A new study out Monday seems to confirm an unpleasant reality: Potentially toxic algae blooms in the world’s freshwater lakes have become more intense over the last 30 years. And while climate change may not be the only reason why blooms have gotten worse, rising temperatures are likely making it harder for lakes to recover from them.

A new study out Monday seems to confirm an unpleasant reality: Potentially toxic algae blooms in the world’s freshwater lakes have become more intense over the last 30 years. And while climate change may not be the only reason why blooms have gotten worse, rising temperatures are likely making it harder for lakes to recover from them.