Greenhouse gases (GHG) trap heat in the atmosphere causing a greenhouse effect, thus global warming. There are five primary GHG in the atmosphere including water vapour and ozone. The other three – carbon dioxide (CO2), methane and nitrous oxide – are produced in large amounts by human activities.
It is thought that of all anthropogenic (human produced) greenhouse gases, 72% is in the form of CO2, 8% methane and 13% nitrous oxide (1). Both methane and nitrous oxide are much more powerful than carbon dioxide as greenhouse gases. Methane has 23 times the global warming effect of CO2, in other words, it traps 23 times as much heat as CO2 in the atmosphere, and nitrous oxide is 310 times more powerful as a GHG than carbon dioxide or traps 310 times as much heat as CO2 in the atmosphere. Approximately 40% of all methane produced by human activities is from livestock and their flatulences and manure, to the point where atmospheric emissions have risen 145% in the last 15 years. The livestock industry also generates 65% of all human related nitrous oxide (2).
Since 1850, the use of coal, gas and oil (fossil fuels) has increased as the dominant source for global energy use. This has led to a dramatic growth in CO2 emissions. Agriculture, specially animal agriculture, has led to increase production and emissions of methane and nitrous oxide gases, in addition to increase CO2 emissions by burning fossil fuels and deforestation. Together, energy and agriculture are the largest contributing sectors to anthropogenic GHG, 61% and 37% respectively, even though many researchers believe the ratio may be on order of 47% and 51% (3). Although there are other naturally emitting sources of greenhouse gases found on earth, what we produce by burning fossil fuels and rising animals to eat is what causes climate changes (4).
According to the 2006 United Nations report, livestock accounts for 9% of all CO2, 37% of all methane, 65% of nitrous oxide and two-thirds of all ammonia emissions, which cause acid rain and acidification of our ecosystem. This measured in CO2 equivalent constitutes nearly 20% of all anthropogenic greenhouse gas emissions (5), although many researchers now believe that livestock’s contribution is much higher than this (3). And within the agricultural sector, livestock constitutes with 80% of all GHG emissions (6). Global transportation, on the other hand, accounts for 13% of all GHG emissions. In other words, what we currently decide to eat everyday produces more global warming that all cars, planes, trucks and buses in the world combined (7).
The Intergovernmental Panel on Climate Change (IPCC), considered the leading international body for the assessment on climate change, in their fourth assessment report (AR4) concluded that; “most of the observed increase in the global average temperatures since mid 20th century is very likely due to the observed increase in anthropogenic greenhouse gas concentrations”.
A special report by the IPCC in June 2012, in a calculated and conservative fashion, expressed that although it’s difficult to attribute single extreme events such as tropical cyclones to anthropogenic climate change, there is strong evidence of other effects on a global scale:
- Warming of extreme daily minimum and maximum temperatures
- Intensification of extreme precipitation
- Increasing sea levels and coastal high waters
In other words, there will be, perhaps, more devastating weather extremes than what we have already experienced in store for the world, as greenhouse gases increase (8).
Nevertheless we can make a huge impact reducing greenhouse gas emissions, therefore global warming, by adopting a Whole Foods Plant Based Diet, which at the same time will provide us with great health benefits and will contribute to animal welfare.