Blooming phytoplankton discovered under the ice of Antarctica

Antarctica is not exactly a place that is teeming with various forms of life, but a new study suggests cold environments at the world's end may be a bit more hospitable than it seems. Scientists studying sea ice in the Southern Ocean region discovered evidence of widespread phytoplankton blooms.

This discovery came as a surprise to a team led by Dr. Christopher Horvath of Brown University and University of Auckland because the sea ice in the Southern Ocean was considered too dense to let light into the water under him. And since phytoplankton need light to photosynthesize to survive, it was believed that the thick and dense ice sheet typical of the Antarctic winter was simply incompatible with this life form.

Scientists used floats to study conditions in the water column under dense sea ice in Antarctica during the spring and summer between 2014 and 2021. Of these time series measurements, 88% indicated phytoplankton growth prior to sea ice retreat, and 26% indicated that blooms continue under the ice.

To get an idea of ​​how widespread this phenomenon might be, scientists used data from NASA's ICESat-2 satellite to map ice sheets at the poles to within pencil width. Using climate models to calculate the light field under the ice in the Southern Ocean researchers have found that most of it actually has favorable conditions for flowering plankton.