Flooding & Drought

Like the rest of the world, extreme changes are expected to happen by 2050 in the Scottish climate and this will bring many unprecedented impacts. Predictions include the water environment across Scotland will be affected and pose health risks to humans and nature, as the water quality may become unsafe. Water accessibility could also be affected by the warming climate and changes in rainfall patterns because there will be increased demand for supply between agriculture, industries, and households, alongside the natural needs of the local environment. Summer droughts are even predicted to become more frequent and severe across Scotland which will make our water supplies less reliable. Droughts will also cause our wetlands to dry out and release carbon, which adds to the number of greenhouse gases emitted into the atmosphere.

At present, these are relevant issues that we have begun to experience across Scotland and the rest of the UK. This summer, the UK has already experienced some extreme spells of hot weather. This led to a red Met Office warning to be issued for prolonged heat, with temperatures reaching up to 40 degrees Celsius. This is unheard of in the UK – temperatures of up to 40 degrees were only predicted in 2050! Clearly the planet is warming at a much faster rate than originally anticipated. Though alongside the warmer and drier summers, Scotland is likely to experience wetter winters due to variable rainfall, heavy downpours, and more frequent storms which will increase the risk of future flooding.

Flood risk and drought across Scotland can bring serious consequences for local properties and infrastructure, as well as long term impacts to our communities, businesses, and local heritage. Flooding has become more of a regular occurrence across Scotland over the last fifteen years – increased rainfall, frequent storms and more rapid snowmelt from the mountains have amplified the quantity, velocity, and power of water throughout our rivers. This has led to flash floods which can jeopardise Scottish peatlands, allowing carbon dioxide to be released into the atmosphere. Essential nutrients will therefore be lost from wetlands and the species found in freshwaters will face the threat of being washed out.

Water Quality & Supply

A team of researchers from CREW, NatureScot, SEPA, Scottish Water, Scottish Government, and the UK Centre for Ecology & Hydrology (UKCEH) collaborated to monitor the water temperature of Scottish lochs and reservoirs between 2015 and 2019. They have now reported a significant increase in water temperatures by 97% and predict temperatures will only continue to rise, spreading to all standing waters across Scotland by 2040. The increased water temperature will make certain lochs and reservoirs more prone to developing water issues – including impacts to the nutrient availability and flushing rates, which will increase their sensitivity to climate change.

With the rise of hotter and drier summers, there is expected to be a change in demand for irrigation across Scotland by 2050. The James Hutton Institute have reported the total volume of water required for irrigation may increase by 30%. Summer droughts will lead to reduced water flow in our freshwater systems, which creates less habitat space for river plants and animals. Lower water flow in Scottish rivers will also allow pollutants to be less diluted and this can reduce the water quality when combined with higher temperatures.

The rise of algal blooms will therefore become a risk in standing waters across Scotland, due to the rapidly warming climate. This negatively affects the users of our lochs and reservoirs as there becomes a higher likelihood for harmful cyanobacteria and toxins to be discharged. This is harmful and so the water quality will become unsuitable for recreational activities like kayaking, whilst no longer remaining a safe habitat for animals. Businesses could also be impacted by the reduction in water quality and as a result, may need to implement rigorous treatments so they can continue to safely operate their natural water supply.

Future Preparation

The real question now is how we can adapt and become better prepared for these future impacts. Experts have claimed that restoring the natural processes in our freshwater systems will allow them to better cope with the changing climate. Natural flood management techniques like wetlands or floodplains will help to reduce flood risk across Scotland – wetlands help to slow down catchment runoff and floodplains will absorb the overspill.

This is a less costly and more sustainable approach to reducing flood risk in Scotland, compared to the use of more engineered solutions like building and maintaining walls or barriers. However, changes in land use, transport infrastructure and business or housing developments, can limit the choice of which approaches are used. Therefore, sometimes a mixture of engineered and natural flood management techniques is more feasible.

Overall, flooding and drought will create significant losses to our economy and livelihoods. As a nation, it is a matter of urgency for Scotland to assess and implement adaptation measures. This will uphold the sustainable use of our freshwaters systems for both the population and nature.

Written by Chloe Sinclair, Climate Change Communications Intern