We are now entering the open waters of the Amundsen Sea after a few days sampling in the beautiful fjords of the West Antarctic Peninsula. Above are two photographs of diatom communities from two of our sampling stations. The image on the left depicts diatoms we found in one of the open ocean sites while the image on the right represents a coastal community sample. Can you spot the differences? The coastal sample had many more diatoms because these habitats have plenty of nutrients in the water and they are experiencing 24 hours of light each day.  In contrast the open waters that are further from land have fewer nutrients at the surface.  Even though open water diatoms still get plenty of light, they are nutrient limited, most often for the micronutrient iron.  Diatoms that can live in these habitats often have special adaptations that allow them to continue growing, even when conditions are poor.  On this cruise, we’re sampling diatoms from both regions and will get a chance to examine those special adaptations.  Posted by: Olivia Ahern