The Scottish Government has recently published the Climate change adaptation programme: progress report for 2023. This blog reports on the expected impacts of climate change in Scotland and links to the recent posts on climate change targets, terminology, and net zero.
Predicted changes to the Scottish climate
It is important to note that climate change is already happening and that due to ongoing increases in global emissions, further, greater changes are inevitable. For example, the ten warmest years on record have all occurred since 1997. Recent research suggested that only around 60% of people recognise that Scotland is already feeling the effects of climate change.
Predicting future climate impacts is complicated by the uncertainty in future global emissions (although climate model projections have been shown to closely match eventual observations). The image below shows the range of potential future temperature changes under different emission scenarios.
Source: CCC, Independent Assessment of UK Climate Risk (June 2021)
Determining how best to adapt to climate change, or what measures should be prioritised, is made challenging by the uncertainty around the future impacts and thus the benefits from adaptation. It can be difficult to measure the impacts of adaptations as benefits typically entail the avoidance of impacts. Also, the level of future benefits will in part be determined by the global climate mitigation actions; with greater mitigation efforts effectively lessening the benefit from adaptation investments. Some adaptation measures such as tree planting benefit from producing value in terms of emission reductions and climate adaption, like reducing flood risk and providing shade.
Adaptation Scotland – a body funded by Scottish Government to advise on climate change adaptation – have summarised the climate impact projections for Scotland with low and high emission scenarios. The low scenario assumes rapid reduction in GHGs globally with the associated impacts thought to be the minimum that is likely to occur. The current global emissions trajectory is thought to leave Scotland closer to a medium-high scenario. It should be noted that the Climate Change Committee (CCC) have stated that one of the key weaknesses of Scottish climate adaptation planning currently, is that the relevant plans do not consider multiple future global warming scenarios.
In Scotland, some of the headline predictions for climate change are as follows (as reported by the CCC and other sources):
- Temperatures: all seasons will be warmer, there will be less frost and snow. In a medium emission scenario, the annual chance of a heatwave like that seen in 2018 will be about 50/50 by 2050 (in the recent past it was <10%).
- Rainfall: There will be wetter winters and drier summers with the increase in rainfall expected to be larger in the West than in the East. Also, importantly, extreme downpours will be more common, with recent Met Office research finding these could be ten times more likely in North West Scotland by 2080 than they are today (compared to three times more likely in the South of England).
- Extreme weather events: There are expected to be more extreme weather events (including heat waves and downpours). While there will be less rain in summer overall, rainfall intensity could, for example, as much as double in Eastern Scotland (in a high emission scenario).
- Sea level rise: in Edinburgh, sea level is projected to rise by between approximately 12 and 18cm by 2050 (relative to a 1981-2000 baseline) and by approximately 23 to 54cm by 2080 (depending on global emission scenarios). This would lead to an increase in likelihood of flooding of coastal communities. These rates of sea-level rise are lower than for other more southerly UK locations, due to the effects of land rebound from the last ice age being larger towards the north of the UK. As sea level rise may be a very long process, there are projections to 2300 of 0.9-2.6m in a medium-low emissions scenario and 1.7-4.5m in a high scenario.
Impacts of climate change to life in Scotland
Some of the possible impacts from these meteorological changes in Scotland are outlined below:
- Flooding: although flooding will be more of a risk in urban areas, in a world with 2oC of warming the amount of high quality agricultural land at risk from fluvial (river) flooding will increase by 26% by 2050. Increased heavy rainfall events will also increase sewer overflows events.
- Infrastructure: the amount of the railway network that is exposed to significant flooding could increase by over 60% by 2100 under a high-end global warming scenario. Although storms such as Arwen in 2021 can cause major infrastructure disruption, there is currently ‘no clear evidence for increased storminess’ in Scotland.
- Agriculture: while warmer summers and milder winters may increase agricultural productivity (longer growing seasons, less frost damage), extreme weather events and the spread of pests and diseases will limit potential improvements. The Farm Advisory Service states that the positive changes will be ‘largely outweighed by the negative impacts’.
- Overheating: the risk from overheating in Scottish homes is dependent on the level of warming; almost none of the Scottish housing stock was considered to be at risk of overheating with 2oC of warming, but all was at risk under 4oC (see Figure 26 in CCC report). Heat related deaths in Scotland are estimated to be between 70-285 in 2050, in comparison there were 35 per year during the 2000s. Cold has historically been a greater threat to life in Scotland with around 4,000 excess winter deaths in 2020-21. This figure has been falling over time and climate change impacts will act to bring it down further.
There may be benefits (such as lower cold related deaths) or opportunities (the Climate Change Risk Assessment for Scotland highlight eight categories of opportunity) from climate change. The most common perceived opportunities from climate change in Scotland are that of a more active outdoor lifestyle and exercise, and increased tourism.
Small changes in average annual temperature will affect cultural and commercial activities across the country. To improve the salience of climate change (make it more relatable), below are some of the predicted impacts to some of the produce and pastimes present in Scotland.
- Atlantic salmon: while the number of Atlantic salmon returning to Scotland has been in decline for some time (40% fall in 40 years), warmer temperatures will exacerbate stresses, with about 70% of rivers experiencing temperatures that cause stress to salmon during the 2018 heatwave. Tree-planting along riverbanks is mooted as a potential solution to heat stress. Rising ocean temperatures will also affect Atlantic salmon via reduced prey availability.
- Whisky: during the 2018 heatwave malt barley supply was affected by drought, low flows and higher temperatures affected fermentation, and production at some distilleries was halted for weeks.
- Scottish ski slopes: although good conditions have been reported on Scottish mountains last winter, longer term, climate change is anticipated to greatly impact the Scottish ski industry. In the Cairngorms, snow cover is expected to continue within the current range of variation in the near term but with a substantial decline from the 2040s. At the most common elevation for ski activity, a reduction by more than a half of the current number of days with snow cover has been modelled for 2080.
- White Christmas: there has already been a 31% decline in the number of snowy December days in the North of Scotland (difference between 1970-2010 and 2011-21).
Finally, although this blog has considered the impacts in Scotland, the global impacts will be as important (if not more) to life in Scotland as those that happen here. For example, the UK imports about half of the food that it consumes with about 20% of UK-consumed fresh fruit and vegetables thought to come from countries at risk of climate breakdown. There may also be as many as 1 billion climate or environmental migrants by 2050.
Niall Kerr, Senior Researcher, Climate Change and Net Zero