The world’s climate has definitely undergone significant changes over the past 50 years. The result is that my colleagues and I no longer discuss climate change in the future tense, but in the past tense.
When the issue of climate change really hit home about 15 years ago, researchers focused on potential future scenarios of the impact of climate change on global agriculture and other issues. Nowadays, the same researchers, including myself, spend more time analysing which aspects of the climate have already changed and what the impact of these changes has been on global agriculture. This is quite sobering.
The 3 P’s of climate change
Given the complexity of communicating climate change to audiences with differing views or biases, as well as diverse political affiliations, my colleagues and I at the Primary Industries Climate Challenges Centre (PICCC) had to come up with a way to look at climate change more broadly. We eventually came up with what we’ve termed the ‘3 P’s of Climate Change’.
The first of these P’s are the physical aspects of climate change, which include temperature, rainfall, humidity, evapotranspiration, elevated atmospheric carbon dioxide (CO2) levels, and their effects on plant growth and extreme weather events.
The second P refers to the policy implications of climate change. There are still many climate change sceptics, as well as people who believe that climate change is real, but is not caused by human activities. Irrespective of their views on the physical impact of climate change, there will be political and policy implications that will affect agriculture in the various countries and regions of the world.
Examples of this include the Paris COP21 agreement signed in December 2015, greenhouse gas emissions trading, and carbon pricing.
The third P refers to people. There is a large social component to climate change. For example, adapting to climate change requires personal change from farmers.
Many assessments have been made of the potential impact of climate change on global agriculture in the coming decades. In his book, Global Warming and Agriculture, William R Cline predicts that the southern hemisphere will be far worse affected in terms of food production than the northern hemisphere.
Much potential agricultural land is expected to become arable in the northern hemisphere as the effects of climate change progress. Investors are already buying up land in Canada that was previously permafrost because they see the potential for agricultural production on this land.
The United Nations Environment Programme (UNEP) has also previously stated that 25% of the world’s food production may be lost to environmental breakdown – largely attributed to climate change – by 2050. This is quite a severe assessment, given that we know the world population will need 70% more food by 2050.
It is important to note that, after Australia, South Africa has the second- most variable rainfall and climate in the world, even before the effects of climate change are taken into account.
In Australia, we are already recording the southward movement of our country’s climatic zones, which traditionally consisted of monsoon conditions across the north, a tropical climate in the central areas, and winter rainfall conditions in the south. This is having a dramatic effect on Australian agriculture, with farmers having to change their seasonal production planning, or even having to move elsewhere or stop farming entirely.
It is a fact that the earth’s average annual temperature has increased by 0,9°C since 1910. It is also a fact that 2015 was the 39th consecutive year with an above-average annual global temperature. How many consecutive years of these above-average temperatures do people actually need to experience before they begin to acknowledge that change is taking place?
Climate change and trade
While there were 177 signatory countries to the Paris COP21 agreement, I have noticed that greenhouse gas emissions trading and carbon pricing are actually being used as trade barriers between countries. This will affect international agriculture.
For example, among the targets set by the European Union’s (EU) Renewable Energy Directive is 60% fewer greenhouse gas emissions from biodiesel products by 2018. Effective research is essential to achieve this target and others like it.
Australia has already developed low- emission and non-genetically modified canola production systems that meet the
EU’s requirement on biodiesel products and therefore have priority access to EU canola markets. The agricultural sectors of many other countries cannot meet these and other increasingly stringent requirements and may be locked out of this lucrative market.
While the Paris COP21 agreement does not specifically refer to agriculture, it focuses strongly on global food security. Article 2a of the agreement requires countries to work towards limiting average annual temperature increases since 1910 to well below 2°C. It also encourages efforts to limit these temperature increases to 1,5°C above pre-industrial age levels.
However, climate change researchers know that greenhouse gas emissions already present in our atmosphere will actually take us beyond the 1,5°C temperature increase limit. This means that we somehow have to sequester greenhouse gases from the atmosphere, or come up with quick solutions to significantly decrease current emissions. What is also concerning is that the target set for greenhouse gas emissions in the Paris COP21 agreement will still leave the world with a 4,5°C global temperature increase.
One of the issues that will have to be addressed is that the global industrial sector has, for many years, looked at the world’s agricultural land-based sector to offset its greenhouse gas emissions. This is done, for example, by planting trees to offset emissions from power stations.
My analysis of Australian conditions would suggest that the world’s agricultural sector will need its own land offsets, and should not hand over its offsets to the industrial sector.
One of agriculture’s climate change aims needs to be the reduction of livestock methane emissions. Methane lasts for
only 12 years in the atmosphere, but during that time it warms the planet 86 times more than CO2 emissions.
Policymakers have quickly latched onto this aspect of climate change: agriculture will either have to sequester atmospheric carbon in trees and soil, or address short-lived climate pollutants such as methane. Reducing livestock methane emissions is considered a preferable quick-fix solution by policymakers.
Of the signatory countries to the Paris COP21 agreement, 80% agreed to include land sector climate change mitigation targets, and 54% specifically wanted to focus on reducing livestock methane emissions. This signals that agricultural production adaptation, particularly livestock production, will become an imperative.
There are various options available to reduce livestock methane emissions, including improving beef herd production efficiencies, feeding beef cattle nitrate, feeding dairy cattle dietary oils, reducing methane production in dairy cattle manure, using fertilisers more efficiently in oil seed production, and sequestering soil carbon in grazing systems.
Financially viable solutions
The key is to make the implementation of these options financially viable for livestock farmers, so that they can generate carbon credits to trade for additional income. At present, though, studies in Australia have found that increasing livestock productivity while maintaining existing methane emissions levels is far more profitable than focusing on reducing these levels.
Therefore, it is vital that research continues to focus on finding profitable and productive options to reduce livestock methane emissions while still improving the climate change resilience of farming systems.
Research will need to focus on finding ways to intensify agricultural production in regions that are more water-secure,
but diversify production in regions where the climate is more variable. – Lloyd Phillips