Study reveals new patterns of key ocean nutrient

The nutrient phosphate may be less abundant in the global ocean than previously thought, according to a new paper in Science Advances. The researchers compiled data collected using sensitive techniques that measure phosphate to create a more accurate dataset to power global ocean models.

"This is a bit of a wake-up call that, as technology advances, we need to update the underlying data and processes that fuel ocean models to ensure they yield the best possible predictions," said Mike Lomas, a senior research scientist at Bigelow Laboratory for Ocean Sciences and an author of the paper. "Models are our best chance to predict the many ways the oceans will respond as climate changes, but our predictions are only as good as the data underlying them."

Lomas and his co-authors found that phosphate in the surface ocean is less abundant than traditional measurements and models suggest. Ocean algae depend on phosphorus, which is essential to all life on Earth. Lower phosphate levels pose challenges for algae, which are predicted to suffer as climate change makes ocean nutrients scarcer.

The researchers compiled high-sensitivity phosphate datasets collected throughout the global ocean, including measurements Lomas collected over nearly two decades of intensive study in the Sargasso Sea. They mapped a new, more accurate dataset, and compared the result to that yielded by more common, lower-sensitivity methods.

"The reality is that we've been operating with a skewed view of ocean phosphate," Lomas said. "With this improvement, we will be able to make our models more realistic and better able to predict this aspect of climate change's impact on our oceans."

"This new view of dissolved phosphorus will be critical to understanding how life is responding to a changing ocean," said Mike Sieracki, a program director in NSF's Division of Ocean Sciences, which funded the research.