The University of Manchester Research The future climate of North West England Link to publication record in Manchester Research Explorer Citation for published version (APA): Cavan, G., Carter, J. G., & Kazmierczak, A. (2010). The future climate of North West England. EcoCities project, University of Manchester. Citing this paper Please note that where the full-text provided on Manchester Research Explorer is the Author Accepted Manuscript or Proof version this may differ from the final Published version. If citing, it is advised that you check and use the publisher's definitive version. General rights Copyright and moral rights for the publications made accessible in the Research Explorer are retained by the authors and/or other copyright owners and it is a condition of accessing publications that users recognise and abide by the legal requirements associated with these rights. Takedown policy If you believe that this document breaches copyright please refer to the University of Manchester’s Takedown Procedures [http://man.ac.uk/04Y6Bo] or contact [email protected] providing relevant details, so we can investigate your claim. Download date:08. Oct. 2021 The future climate of North West England Cavan, G. Carter, J. and Kazmierczak, A. 1 Introduction........................................................................................................ 3 1.1 Background to climate change................................................................... 3 1.2 Emissions scenarios .................................................................................. 4 1.3 Probability levels........................................................................................ 6 1.4 Time periods.............................................................................................. 6 2 Climate change projections for North West England.......................................... 7 2.1 Projections of changes in temperature....................................................... 8 2.1.1 Annual mean temperature.................................................................. 8 2.1.2 Winter mean temperature................................................................. 10 2.1.3 Summer mean temperature.............................................................. 10 2.1.4 Summer mean daily maximum (daytime) temperature ..................... 11 2.1.5 Change in temperature of the warmest day of the summer .............. 12 2.1.6 Summer mean daily minimum (night-time) temperature ................... 13 2.1.7 Change in temperature of the warmest night of the summer ............ 14 2.2 Projections of changes in precipitation..................................................... 15 2.2.1 Annual mean precipitation................................................................ 15 2.2.2 Winter mean precipitation................................................................. 16 2.2.3 Wettest day in winter........................................................................ 17 2.2.4 Summer mean precipitation ............................................................. 18 2.2.5 Wettest day in summer..................................................................... 19 2.3 Changes in relative humidity .................................................................... 20 2.3.1 Summer mean relative humidity ....................................................... 20 2.3.2 Winter mean relative humidity .......................................................... 20 2.4 Changes in cloud cover ........................................................................... 21 2.4.1 Summer cloud cover ........................................................................ 21 2.4.2 Winter cloud cover ........................................................................... 22 3 Impacts of climate change ............................................................................... 23 4 The adaptation imperative and EcoCities ........................................................ 24 5 References...................................................................................................... 25 6 Acknowledgements ......................................................................................... 26 This report should be referenced as: Cavan, G. Carter, J. and Kazmierczak, A. (2010).The future climate of North West England. EcoCities, University of Manchester. 2 1 Introduction The UK Climate Projections (UKCP09) provided through the UK Climate Impacts Programme (UKCIP) is the latest and most comprehensive package of information on the potential future climate for the UK. Continuing improvements in modelling and understanding of the climate system allow climate projections to be periodically reviewed and refined. This latest set of projections is an improvement on the last suite of UKCIP02 scenarios as they are downscaled to a 25km grid and provide a probabilistic element. Thus, for the first time, it provides information on the relative degree to which each projected climate outcome is supported by current evidence. Changes in the Gulf Stream are taken into account, as are carbon feedbacks are aerosols. The UKCP09 projections are therefore more complex, but respond to demands from users for this level of detail (Murphy et al., 2009). The UKCP09 website provides a range of readily-available information for the future climate of the North West region. This includes text, graphs and mapped outputs1. This report compiles some of this readily-available information to summarise the key future changes to the North West region. In addition, it includes some customised information that was created in the UKCP09 user interface2. This document summarises climate projections information for the North West region in tables, graphs, maps and descriptions. It provides information for a range of climate variables, time periods, emissions scenarios and probability levels. It begins by providing a brief background to climate change, the emissions scenarios used in UKCP09, an introduction to the probability levels including an explanation of how probability should be interpreted in the climate projections, and a note on time periods. The information on the future climate of the North West region is of potential value for a wide range of stakeholder groups wishing to learn more about this subject. Although the UKCP09 website provides access to some of this information, and offers the potential to obtain more through the user interface, this report brings together a summary of the relevant climate change projections data for North West England in an easily accessible format. 1.1 Background to climate change The Earth’s climate has continually changed throughout history, influenced by natural factors such as volcanic activity, changes in solar output, changes in the Earth’s orbit and oscillations in the climate system such as the North Atlantic Oscillation (NAO) and El Nino Southern Oscillation (ENSO). The difference between these natural cycles and the recent changes in climate we have experienced is the rate that change has 1 UKCP09 pre-prepared maps and graphs for North West England are available at: http://ukclimateprojections.defra.gov.uk/content/view/292/499/ 2 UK Climate Projections User Interface can be accessed at: http://ukclimateprojections- ui.defra.gov.uk/ 3 occurred. Global warming rates have increased to 0.17 ± 0.05°C per decade – likely to exceed any 100-year rate of warming during the past 1000 years (EEA, 2004). These recent changes to the climate cannot be explained by natural causes (Stott et al., 2000; Hulme et al., 2002). In fact, we can now state that it is very likely (>90% probability) that this warming of the observed global average temperature is due to anthropogenic emissions of greenhouse gases (Jenkins et al., 2007). In other words, humans are contributing to warming through emissions of greenhouse gases from burning fossil fuels, causing the climate to change beyond its natural variability. These human-induced emissions include carbon dioxide, one of the main greenhouse gases, the atmospheric concentrations of which have increased by 34% compared with pre- industrial levels, and an accelerated rise has occurred since 1950 (EEA, 2004). Changes to land use and natural systems on a global scale, including the loss of rainforest and changes in agricultural practices, also contributes to the increased emissions of greenhouse gases. Some degree of climate change is now inevitable due to the impact of historical emissions, and the amount of future warming will greatly depend on the future emissions of greenhouse gases (Section 1.2), the extent of land use change, and the associated response of natural systems. 1.2 Emissions scenarios In order to make projections of climate change in the UK over the next century, it is necessary to make some assumptions about future emissions of greenhouse gases (and other pollutants) from human activities (Murphy et al., 2009). The IPCC Special Report on Emissions Scenarios (SRES) (Nakienovi and Swart, 2000) defined different future emissions pathways based on potential storylines for the future. These representations of the future development of emissions are based on a coherent and internally consistent set of assumptions about factors such as demographic changes, socio-economic development and technological change. Six storylines for future emissions were developed, each resulting in different estimates of greenhouse gas emissions and the associated increase in global