CLIMATE CHANGE IN AGRICULTURE
Vincenzo Campione1. Agriculture and climate change
Agriculture is essential for humankind – it provides the food we eat, serves as the livelihood of millions of people worldwide, and manages a large share of the landscape. In doing so, however, greenhouse gases (GHG) are released, making agriculture also a source of emissions which contribute to climate change. Since agriculture depends on natural resources and the climate to provide a suitable environment for crops to grow, climate change threatens to cause major disruptions for agriculture in the future. Adaptation or building resilience in agriculture must therefore be prioritised alongside efforts to reduce emissions from the sector and maintain food production. Balancing these competing interests presents a significant policy challenge.
1.1 Greenhouse gas emissions from agriculture
Various types of GHGs are released during agricultural production. Of the six official GHGs that are accounted for under the international climate change treaty, the United Nations Framework Convention on Climate Change, only methane and nitrous oxide are accounted for as agriculture emissions. These gases are emitted during activities such as livestock production and spreading of manure or chemical fertilisers on fields to nourish the crops.
Additionally, emissions from managing agricultural soils, land use change, and forestry activities are accounted for separately under the Land use, land use change and forestry sector of the. Agriculture is a source of carbon dioxide, N2O, and CH4 emissions, resulting from management activities, such as the ploughing of soil and draining of wetlands to use for agriculture. Forestry also results in emissions when wood products are harvested.
Agriculture and forestry are unique sectors, however, because they act not only as sources of emissions but also as sinks, with the ability to remove atmospheric carbon by soaking it up and storing it above or below ground in the plants and soil. This natural process allows these land-based sectors to mitigate global emissions to a certain extent, though processes such as deforestation of tropical rainforests and large-scale grassland conversion reduce their potential. Figure 1 below demonstrates the various ways in which agriculture and forestry act as sources and sinks for GHGs.
Agriculture and forestry act as a GHG source and sink
Plants remove atmospheric carbon and store it above and below ground, while agricultural practices and deforestation contribute to varying levels of GHG emissions.
Agriculture accounts for approximately 10% of the EU’s total GHG emissions. In comparison to other sectors, transportation comprises nearly 20% and electricity and heat generation in the EU accounts for over 25% of the total GHG emissions. However, agriculture also contains "hidden emissions" that are attributed to other sectors, e.g., CO2 emissions from fossil fuel and electricity used for machinery, drying crops, and the manufacture of fertilisers / pesticides are accounted for by the energy sector.
1.2 Agriculture also needs to adapt to climate change
Agriculture is a nature-based, climate-dependent sector which will experience multiple impacts from climate change. Some of the key anticipated impacts of climate change for agriculture will include decreased annual rainfall, increased frequency of droughts and flooding, and increased risk of pests and diseases. Thus, it is important that agriculture builds the capacity to adapt to climate change in order to reduce negative impacts.
Various opportunities exist for mitigation and adaptation in agriculture. Many agricultural practices which are beneficial for mitigation also have positive contributions for water, soil and biodiversity protection, as well as for adaptation. There are various synergies which exist between adaptation and mitigation activities in agriculture. For example, including grasses in crop rotations decreases emissions while providing year-round cover of the ground, thus reducing soil erosion and increasing the retention of water in the soils. Many actions exist that can reduce the impact the sector on climate change while maintaining productivity levels to meet food demand.