A world-first system can help better predict the future warming of the world’s lakes due to climate change. It highlights the potential threat to cold-water fish species such as salmon and trout.
Pioneering research led by the UK Centre for Ecology & Hydrology (UKCEH) has devised the first system that classifies lakes globally, placing each of them in one of nine ‘thermal regions’, according to a statement.
Lakes are grouped depending on their seasonal patterns of surface water temperatures, with the coldest thermal region including lakes in Alaska, Canada, northern Russia and China, and the warmest covering lakes in equatorial South America, Africa, India and south-east Asia.
The scientists predict that by the year 2100, for the most extreme climate change scenario, average lake temperature will be around 4 degrees Celsius warmer and that 66 per cent of lakes globally will be classified in a warmer thermal region than they are now.
Professor Stephen Maberly of UKCEH, lead author of the study, explains in the statement: “Thanks to cutting-edge analysis using satellite images of more than 700 lakes, taken twice a month over 16 years, we produced the first global lake temperature classification scheme. By combining this with a lake model and climate change scenarios we were able to identify that northern lakes, such as those in the UK, will be particularly sensitive to climate change.”
Even relatively small changes in temperature can have a significant negative impact on aquatic wildlife, affecting the speed at which organisms grow and feed, and when they reproduce. As species do not react in the same way, prey and predators have increasingly different breeding and feeding cycles, reducing the amount of potential food available.
Warming also increases the risk of harmful algal blooms, which can have a negative impact on aquatic plants and fish.
Photo credit: Benjamin, flickr/Creative Commons