In findings commissioned by the European Dairy Association (EDA), methane emissions from dairy cattle were found to have increased steadily over the twentieth century ahead of global milk production levels.
This pattern occurred despite recent falls in the industry’s greenhouse gas output, the report claims.
Emissions study
As part of the report’s findings, which were compiled by independent consultancy CE Delft, researchers focused on greenhouse gas output from across three different points in the milk supply chain.
Amidst efforts by the entire dairy industry to drive both cost and environmental sustainability in their operations, life cycle assessments offer a potential means of assessing the environmental impact of producing milk.
However, DE Delft claims that attempts to compare data on how milk production at farm, cradle-to-farm-gate and prior to consumption levels impact greenhouse gas output needs revising to improve understanding of key environmental areas.
According to the report, the establishment of general standards for performing life cycle assessments of milk production can help farmers and manufacturers to improve methods of cutting greenhouse gas emissions.
In the findings of the EDA report, despite a surge in methane output over the last century, between 1990 and 2005, there were some noted improvements in the industry’s contributions to greenhouse gas output through milk.
“[Over the period,] the emissions from enteric fermentation in dairy cattle and those due to manure handling lowered respectively by 30 per cent and 20 per cent,” stated the report.
Compiling difficulties
Despite these findings, the report stresses that both methodological and regional variances in compiling milk life cycle assessments makes it difficult to provide direct comparisons in establishing the potential impact of dairy production on climate change.
“Ideally a series of consistent life-cycle assessments with a large variation of parameters would need to be performed,” the report stated.
US studies
Earlier this month, findings from the University of Illinois suggested that since 1944, the number of dairy cows and their equivalent methane emissions in the US have fallen from 25.6 million animals to 9.2 million.
Conversely, the report states that milk production was up over the same period to 186bn pounds (lbs) from 117bn lbs.
Ensuring more direct comparisons between milk lifecycle assessments may be vital in the global dairy industries drives to play up the environmental sustainability of its operations.
This has become particularly important amidst some criticisms of the environmental impact of dairy production.
Eco-attacks
Sustain, which claims to be an alliance for sustainable food production, earlier this year called for a choice-edit system of menus and food offerings in a bid to cut the carbon footprint of what we eat, targeting dairy and other livestock industries as key contributors to greenhouse gas emissions.
Citing published United Nations figures, the group said that animal farming has led to the creation of more greenhouse gas emissions than all cars, lorries and planes in the world combined.
Sustain claimed that this was related to a number of factors including the large amounts of animal feed required for production of a small amount of meat or milk.
Concerns over converting forest areas into dairy farm pasture have also been expressed by environmental groups such as Greenpeace, which earlier in the year attempted to reforest part of a New Zealand government-owned dairy farm.
The organisation said that the action was an attempt to raise awareness of its concerns over intensive dairy farming in the regions of the Central North Island and Canterbury.