Farming and food

Carbon and nitrous oxide emissions from farming and the food system come from a range of sources: from the chemicals used to treat crops, from energy used to power machines, vehicles, and buildings, and from changes in land use to grow crops or graze animals.

After carbon dioxide, methane is the biggest contributor to climate change and now contributes to around a quarter of all warming. It is less long-lived in the atmosphere but has a warming effect around 30 times stronger than carbon dioxide over a 100-year timeframe. The majority of global methane comes from agriculture, from livestock.

While contributing significantly to climate change, food production and food supply chains are also at increasing risk from its most damaging impacts, with farmers deemed as one of the most vulnerable groups to climate change.

New research suggests that by 2050 harvests of staple crops in eight countries could fall by 80% due to climate change, forcing farmers to switch to different types of crop.

In the UK, extreme and intense weather patterns are affecting harvests of certain crops. For example this year heavy rain followed by intense heat has affected the harvest of fruit, potatoes, and some cereal crops.

For many years emissions from farming have not received the focus of other sectors. In the UK emissions from farming processes are 10% of all emissions. In addition, the UK countryside, most of which is farmed, is also releasing greenhouse gases as a result of degradation of soils, particularly peatlands. The UK’s land is now an overall emitter of greenhouse gases when it should be a long-term absorber and store of carbon.

Agriculture was one element of the UK Government’s new Net Zero Strategy, which said that it will aim for 80% of farmers to be taking some form of low-carbon measures on their farm by 2035. However, the Climate Change Committee has pointed out that there is a lack of detail for how emissions from this sector will be cut compared to others in the economy.

The majority of countries have now submitted 2030 targets for cutting emissions. But most of these targets do not sufficiently address emissions from agriculture.

The UK is currently undergoing a transition in its farming system, with many of these challenges and questions spurring change. In England, the Government has introduced a new Agriculture Act alongside new policies that together aim to pay and reward farmers in return for their work to benefit the environment.

Many farmers are beginning to take action themselves: from those testing net zero approaches to those restoring carbon-rich habitats on their farms.

There are many ways that farming can reduce its emissions, but there are three different types of greenhouse gas that farming is responsible for (carbon dioxide, methane and nitrogen oxide), making it more complex to address through any single policy approach.

• Many farms are installing solar panels, onshore wind turbines and replacing vehicles with electric ones to help to cut carbon dioxide. Some farmers are reducing or cutting out entirely their use of some chemicals like fertilisers, which release nitrogen dioxide. Instead they are growing plants that are able to absorb nitrogen from the atmosphere and add it to the soil, to increase nutrients in a cost-effective as well as climate friendly process.
• Livestock are perhaps one of the most complex and contested areas of tackling emissions in farming. One way to do so involves managing the diet that animals such as cows are fed on to make them produce less methane. Others say that cows should be fed on grass that can absorb carbon and cancel out the animals’ methane emissions, While some say that the numbers of animals should be reduced, which can also improve farmers’ profit margins.

• Restoring nature on farms, such as hedgerows, can help to store carbon. A single hectare of hedgerow can absorb 131 tonnes of carbon every year.
• Emissions also come from the wider food system: the transport, storage, and chilling of food once it has left the farm, as well as the food which is thrown away (around a third of all food).
• The UK imports around half its food. In addition to the emissions released by transporting this food, some of it has been linked with deforestation overseas, for example in recent years the UK has bought £1 billion of beef from three major meat companies who are thought to be responsible for up to 50,000 hectares of deforestation per year.