Sustainability West Midlands The Potential Impacts of Climate Change in the West Midlands Technical Report December 2003 Entec UK Limited The ‘Selly Oak Twister’ Birmingham July 5th 1999 Report for Sustainability West Sustainability West Midlands c/o West Midlands Local Government Midlands Association 4th Floor Lombard House 145 Great Charles Street The Potential Impacts Queensway Birmingham of Climate Change in B3 3LS the West Midlands Main Contributors Michael Anderson Technical Report Sabrina Dann Chris Hughes December 2003 Jim Kersey Lee Chapman John Kings Entec UK Limited John Thornes Alistair Hunt Tim Taylor Issued by ………………………………………………………… Chris Hughes Approved by ………………………………………………………… Jim Kersey Entec UK Limited Gables House Kenilworth Road Leamington Spa Warwickshire CV32 6JX England Tel: +44 (0) 1926 439000 Fax: +44 (0) 1926 439010 Certificate No. EMS 69090 Certificate No. FS 13881 h:\projects\hm-250\09716 wmids cl ch\reports\technical report.doc In accordance with an environmentally responsible approach, this document is printed on recycled paper produced from 100% post-consumer waste, or on ECF (elemental chlorine free) paper i Foreword Sustainability West Midlands (SWM) is leading the preparation of the West Midlands response to adapting to climate change on behalf of regional stakeholders. As a first step, SWM commissioned Entec to conduct a regional Climate Change Impact Study which sets out the overall picture of issues, challenges and priorities in the West Midlands for the first time. This Summary Report reflects the main findings of a more detailed Technical Report. The Impact Study captures a key moment in time for the region and is drawn from a wealth of more detailed and specific research studies. The study has also engaged with specialist climate change interests around the United Kingdom as well as regional organisations, agencies, partnerships and networks, individually and collectively, to develop regional knowledge and produce these findings and recommendations. This study provides a good foundation for the next stage of the process – the development of ways of raising awareness and planning responses within the West Midlands. Discussions are already underway with the West Midlands Regional Concordat partners (comprising eleven regional decision making bodies including SWM) and a range of sector representatives and partners who are developing responses to the climate change challenge. These policy setters and decision makers will declare commitments to the need to give greater prominence to climate change in their own policies, programmes and projects delivering their core business. The climate change study and outcomes are feeding into the current Review of the West Midlands Regional Sustainable Development Framework and other key regional strategies such as Regional Economic Strategy, Regional Planning Guidance, Regional Housing Strategy, Regional Energy Strategy, West Midlands European Framework. The clear message emerging out of this first stage is that no one person, organisation or community of interest can shape and deliver commitments to climate change alone. The Region is collectively determined to work together to make change happen for the better and ensure that the issues raised are addressed as part of its plans for a more sustainable future. Bernard Doyle Chair, Sustainability West Midlands January 200 ii iii Executive Summary This scoping study examines the evidence for climate change in the West Midlands and outlines possible future climates. From this, the study considers the possible impacts of these changes on a range of issues, building on a pre-scoping study for the region completed in 2001. The report also puts forward a number of possible adaptation options. The study aims to encourage policy responses to climate change that are appropriate to the West Midlands as it has included significant consultation with individuals and organisations across the region. It is also intended to raise awareness of the implications of climate change and to encourage an increased understanding of the common issues faced by the entire region in the event of various climate change outcomes. Climate change is happening in the West Midlands The climate of the region changed significantly in the last century. The key changes are given in the following table. Climate indicators Recent trend Air temperature Annual average temperature has risen by +0.6ºC since the 1900s Several of the warmest years on record have occurred since 1989 Growing season has increased by 30 days since the 1900s Nocturnal urban heat island intensifying Rainfall Decreasing summer rainfall since the 1880s Increasing winter rainfall over last 150-200 years More winter rain days and longer wet-spells since the 1960s Heavy storms have contributed more to winter rainfall totals since the 1960s Snowfall Fewer snowfall events and smaller snowfalls since the 1960s Gales Record wind speeds in 1987 and 1990 No long-term trend but cluster of severe gales in the 1990s So climate change is happening but what about the future? The future climate of the West Midlands Models of the future climate suggest that the region’s climate could change in the following ways: • The average annual mean temperature in Birmingham between 1961 and 1990 was 9.4oC. This is expected to increase by between 0.5oC and 1.5oC by the 2020s and between 1.0oC and 2.5oC by the 2050s; iv • Most of the warming is expected to take place in summer although winters are also expected to be significantly warmer. Warwickshire and the south east of the region are expected to warm up more than Shropshire and the north west of the region; • The mean annual precipitation is expected to change by less than 10% by the 2050s. However, this hides a dramatic change in seasonal precipitation. Winter precipitation might increase by between 0% and 10% by the 2020s and up to 20% by the 2050s. On the other hand, summer precipitation might decrease by between 0% and 20% by the 2020s and up to 30% by the 2050s; • Cloud cover is expected to decline slightly overall (between 2% and 6% by the 2050s) with a small increase of up to 2% in winter and a larger reduction of up to 10% in summer by the 2050s; • Overall the mean relative humidity (the amount of water vapour in the air in comparison to the maximum saturation) is likely to decline by a small amount in winter (up to -2%) and decline much more in summer (-2% to -4% by the 2020s and -2% to -8% by the 2050s) as the air temperature is expected to increase. This may lead to a reduction in the number of days with fog; • The mean daily wind speed is not expected to change very much over the year (0% to +1%) but winter mean wind speed is expected to increase by up to 4% in the south east of the region by the 2050s. Summer mean wind speed is likely to stay the same (+/- 1%). However, there are low levels of confidence in the modelled wind speeds; and • The potential changes in soil moisture are quite dramatic. Soil moisture is a function of temperature, precipitation, humidity, sunshine and wind speed. Overall in summer the region would be drier and warmer and hence soil moisture could fall by between 5% in the north west of the region and 35% in the south east by the 2050s. In winter however, the increased precipitation could lead to higher soil moisture levels and the increased probability of flooding. As well as the changes in average climate conditions outlined above, the occurrence of extreme climate events is also expected to change. This could be in the daily extremes of temperature or precipitation for example, or in the occurrence of extreme years. The figures in the following table indicate the percentage of years in which various extreme events could occur. For example, a 1995-type summer could occur 20% of the time, one in every 5 years, by the 2050s. Percentage of years in which England and Wales could experience extreme climate events Climate event Difference relative to 2020s 2050s 2080s the 1961-90 average A hot ‘1995-type’ August 3.4ºC warmer 1 20 63 A warm ‘1999-type’ year 1.2ºC warmer 28 73 100 A dry ‘1995-type’ summer 37% drier 10 29 50 A wet ‘1994/95-type’ winter 66% wetter 1 3 7 Source: Hulme et al. (2002) v Climate change impacts and opportunities The pre-scoping report (included as Appendix G) considered fifteen sectors and issues in the West Midlands. However, in order to consider the potential impacts in more detail, this study focuses on five ‘hot issues’ identified at a regional workshop as being of most importance from a climate change perspective. They are as follows: • Water Management; • Agriculture; • Energy; • Land Use and the Built Environment; and • Transport. The potential impacts of climate change on the ‘hot issues’ were identified based on information on the current situation in the West Midlands, and possible future economic and social changes. Assessment of these impacts was developed through consultation with people and organisations across the region. In summary the general potential climate change impacts for the region include the following: • Increased temperatures and different patterns of rainfall could lead to changes in the demand for, and availability of, water. A significant proportion of the region’s water is supplied from reservoirs in Wales, which has a wetter climate. Drier summers could result in lower flows in the region’s rivers, with negative impacts on biodiversity and water quality, and an increase in the demand for water for irrigation, garden watering, industry (especially food and drink) and the public. However, whether these impacts actually occur will depend on the success of implementing an effective regional water strategy and measures to address supply and demand issues; • Increased temperature could change the demand for energy, with a reduction in demand for winter space heating and an increase in the demand for cooling in the summer.