Question: Is climate change affecting lakes? And how dramatically would humans be affected if lakes were to be significantly damaged?

Steve Thackeray answered on 17 Jun 2020: last edited 17 Jun 2020 12:11 pm

This is a great question. We know from long records of lake conditions (from lakes across the world) that climate change is already having effects on these ecosystems. The overall picture is complicated, but some examples of effects are:

– earlier ice melting each year, for lakes in Arctic areas, and rising water temperatures
– changes in the way that lake water mixes through the year, because of changes in water temperature
– changes in the time of year at which lake wildlife grows and reproduces (because increasing temperatures can “speed up” their life cycles)
– more frequent algal blooms (so, green paint-like scums on the water surface)
– loss of habitat for species that prefer cold water. For example, some fish prefer cold, oxygen-rich water and warming can lead to the loss of this habitat.

All of these changes could affect humans. For example, more algal blooms (because of climate change) can make water unsuitable for swimming (some algae produce toxins that can make humans, pets, livestock ill). These blooms would mean that water companies would have to treat the water to keep us healthy, and this might make our water bills more expensive. In other parts of the world, with poorer water treatment, this could be a big health issue. Also, the loss of some cool-water wildlife could affect people’s enjoyment of the environment (including activities like fishing), and then tourism and the economy. Again, in some parts of the world, we might be losing species that people depend on for food and their livelihoods.