considered. The law of thermodynamics states that matter can neither be created nor destroyed. Modified, yes, created or destroyed, no.
Ruminant livestock get the emitted gasses from what they eat. In New Zealand in the main that is pasture. Photosynthesis, which uses carbon dioxide, water and sunlight to generate plant growth, is part of what is known as the carbon cycle, and it is closed.
Pasture providing nutrition to ruminants grows through photosynthesis. What is drawn from the atmosphere is returned to the atmosphere, modified but the same quantum.
Carbon dioxide returned becomes available for entering the carbon cycle immediately; methane, over a period, is converted back to water and carbon dioxide and is reused.
The net effect on the level of gasses (greenhouse gasses) containing carbon in the atmosphere is zero.
What is taken up in pasture growth is returned either from the bacterial activity in the ruminate's rumen, or by bacterial activity in the decomposition of plant material rotting. No gasses containing carbon returning to the atmosphere have not first come from there.
The burning of fossil fuels is a different and separate issue.
This clearly shows the fair share Jacinda Ardern is proposing can only be nil.
