Climate change could transform ocean plankton into carbon emitters.

A new study warns that a warming climate could cause globally abundant mixotrophic microbes to shift from being carbon sinks to carbon emitters, potentially triggering climate change tipping points. Mixotrophic microbes are organisms that can switch between photosynthesizing like plants and eating like animals. The researchers' model also revealed that right before mixotrophic microbe communities switch to emitting carbon dioxide, their abundance starts to fluctuate wildly, which could act as early warning signals for climate change tipping points. However, these early warning signals can be muted by increases of nutrients like Nitrogen to the environment, typically caused by run off from agriculture and wastewater treatment facilities.