By now you must have heard that cows are responsible for for more than 50% of the greenhouse gas emissions I decided to have a closer look. A little navigation if you keep reading :

I delve in to look at What Resources Cows Use – including water.

I move onto describe How Amazon Deforestation Is Directly Linked to Cows?

Then I proceed to the cause dearest to my heart : Ocean Deadzones due to Animal Agriculture.

Then I dissect What Emissions Do Cows Cause? Why do they burp so much? Which Gases are the most harmful to our planet?

Finally, I touch upon some potential Solutions to this Crisis – including new discoveries and what YOU can do!

So lets get started by looking at :

Our Earth’s Current State

The United Nations report has identified the world’s rapidly growing herds of cattle as the greatest threat to our earth. The cattle herds and the amount of resources they require are endangering the climate, forests, marine and land life. But how exactly are cows responsible for all of this? I am going to breakdown what makes cows exactly so destructive to ecosystems.

I have always considered myself an environmentalist, from a young age proudly telling my mother the new earth-friendly techniques that my school encourages. I am certain many if not all of you have heard the same thing, recycle the paper, switch to eco friendly light bulbs, turn off your tap between wetting and rinsing your toothbrush, avoid palm oil, ride your bike and turn off your lights. It always seemed to stop there though. Our teachers, school, government country, always said that if we practised these behaviours we were being good, green citizens. Just look at what the World Wildlife Fund (WWF) writes as methods to reduce your impact. (no mention of decreasing meat consumption)

Is it enough though? The Climate Change council just announced an irreversible level of carbon dioxide in our atmosphere : 440ppm. The safe assumed number is far lower in the 350ppm. The earth is projected to warm by as much as 5-7 degrees as found from a paper published in Nature. So if I, my peers and thousands of people around the world implemented these Green Peace environmental friendly techniques, why is our earth suffering so much?

Gidon Eshel PH.D, a research professor in environmental physics who grew up raising and slaughtering cattle provided us with a very sobering message in Leonardo Dicaprio’s and National Geographic’s Before the Flood. ( I Highly recommend you check it out)

Beef has been the largest contributor to deforestation in the past fifty years. It is also one of the most inefficient uses of resources on this earth. An example often quoted is that in the USA 47% of land is used for food production. Out of this, 70% is used to grow feed for cattle. With the tiniest 1% growing the food we consume, such as fruit, vegetables and nuts.

Agriculture accounts for an enormous percentage of emissions, with the most conservative estimations at 18%. This is larger than the greenhouse gases caused by planes, cars and all other forms of transport added together. Mentioned or not, animal agriculture is an enormous and unspoken reason behind climate change. According to some of these numbers, it is the number ONE reason for deforestation, climate change, damage to marine and land life.


We need to protect the ocean habitats for these beautiful creatures!

So what is it about animal agriculture that makes it such a gigantic contributor to greenhouse gas emissions?

What Resources Do Cows Use?

Quite often, when people talk about meat, they forget that that meat was a living breathing cow. Now, I am not writing this to consider it’s feelings, rather just the basic requirements for it to survive until it is so unceremoniously chopped up and wrapped in plastic. Cows are enormous mammals, weighing around 750kg. It takes a beef cow around five years to reach its ‘harvestable age’ on a normal grass fed diet. However, in the beef industry nowadays cows are slaughtered at 14-16 months of age weighing around 500kg. This means for 1 year, the cow consumes around 20 litres of water and 14.5 kilograms of feed a day. Thats 7300litres of water and 5300kg of feed. This feed is mostly corn, some alfalfa mixed with liquified fat, protein supplements, liquid vitamins, synthetic estrogen, and antibiotics. Since the price of corn has recently risen, beef industries pump the cows with drugs which causes their metabolism to deposit protein instead of fat. This makes the cows weigh more and fetch higher prices at slaughter. There is a whole load of downsides with this that I will not get into more.

Here we will just compare the grain fed cows, (majority of the cows raised in America, Australia etc) and grass fed cows ( generally Europe or ‘organic’ labled cows from Australia and America.) Grassfed beef is generally never questioned about it’s environmental impacts. Feedlot beef was popularized because there was no effective way in raising cattle on grasslands.

Grain fed cows receive :

Out of the 500kg cow, only around 200kg can be used as retail cuts. So irrespective of their diet, a cow will use 7300 litres of water in it’s life time, which amounts to around 36 litres per 1 kg of usable meat.  Or 5.4 litres per 150g burger. Considering they eat 5300kg of feed, this translates to 26.5kg per 1 kg of meat. These numbers are the water and feed the cow consumes directly. If we were to multiply the 5300kg of feed, (assuming 1 kg of wheat or maize requires around 1200litres of water) this comes to  around 31,800 litres of water per 1kg of beef. Frequent estimates found by the UN and other prominent organisations have quoted a number of around 15,000 litres for 1 kg of beef. Either way, whatever math you do, beef is definitely a very inefficient way of feeding the human poulation.

Grass fed cows :

Many people I have met argue that they eat grass fed beef, which for some reason they consider more sustainable.  In reality, grassfeed cows require much larger pasture areas and take much longer to reach maturity. Some estimates show, that due to their slow growth up to 50% more greenhouse gas emissions are released than feedlot beef. In winter and during droughts, grass fed cows still depend on crop feeds. Farmers estimate that each cow requires from 2.5 to 30 acres of pasture depending on the quality of the pasture. these pastures often end up being areas of previous rain forest, cut down to make room for grazing cattle. If we take the conservative number of 2.5 acres and the 1.5 billion cattle in the world, that would amount to 15 175 711 km2 of grasslands to sustain that number. (and these are all the conservative estimates). The total area of the land on earth is 148,300,000 km2  . This just shows that grass fed beef is no way a more sustainable solution, especially if humans want to continue consuming meat at such a rate. So the problem for grassfed beef is we simply do not have enough planet for it to be a viable alternative.


Dairy cows:

They require 990-1020 litres of water to produce one litre of milk. This is based on various estimates : of course, the climate, local soil, irrigation techniques, type of cow are all factors creating error in that number. It is also dependant on what is meant by water. Green water is calculated as rain water primarily used for watering the pastures, blue water is taken from rivers while grey water is considered the amount of water polluted. (not quite 100% on that one). But if all the three are considered in providing drinking water, watering grass for consumption and as smaller percentage going towards cleaning milking stations etc. Either way, that is an extremely inefficient liquid producer! Especially considering we do not need cows milk. The dairy industry is pretty crazy for a variety of reasons, but I won’t get into that in this article. Cows can live up to 20 years through a healthy diet, while in the dairy industry they are considered spent and send to slaughter after four years.

On top of that, dairy cows (generally) live exhausting lives. Seems a bit unecessary for food we do not need to consume… and and many of us are intolerant to.

Cows and the Amazon

The Amazon is the reason behind the scientists coining the term “biodiversity”. The area is home to 10% of all plant and animal species known on earth. There is over 40,000 species of plants, 400 mammals, 1300 birds and over a million insects. The number one reason for the clearing of trees, and destroying native habitats is beef.

source :


One football stadium is cleared in the amazon every second. Clearing of the rain forest began in the 1960s and by 2016 has decreased the size of the amazon by 10%. In the time that you read these two sentences, the size of a football field area of rainforest has been chopped down. The cleared land is used primarily for cattle and soybean production, it however does not stay fertile for very long. This means that the local farmers have to continue clearing land for their productions. It’s hard to argue to completely stop deforestation, as thousands of people’s livelihoods depend on it.


source :


Along with the obvious decrease in available habitat for native wildlife to live in, the Amazon Rainforest is responsible in converting a large part of the world’s carbon to oxygen. We are killing the lungs of the earth at an alarming rate. Since trees absorb carbon dioxide, they store it for us as we continually pump more into the atmosphere. When trees are burned as they are cleared, they release the carbon they have absorbed back into the atmosphere.  The energy required to cut down the amazon, and the fewer trees left to convert carbon dioxide back into oxygen has caused a 1.5% rise in carbon levels since the 1960s. A study has shown that the Amazon has lost half of its ability to absorb CO2 as trees die.

Protests and petitions about stopping the deforestation of the amazon have existed as long as I can remember. How come no one has voiced the driving deforestation cause?

The Cows and the Ocean

Organisations like Sea Shepherd strongly promote veganism with the message of  If the Ocean’s die, we die. This is because the consumption of beef directly effects our oceans as well. To sustain such an incredible large number of livestock and to keep them disease free, farmers rely on large amounts of fertiliser, pesticides, antibiotics and hormones. The fertilisers overnourish nearby streams which feed into bigger rivers and oceans, all the while causing weeds to grow and unbalance the ecosystems in the water. The pollution from the run off ends up in the ocean creating enormous ‘dead zones‘. The Gulf of Mexico is a prime example of where the waste from the US beef production is carried down the Mississippi killing coral reefs and their inhabitants. This particular dead zone is 21,000sqkm.


Flinders Reef, Australia, 2013

Coral Reefs are extremely sensitive to changing chemical compositions in the water. While some corals are more hardy, many will die with even mild fluctuations in the pH of the water, abundance or lack of nutrients and a change of 1-2 degrees celcius. Since 1800, the oceans have absorbed 1/3 of carbon dioxide produced from human activities. As carbon dioxide in the ocean increases, ocean pH decreases or becomes more acidic. Reefs house enormous amounts of the biodiversity, and are responsible for a large part of the oxygen production. While the rainforests are responsible for 28% of oxygen production, the oceans emit 70% of the oxygen! If the oceans die, we die.

Over a quarter of the small scale fishermen depend on coral reefs, that is over six million fishermen in 99 reef countries and territories worldwide. If the Coral reefs die this will endanger, the livelihoods or so many people who contributed the least to the greenhouse gas emissions.

Coral Reefs

Great Barrier Reef 2014

Transport of food

What is often not included in the calculations of emissions from animal agriculture, is the transport of the product from the fields to the factories to the supermarket shelves. While yes, other types of food also create emissions if not purchased locally, that is one of the reasons I think shopping at farmers markets is so great. Meat is one of Australia’s largest exports, so if people are hating on Leonardo Decaprio for flying a private jet to accept an environmental prize, they should consider how far the food on their plate has voyaged.

Recent studies have shown that people who partake in the ‘locavore’ diet, that is focus on food which has been produced in their local environment, do decrease their carbon footprint. Just have a look here at the benefits of buying local. However, even people who buy locally and continue to purchase large amounts of meat, counteract the positive effect of local purchases of a month by one burger.

Buying local is always important, whether fruits, vegetables or indeed meat. It supports small farmers and does decrease carbon emissions.

Are Cows To Blame for Climate change?

To start, there is an enormous number of cows on this earth. 1.5 Billion cattle give or take recent estimations. Cowspiracy showed me some shocking facts a year ago. According to them, 13% of the Greenhouse gas emissions are from transportation while 51% is from animal agriculture. This seems like an incredibly large number to have kept from the masses for many years… so my scientific instincs tingling, I decided to look a little bit more into it.

The USA Environmental Protection Agency quotes agriculture to be at 9% and incorporating forestry and other land use that percentage rises to 24%.

This all seems far fetched from the 51% presented by Cowspiracy, why is this?

The Cows Anatomy

Cows emit methane from their farts and burps. Here is an example of how scientist collected methane that was emitted from cows. In one day this particular cow emitted 800-1000 litres of methane. The hectic backpack the cow is wearing below was developed by scientists to capture methane. So, lets say an average of 900 litres a day per cow, there are 1.5 billion cows. That is one trillion three hundred fifty billion litres of methane. ( I had to google that, and would have no idea how to write that in numbers).

Cows cannot help it though, their anatomy is very different from the humans therefore they are able to digest very different food to us. Grass, hay and other plant material cows consume have hard-to-digest cellulose. To be able to extract the necessary nutrients from the grass, cows have evolved a four compartment stomach. Cows are mammals which belong to a class of other four-compartment-stomached creatures including giraffes, sheep, goats and deer. The largest compartment in their stomach is named the Rumen in which millions of tiny organisms live inside and  help break down the plant matter into nutrients the Ruminants can digest.  While these microbes hang out and break down the grass and cud inside the cow’s stomach one of the byproducts released is methane.

90% of the methane released is from their burps, while 10% is from their farts.



How Bad Is Methane?

*warning* mild math ahead

One of the first things you read when cows are mentioned in the same sentence as emissions is their burps. Their wind and manure emit 1/3 of emissions of methane. Methane is the greenhouse gas no one mentions in their pretty pamphlets. Methane warms the world at a rate 20 times faster in comparison to carbon dioxide. Let me repeat that, for every molecule of methane it equates to 20 molecules of carbon dioxide. Why aren’t there campaigns to cut methane emissions down? Livestock also produce 100 other polluting gases, with 2/3 of the world’s emissions of ammonia. Ammonia is one of the leading causes of acid rain. Acid rain in turn attributes to significant endangerment of ecosystems by altering the chemical composition of the earth, slowly damaging and killing plant life.

Below is a piechart showing what the Environmental Protection Agency has published in 2014 based on data collected in 2010.


Source: IPCC (2014)

Looking at this emission chart, it says that 76% of the total greenhouse emissions are from Carbon Dioxide while 16% are of methane. The pie chart above demonstrates the percentage of gases emitted, however it does not take into account their GWP. Global Warming Potential (GWP) is a comparison of the global warming impacts of different gases. It is a comparison of how much energy the emissions of 1 ton of gas will absorb over a certain time period to the emissions of 1 ton of carbon dioxide. The greater the GWP the more a given gas warms the earth in comparison to carbon dioxide.

In the example below, I used the time period of 20 years and scaled the emissions from 2010 to incorporate the global warming potential. This is what came out :



Looking at his, Carbon Dioxide is not the greenhouse gas which we should be most concerned about. It is almost negligible. In the next twenty years, Nitrous Oxide will be responsible for 75% of warming, while methane of 18%. These are the two leading greenhouse gases attributing to climate change. Not the carbon dioxide from our vehicles. Both of these gases are major byproducts from the beef industry.

***Mind you, I created this pie chart from information provided to me by the Environmental Protection Agency from several years ago. I admit there may be huge margins of error : considering we do not know current emissions, we do not know exactly how much of these emissions have been reabsorbed by oceans or forests and there are probably several other factors I cannot possibly know since I have not been out in the field measuring all of these emissions myself. All I am trying to do, is gain a better understanding of the greenhouse gas emissions and what we can do.

So wait, wait, wait. I came into this thinking that Methane is the secret deadly gas. Is it actually the even more underground, unheard of gas : Nitrous oxide? Let’s have a look at what this means

What is Nitrous Oxide?

Nitrous Oxide is is usually known as laughing gas. I recently went to the dentist and experienced laughing gas for myself the first time. It was pretty great.

Nitrous Oxide is naturally found in the atmosphere as part of the nitrogen cycle. However in recent years human activities such as agriculture, fossil fuel combustion, wastewater management and industrial processes. Natural sources create 62% of total emissions while human related sources are responsible for 38%. Before the industrial revolution the atmospheric concentration stayed in the safe range due to natural sinks. However, now nitrous oxide levels are higher than in the previous 800,000 years. Below are the human sources putting nitrous oxide into the air found from here.

Nitrous Oxide Human Emissions

Agriculture is responsible of the 67% of the nitrous oxide emissions, with direct emissions of agricultural soils and livestock manure at 42% and indirect emissions from fertilizer run offs at 25%. Overall, agriculture creates 4.5 million tonnes of nitrous oxide per year. This means, out of the total 6% nitrous oxide emissions from all the greenhouse gas emissions 2.3% are manmade. Therefore if we separate the GWP for the nitrous oxide we would get something more like this:

gwp with nitrous oxide

Considering 48% of this nitrous oxide is from natural sources, we can assume that the warming effect of that nitrogen is counter balanced with re absorption back into the land as part of the nitrogen cycle. Currently if we consider our air, it is made up of 78% nitrogen, making it the most abundant molecule on our planet. The additional man made nitrous oxide escaping into out atmosphere however could have serious global warming effects.

What also needs to be considered is how long these gases remain in the atmosphere. Around 80% of carbon dioxide dissolves into the ocean between 20-200 years, methane takes merely 12 years while nitrous oxide persists for around 114 years. This would be one of the key reasons governments and scientists worry about carbon dioxide. While it does not have a warming potential as high as methane, it remains in our atmosphere significantly longer.

The only way to decrease nitrous oxide production, is to decrease agriculture.

Scientific Solutions to the Cow Burping and Farting problem :

Scientists have recently figured out that if you feed cows a particular type of algae, it actually cuts down their methane emissions. Algae are extremely adaptable organisms, capable of flourishing in everything from sewage, saline bodies of water and wastelands. Several studies were conducted to find that feeding ruminants algae could be an excellent supplement of protein. While the research is in experimental stages, a continuation down that path could result in commercial production of algal products. Algae is a much more sustainable alternative to corn, and could potentially decrease the amount of agriculture cow feeds would require.

I still am in wonder of the crazy things scientists devise: Rob Kinley has built an artificial cow stomach out of glass and tested the fermentation process of different algae. Out of the 20 types of seaweed, he found that the red seaweed off the coast of Queensland Australia had the most promising results. He continued onto feeding the seaweed in pellet form to sheep and found an 85% reduction in methane emissions. The research will soon continue onto cows with the potential of mass producing this seaweed. (even though the global amount of cows would require one million tonnes of it…) Here is one of the papers he published on the study, showing the results of 15 types of algae, some increasing the gas production and some decreasing it dramatically.


There is no black and white answer about whether cows cause climate change, luckily we are in the golden era of information. This article presented just a few of the findings from recent years.

However, if you do think the vast amount of cows are making our earth a little warmer, What Can We Do?

Simply put : Decrease the demand. That will result in a decrease in supply.

Predictions have been made that the demand for meat will double by the year 2050. This means that the already enormous number of 1.5 Billion Cows will continue rising.

Our earth cannot sustain this.

No matter how delicious the burger tastes, the price tag of it is becoming too hard to ignore. Between the rate of deforestation to grow the grain for the cows to eat. The methane farts which are 20 times more dangerous than carbon dioxide emissions. The ever increasing ocean deadzones threatening the balance of the seas.


The Oceans are too precious to lose.

The simple maths of our rapidly growing 7 billion population. I know the feeling that one meal will not change a thing. That one person cannot make a difference. But remember, for every meal you decide to skip meat is a tiny decrease in the demand. It is a wonderful opportunity to taste a myriad of the delicious plant based recipes. That one meal may turn to a day, a week or maybe a life time change. We will not see change if 3% of the population go fully vegan. The goal should be to have 60% decrease their meat consumption.

Meat in large amounts has been proved to cause Cancer, increase cholesterol and lead to a shorter life. The fact is, from looking at the evolution of the human diet and our human anatomy, we might not even need to consume meat to be healthy anymore.

So why not give your body some love? Why not try decrease the strain on our mother earth? Have a look at all the benefits of decreasing meat in your diet here. And most importantly, plants are delicious.