Lake surface water temperature can increase considerably in response to climate change, leading to unprecedented shifts in lake thermal habitat and consequently in lake ecosystem functioning. The implications of lake warming are particularly severe when temperatures rise to extreme levels. Such conditions occur, by definition, during lake heatwaves - periods of extreme hot lake surface water temperatures. Here I use satellite observations and numerical models to investigate changes in lake heatwaves worldwide under historic and future climate change. I show global warming can result in a global increase in the frequency, intensity, and duration of lake heatwaves, an increase in their spatial extent, and increase the minimum horizontal distance that must be travelled away from a heatwave to track historic surface temperatures. Furthermore, evidence suggests that the occurrence probabilities of lake heatwaves have increased substantially due to human-influence. Observed and projected changes in these heatwave attributes could have a dramatic influence on lake ecosystems, resulting in numerous negative impacts on the many benefits that lakes provide to society, including the provision of safe water for drinking and irrigation, recreational use, and economic benefits such as fisheries and tourism.

Tutorial/Invited: Invited

Primary Presenter: R. Iestyn Woolway, Bangor University (iestyn.woolway@bangor.ac.uk)

Authors:

R. Iestyn Woolway, Bangor University  (Iestyn.woolway@bangor.ac.uk)