Climate change is currently one of the biggest threats to our environment. Temperatures are projected to rise by 0.2⁰C per decade over the coming years, with huge implications for our planet’s climate and weather systems, and dangerous consequences for society. We have now gone too far to stop this warming altogether, but we can try to limit it. There is general agreement that keeping this temperature rise to no more than 2⁰C during this century will keep climate change within manageable bounds. However, a 2⁰C temperature rise is still very significant: a drop in global temperatures of only 1 – 2⁰C was enough to cause The Little Ice Age!
The United Nations Environment Programme (UNEP) Emissions Gap Report is an annual report that provides information to governments and communities on progress that has been made to tackle climate change. In order to remain within the 2⁰C temperature rise, the world needs to limit its total annual emissions to 44 billion tonnes of carbon dioxide by 2020. However, the 2013 UNEP report, published on the 5 November, predicts that we will still be emitting 8 – 12 billion tonnes over this required level by 2020. This difference between target emissions and actual emissions is called the ‘emissions gap’. The report lists measures that could help cut this gap, such as using energy more efficiently and increasing our use of renewable energy. Significantly, up to 4 billion tonnes of emissions could be cut simply by changing agricultural practices.
Agriculture is already high on the political agenda. The global population, currently at seven billion, is predicted to reach nine billion by 2050, and ensuring a secure food supply for all those extra people is not going to be easy. We need to re-think our unsustainable, resource-intensive farming practices which are currently damaging soils, the atmosphere and water supplies. Thankfully, help is at hand. Changes suggested by the UNEP report to cut emissions from agriculture will also help us make steps towards more sustainable farming.
Emissions from farming currently account for 10% of the global total. It is also the biggest source of nitrous oxide, a potent greenhouse gas that is released from fertilisers and the breakdown of livestock manure. However, we can reduce nitrous oxide emissions simply by using fertiliser more efficiently, by using less nitrogen-based fertilizers, and by introducing better manure-management practices.
Another option to reduce emissions is conservation tillage. Usually once a crop is harvested, any waste left in the field is removed. However, when conservation tillage is practiced, residue from the previous year’s crop is left on the fields before and after planting the next crop. This can reduce emissions caused by soil disturbance and use of farm machinery, whilst simultaneously replenishing soils with much-needed nutrients to increase fertility.
Introducing sustainable agricultural practices will have far-reaching environmental benefits, including improved soil and water quality, improved habitats for wildlife, and importantly, a reduction of the emissions gap. It is really important that world leaders take action on the UNEP report, particularly where the action that can be taken is so clear. We are treading a fine line between manageable and catastrophic climate change, and if we don’t start cutting emissions soon, it could be too late.