New research has shown that the methane emissions have been rising at a much faster rate than carbon dioxide -  over the last 250 years, CO2 has increased by 31% but methane has increased by a staggering 149%. As methane lasts longer in the atmosphere it also has a higher global warming potential and has already caused a fifth of the global warming experienced since 1750.

The university of Portsmouth found that a herd of 200 cows produce annual emissions of methane equivalent to driving a family car more than 100,000 miles (180,000km) on more than four gallons (21,400 litres) of petrol.

The main source of methane? Animals.

It’s no wonder the National Farmers’ Union is getting a little nervous, they have already stated that the new targets for 80% cut in greenhouse gas emissions will make it neccessary for massive reductions in meat production. This new research is not going to do them any favours.

Japanese company Idemitsu Kosan Co is currently researching the benefits of oil from cashew nut shells in reducing the amount of methane produced by cows. Apparently, adding the oil to feed can reduce the methane emissions by 90%.

There is an obvious flaw in the plan. There are currently around 1.5 billion cows in the world. If this oil from cashew nuts really works and catches on, can you imagine how much would be needed for so many cows? Cattle ranching, and forest clearing to make way for crops which we predominantly feed to animals, is already the top cause of deforestation. Our current level of consumption of cashew nuts would not provide enough shells to produce the oil to feed 1.5 billion cows, therefore introducing cashew nut oil to feeds will only lead to more destruction as we clear more forest to make way for cashew trees.

Cashew nuts can only be grown in a warm and humid climate: ie the South. Amongst the top 5 cashew producing countries are Indonesia and Brazil - two countries which are already facing devastating levels of deforesation to make way for cattle grazing and crop planatations to feed animals or to produce biofuels. If we increase the demand for cashew nuts, we will see further deforestation.

Besides methane and deforestation, we also have to consider the other impacts of the meat and dairy industry - water use (it takes 990 litres of water to produce one litre of milk, 10,000 to produce 1kg of beef), water pollution, land degradation, ammonia… And these impacts could double by 2050 if we don’t do something about it now (2).

There really is just one ethical, sustainable, realistic answer to the enormous impacts of the livestock sector, and that is to end it. If we carry on consuming meat at the current level, and countries like India and China continue increasing their consumption, we will never be able to stop deforestation, world hunger or climate change.

The BBC’s Countryfile today discussed the issue of cows and sheep and methane. 90% of the methane produced by animal agriculture comes from the cows and sheep themselves. So what can be done to reduce the amount of methane, which is 23 times more damaging to the planet than carbon dioxide?

Well, of course, the solution is simple. Less cows = less methane. Less meat … less cows! However, the farmers think otherwise.

Aberystwyth University and the Institute of Grasslands and Environmental Research are now researching diet changes for cows that will reduce the amount of methane they produce. Apparently garlic and essential oils can reduce methane as can certain types of grass. They predict a reduction of around 30%.

However, they are somewhat missing the point here. By 2050, scientists predict that our meat consumption will grow by 50%. We are already at a point where climate change is critical, as is deforestation, water scarcity and land degradation (all of which the meat industry impacts significantly). For our survival we cannot let the situation get any worse - we cannot allow this 50% increase in meat consumption to occur. Where do people think we can raise 50% more animals? Giving cows a few essential oils is just a drop in the ocean and a waste of time.

Farmers in New Zealand now have an added incentive to switch from animals to growing crops. Levels of methane and nitrous oxide emitted from farms (from cows and sheep) will soon be capped, forcing farmers to find ways to reduce the levels.

Farmers could offset methane and nitrous oxide through emissions trading or planting trees, but these schemes are frowned upon by many environmental organisations as they are not seen to be a solution to the problem.

Attempts to reduce the amount of methane that cows and sheep produce through diet have so far only resulted in inconsequential reductions, so farmers will need to consider bigger changes - such as switching to growing crops!

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