The livestock sector could use almost half of the 1.5 degrees Celsius greenhouse gas emission budget allowed by 2030, so addressing this should be a key part of the strategy to hit climate targets, a new study said on Tuesday.

Farmed animal law and policy fellow Helen Harwatt at Harvard Law School advises that getting protein from plant sources instead of animal sources would drastically help in meeting climate targets and reduce the risk of overshooting temperature goals.

For the first time, Harwatt proposes a three-step strategy to gradually replace animal proteins with plant-sourced proteins, as part of the commitment to mitigate climate change.

These are acknowledging that current numbers of livestock are at their peak and will need to decline.

Set targets to transition away from livestock products starting with foods linked with the highest greenhouse gas emissions such as beef, then cow’s milk and pork.

The best available food approach is assessing suitable replacement products against a range of criteria, including greenhouse gas emission targets, land usage and public health benefits.

In the study published in Climate Policy, Harwatt further elaborates that recent evidence shows, in comparison with the current food system, switching from animals to plants proteins could potentially feed an additional 350 million people in the US alone.

Previous studies suggested reducing meat and dairy consumption also provides a range of added benefits such as preserving biodiversity and improving human health.

The article reports that the current livestock population in the world is around 28 billion animals and constitutes the highest source of two major greenhouse gases — methane and nitrous oxide.

The production of methane in particular is troublesome, as it has an 85 times greater global warming potential than carbon dioxide over a 20-year timeframe.

Methane emissions from the livestock sector are projected to rise by 60 per cent by 2030 — the same time period over which strong and rapid reductions are needed.

“Given the livestock sector’s significant contribution to global greenhouse gas emissions and methane dominance, animal to plant protein shifts make a much-needed contribution to meeting the Paris temperature goals and reducing warming in the short term, while providing a suite of co-benefits,” Harwatt added.