Economics of Climate Resilience: Agriculture
Executive summary
How exposed is UK agriculture to climate change?
Key climate risks facing the sector are changes in average climate conditions, changes to the inherent variability of weather, and the increased frequency and severity of extreme weather events. Changes to extreme events, such as floods and drought are a potentially greater threat to agriculture than changing average conditions (Knox et al., 2012).
Impacts of climate change on projected yields are subject to uncertainty. Based on projections from the International Food Policy Research Institute (IFPRI), across a range of climate change and socio-economic scenarios, yields in 20501 could be lower by 0.03-0.8 t/ha for wheat, 0.4 to 5.7 t/ha for sugar beet and yields could increase by 1.3 t/ha or decrease by 2.6 t/ha for potatoes, than under the current climate in that year(based on Nelson et al., 2010).
Increasing CO2 concentrations (not reflected in these projections) could however increase yields by perhaps 15% higher than without the climate change effect (assuming adequate water and nutrients), according to field research (Semenov and Shewry, 2011). However, the impacts of pests and diseases or other extreme events, such as drought, (none of which is reflected in the projections), could all act significantly in the opposite direction.
In response to these challenges, this report addresses the question set by Defra:
“Given projected climate change and current or likely adaptation, what is the case for further intervention in relation to climate change adaptation for agricultural productivity (crop yields) and production?”
Defra has requested that this work focuses on: wheat yield; sugar beet yield; potato yield, grassland yield (as a key input for livestock productivity); and, that additional commentary is provided on wider horticulture, pigs and poultry.