Greenpeace has called for a halving of global production of meat and dairy by 2050 and an end to polluting industrial farming practices.

It said this week in a statement that such practices were coming under increasing scrutiny by New Zealand's international customers.

Greenpeace sustainable agriculture campaigner Gen Toop said: "If this is ignored ... the imminent consumer shift away from industrial meat and dairy products could present a major threat to our economy."

Greenpeace last night released a document it says exposes the "catastrophic environmental impacts of industrial meat and dairy farming".


But Dr Jacqueline Rowarth, who was until last week chief scientist of the Environmental Protection Authority, says Greenpeace's report may be correct for America but it doesn't apply to New Zealand.

Dr Rowarth spoke to The Country's Jamie Mackay today about the report saying, "Of course a Greenpeace document which came out of the Northern Hemisphere is covered with pictures of feedlot farming and barns and we don't do that."

As for greenhouse gases, Dr Rowarth says New Zealand is at best practice for milk and meat and it is less-developed countries that are producing far more GHG than the pasture-based agriculture here.

"What always bothers me about reports like this is that people immediately say 'Oh New Zealand's got to clean up its act,' whereas in comparison with what the report is saying - we already have."

Listen to the full interview below:

The Greenpeace report says agriculture, left unchecked, is projected to produce more than half of all global greenhouse gas emissions by 2050, 70 per cent of which would come from industrial livestock. It said livestock farming is responsible for 14 per cent of global climate change emissions - as much as all trains, ships, planes and cars put together.

"Greenpeace in New Zealand has been campaigning against the industrial farming practices that have taken hold here. These include intensive stocking, the heavy use of big irrigation, synthetic fertilisers, toxic agri-chemicals and imported animal feed," said Toop.

"Fortunately, we also have a growing number of meat and dairy farmers in New Zealand that have reduced their herds and turned their backs on industrial practices - working with the environment rather than to its detriment."

"This report puts those progressive, regenerative farmers in a prime position to take advantage of this new global playing field."