The Dead Zones: If Only They Could See the Future

SciShort_11_29_15New research released by OSU suggests a strong link between sudden ocean warming which took place after the last ice age and large swathes of ocean that were marked by low oxygen levels and a dearth of marine life.

Sorry, let me put that more succinctly: ocean dead zones.

The study found a clear link between the rising temperature and a die off and sinking of plankton, which led to hypoxia (low oxygen) throughout the dead zones.

Summer Praetorius, lead author on the study and doctoral student at OSU, commented on the link in a press release.

“Our study reveals a strong link between ocean warming, loss of oxygen, and an ecological shift to favor diatom production. During each warming event, the transition to hypoxia occurred abruptly and persisted for about 1,000 years, suggesting a feedback that sustained or amplified hypoxia,” said Praetorius.

The data in the study came from sediment cores collected over decades from the North Pacific. They took the temperature readings from biomarkers, tiny organic molecules in the sediment.

Alan Mix is a professor at OSU’s College of Earth, Ocean and Atmospheric Studies (CEOAS) and co-author on the study. He explains in the same press release how the warming leads to the diatom plankton bloom, which die and sink, eating up oxygen, and leading to the dead zones. But more importantly he comments on what this all tells us about climate change’s effects.

“Many people have assumed that climate change impacts will be gradual and predictable,” said Mix, “but this study shows that the ecological consequences of climate change can be massive and can occur pretty fast, with little warning.”

 Remember this next time you see a person with a panicked look describing a two-degree rise in water temperatures and you think to yourself, “That doesn’t sound like much…”

By Sidney Reilly