Climate change and Scotland: recent trends and impacts

This paper reviews the key evidence for global climate change and outlines the trends of climate change in Scotland, the potential impacts and the implications for policy makers. Human activity is causing a rise in atmospheric CO2 concentrations and there is little doubt that this is contributing to global warming. There is greater uncertainty about how this global trend will play out at a regional scale and also how close we are to climatic tipping points. Instrumental records document the overall trends and variability in Scotland's climate since 1914. These show that since the 1960s, Scotland's average climate has proved to be wetter (especially in the west) and warmer. This trend is expected to continue throughout the 21st Century with, on average, hotter and drier summers and milder and wetter winters. However, extreme events will continue to affect Scotland, as they have always done, and the severity and frequency of these events may increase. Sea levels will continue to rise modestly, especially in the Outer Hebrides and the Northern Isles. Some of the uncertainty in climatic predictions is captured in the probabilistic outputs of Defra's UK Climate Projections 2009 programme. An initial attempt to assess the likely impacts of climate change is provided in Defra's 2012 Climate Change Risk Assessment, which includes a report specific to Scotland. Whilst most of the risks involve negative impacts, with increased flooding and loss of biodiversity being especially adverse, there are also positive impacts with associated opportunities, especially in terms of increased agricultural production and larger numbers of tourists. The report on Scotland will allow different groups of policy makers to refine the risks associated with specific activities. But given the fragile nature of many of the metrics underpinning the report, caution should be exercised in using it to frame climate adaptation strategies.