Environmental and Socio-Economic Impacts of Climate Change on the Brue Valley Final Report for Somerset Wildlife Trust and the Brue Valley Living Landscape Project RPA May 2011 Environmental and Socio-Economic Impacts of Climate Change on the Brue Valley Final Report prepared for Somerset Wildlife Trust and the Brue Valley Living Landscape Project by Risk & Policy Analysts Limited, Farthing Green House, 1 Beccles Road, Loddon, Norfolk, NR14 6LT Tel: 01508 528465 Fax: 01508 520758 Email: [email protected] In association with Geckoella environmental consultants pvt ltd Suite 323, 7 Bridge Street, Taunton, TA1 1TD Tel: 0392 762334 Email: [email protected] Environment Systems Ltd 8G Cefn Llan Science Park, Aberystwyth, Ceredigion, SY23 3AH Tel: 01970 626688 Email: [email protected] This report should be cited as: RPA, Geckoella and Environment Systems (2011): Environmental and Socio-Economic Impacts of Climate Change on the Brue Valley, report prepared for the Somerset Wildlife Trust Brue Valley Living Landscape Project, May 2011. RPA REPORT – ASSURED QUALITY Project: Ref/Title J716/Brue Valley Approach: In accordance with the Proposal Report Status: Final Report Report Prepared by: Teresa Fenn, Principal Consultant, RPA Rocio Salado, Senior Consultant, RPA Elizabeth Daly, Consultant, RPA Andy King, Co-director, Geckoella Kate Jeffreys, Co-director, Geckoella Steve Keyworth, Director, Environment Systems Eleanor Goupillon, Environment Systems Report approved for issue by: Meg Postle, Director, RPA Date: 13 May 2011 Executive Summary EXECUTIVE SUMMARY 1. Introduction Climate change is one of the main challenges to be faced by policy makers and local stakeholders in the years to come. This study focuses on assessing how climate change and socio-economic factors may interact to impact land use, habitats and biodiversity in the Brue Valley. The results will feed into the Wildlife Trusts’ ‘Living Landscape’ initiative, The European Interreg IVB NWE WAVE (Water Adaptation is Valuable for Everybody) project and Natural England’s Wetland Vision projects. By turning the Vision into reality, the aim is for partner organisations to make space for water in our countryside, help people and wildlife adapt to a changing climate, protect our heritage and reap the many benefits that wetlands can provide. 2. Objectives The overall objectives of the study are: to provide a scientifically sound assessment of the impacts of climate change on the habitats and land uses in the Brue Valley; to deliver outputs in formats that can be easily understood and interpreted by local stakeholders; to provide a complete record of the study such that the approach is transparent and auditable; and to assess scenarios that take account of the variety of land uses and which identify the full range of potential impacts (economic, environmental and social). 3. Structure of the Study Figure 1: Study Navigation Diagram Figure 1 shows how the different aspects of the study fit together. The study begins with a baseline assessment, which involves the description of the land uses and habitats currently present in the Brue Valley. As part of this initial assessment, all areas are allocated to one of - i - Executive Summary fourteen features, e.g. lakes/ponds, dry grassland of high value for wildlife. Information from UKCP09 is then used to examine how the climate might change, and how these changes could affect the features identified. Four different socio-economic scenarios are subsequently developed. These four generic scenarios are used as the basis for developing detailed socio- economic scenarios for the Brue Valley. These detailed scenarios use the principles outlined in the IPCC Special Report on Emission Scenarios, UKCIP 2001 and the Millennium Ecosystem Assessment to build up projected futures for the Brue Valley. Figure 2 shows the basis for the four scenario types and the ideologies on which they are based. It also shows where the four detailed Brue Valley scenarios plot onto the scenario matrix. Globalisation/ World Markets Global Sustainability Interdependence (homogeneous world) Localisation/ Autonomy (heterogeneous world) (see A5.5) Provincial Enterprise Local Stewardship Individualism/ Community/ Consumerism Conservation (more economic focus) (more environmental focus) Figure 2: Approximate location of the four scenarios developed for the Brue Valley Each scenario makes a series of assumptions with regard to a range of variables including farming methods, commitment to environmental protection, peat extraction, water management, etc. Combining these scenarios with the potential changes in climate enables the development of feature-by-feature storylines. These investigate how the habitats and land-uses might change in response to the different climatic conditions and human influences. Consideration is also given to likely adaptation actions that might be taken under the different socio-economic scenarios. Bringing together the changes at the feature level enables overall changes to the landscape and ecosystem services to be identified. This allows comparisons to be drawn between the scenarios and highlights which features are likely to be more or less vulnerable to climate change. 4. Assessing the Impact of Climate Change Climate change data from UKCP09 are used to look at how the Brue Valley might be affected. This study focuses on the high emissions scenario and takes into account both the 10% and 90% probability levels. This approach is used for two main reasons: use of the high emissions scenario maximises the projected climate change variables so that worst-case changes can be identified; and the 10% and 90% probabilities indicate the possible changes at the two ends of a range of climate projections. For the 10% probability, there is a 90% chance that any impacts will be greater, whilst for the 90% probability, there is a 90% chance that impacts will be - ii - Executive Summary smaller. Using more than one probability also ensures that the advice of the UK Climate Projections Project (UKCPP 2011) is followed. Consideration of both probabilities is particularly important given the differences between them. Under the 10% probability, conditions are anticipated to be hotter but drier, whilst under the 90% probability, conditions are hotter, but wetter. The study resources are therefore targeted towards the assessment of the climatic variables that are likely to have the greatest impacts on the features present in the Brue Valley, namely temperature and precipitation levels. 5. Impacts of Climate Change on Features Table 1 summarises some of the impacts anticipated under the two different climate probabilities, before socio-economic adaptations are taken into account. Positive and negative impacts are denoted by + and - respectively, with each referring to whether an impact is positive or negative for that particular feature, rather than for the overall landscape or environment. Anticipated impacts from the change in freshwater flood risk are shown in Table 2. Note that some features are grouped due to the projected similarity in impacts. Table 1: Features Assessed in the Study Area Impact of Climate Change Habitat Feature (ha) 10% 90% + Possible slight increase in + Reduction in irrigation maize crop requirements for winter + Slightly drier autumn may wheat of 33mm benefit cultivations Cereal crops 381 Cereal crops - 15% increase in autumn - Reduction in yields of rainfall may affect winter wheat crops by cultivations 14% Lowland - Increased temperatures in - Increased temperatures in meadow with spring, summer and 0.5 spring, summer and calcareous autumn could cause stress autumn could cause stress indicators to livestock Dry to livestock - Too much of an increase in Lowland grassland of -/+ Lowering of water table rainfall could result in meadow with 1 high value results in reduced biomass waterlogging stress. acid indicators for wildlife production – implications - Increased temperatures for management, effects Species-rich may enable pests to 56 on community survive (with particular dry grassland composition impacts for livestock) Grass and Dry + Increased rainfall could - Lowering of water table grass clover 0.0004 grassland of increase biomass results in reduced biomass leys low value production Improved for wildlife - Increased temperatures in 2,377 grassland spring, summer and - iii - Executive Summary Table 1: Features Assessed in the Study Area Impact of Climate Change Habitat Feature (ha) 10% 90% autumn could cause stress to livestock - Too much rainfall could result in waterlogging Species-poor 1,680 stress dry grassland - Increased temperatures may enable pests to survive (with particular impacts for livestock) Intensively - Wetter conditions could managed 1 - Possible small reduction in increase growing and orchards yields of around 3% due to harvesting costs Other non- Orchards drier conditions - Higher temperatures could 35 cereal crops and - May be larger impact in affect yield and quality of horticulture terms of crop quality and some crops Other difficulty of achieving - Warmer and wetter arable/horticult 2 uniform quality and size conditions may favour ural some pests and diseases Fence 0.1 - Increased pressure on - Increased run-off from Roads Other 855 water resources possible very high intensity rainfall Settlements Ex-Peat + Peat extraction is 146 working site facilitated by lower water levels - Higher temperature in combination with reduced Peat works precipitation enhance - Wetter conditions make and bare short-term