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Climate change and extreme weather events, establishing a methodology for estimating economic impacts on agriculture - SCF0101

Extreme events are unusual, severe or unseasonal changes in weather patterns that can occur on time scales as short as hours or last for months and include droughts, heat waves, floods and storms. These can present a threat to farmers and growers and given their inherent uncertainty and unpredictability. This research will develop a methodology to assess the costs and impacts of extreme weather events to inform policy decisions on adaptation in Agriculture. The work will be delivered by a team from ADAS and Leeds University, bringing together expertise in climate modeling and impacts and crops, livestock and horticulture sector knowledge.

The first stage is to review the literature on past experience of extreme weather events in England to capture the evidence on occurrence and impact, including economic impact where available. This will be presented on a timeline from 1950 to 2012 to highlight clustering of events by type (flood, drought, and storm), severity, frequency and location. This will be considered along with modeling work on future climate change to inform the profile of events along the timeline from 2013 to 2050.

This analysis provides the context for developing a number of possible scenarios for future occurrence and impact of extreme weather events. These scenarios will be defined in terms of the type of event and the scale and severity of the events, giving a total of 6 extreme weather event scenarios which can be characterised in meteorological terms.

We will then develop a method to estimate the economic costs of extreme weather events on agriculture, based around the 6 scenarios described in stage 2, but able to provide a basis for Defra to consider a wide range of possibilities. This will involve a number of tasks to quantify the area of land affected, estimate the impact on crop or livestock production and apply a price element to give a financial estimate of production lost. The method will also account for additional costs associated with the extreme event, such as remediation of land or preventative measures such as investment in irrigation storage. The approach will also allow for secondary or indirect impacts, for example on subsequent crops or where crop losses affect feed supplies for the livestock sector. The analysis will also account for two levels of preparedness for extreme weather business as usual and prepared to illustrate the cost effectiveness of adaptation measures.

We will also provide a discussive section on the significance of farmer attitudes and responses to extreme weather events and consider the applicability of thresholds or ‘tipping points’ for action.
This will be informed by the analysis but also by the wider literature and experience of farmer behaviour. The methodology for assessing economic impacts relies on a robust analysis of climate scenarios and a comprehensive understanding of resulting impacts on agriculture. The output of this study will provide Defra with a reliable and practicable basis for anticipating the impacts of extreme events and targeting adaptation actions.
The overall aim of this study is to research the evidence of past extreme weather events and their impacts along
with forecast events to 2050 and to establish a methodology for estimating economic impacts on the farming
sector, taking account of attitudes and behaviours in relation to mitigation.
Specific objectives:
1. Refine and agree the scope and approach for the research with Defra along with protocols for
communication, reporting etc. (Month 1)
2. Undertake a Rapid Evidence Assessment (REA) of literature on observed extreme weather events in
England and more widely (where this impacts on English farmers) and socio-economic impacts. This will
include analysis by event frequency and severity, location, farm type, farmer type and preparedness.
(Month 1)
3. Develop scenarios for extreme weather events based on the type of event and mode of impact, which can
be used to test socio-economic impacts. ((Month 2)
4. Report the REA and proposals for scenarios in an Interim Report. (Month 2)
5. Develop a methodology to capture economic impacts which covers all key sectors and provides analysis
of primary impacts at both farm and industry level, and allows for second-level impacts e.g. response to
market changes. (Month 3)
6. Provide a Final Report, including opportunity for Defra to comment on a draft. (Month 3)
7. Present the study and its findings to Defra and up to 2 presentations to a wider audience. (Month 4)
Scope: This project covers England only.
Project Documents
• EVID4 - Final project report : evid4 Extreme Weather   (249k)
• FRP - Final Report : Extreme Weather Final Report June2013   (1398k)
Time-Scale and Cost
From: 2013

To: 2013

Cost: £33,030
Contractor / Funded Organisations
Climate Change              
Economic Methodologies