To answer some questions about the facts presented in our video "Global warming: what can you do?", below are explanations with references to the evidence for these and other facts.
Global warming and animal agriculture
"Animal farming emits 50% of Australia's greenhouse gases"
The amount of Australia's greenhouse gases emitted by animal agriculture is usually reported at about 27%. This is because these figures use a 100 year time scale and ignore the warming impact of short lived greenhouse gases. The use of a 100 year time scale is a convention that may have been a valid decision decades ago when the urgency of global warming was not as apparent but now there is a much better case for using a 20 year time frame, being more in line with the possibility of reaching various climatic tipping points. Also, it is now realised that short lived greenhouse gases have a very significant impact and the warming effect of these emissions should not be ignored.
If we include short lived gases and use a 20 year time scale we find that animal agriculture emits 50% of Australia's greenhouse gases. See more in the first section of Impact of a vegan agricultural system on the environment.
For a full analysis see the paper "Neglected Transformational Responses: Implications of Excluding Short Lived Emissions and Near Term Projections in Greenhouse Gas Accounting" and the BZE Zero Carbon Australia Land Use report (p68-69).
The figure of 50% is also true at the global level. See the paper Livestock and Climate Change from the Worldwatch Institute.
"Animal agriculture takes up 56% of the Australian landmass"
Since European settlement, the Australian continent has been extensively modified by animal agriculture, with livestock (mainly cattle, sheep and dairy) grazing native or modified pastures on 56% of the continent. About 3.5% of land is used to grow plant foods for humans. See Land Use in Australia - At a Glance published by the Australian Department of Agriculture.
See more in the first section of Impact of a vegan agricultural system on land use.