Sea ice is a key feature of the Southern Ocean that shapes the physical structure of the water column and regulates phytoplankton community dynamics and primary production. Phytoplankton are the base of the food chain, and the type of phytoplankton present, along with their overall productivity, impact the abundance of zooplankton and larger animals. Phytoplankton communities and production are also an important link for carbon export to the deep sea, a critical service provided by the Southern Ocean. However, sea ice extent and duration are decreasing in the Antarctic Peninsula region of the Southern Ocean, potentially affecting carbon export. This project aims to evaluate physical and chemical characteristics of sea ice in the Weddell Sea near Seymour Island and quantify effects of melting sea ice on phytoplankton and zooplankton growth and carbon export. This work will promote the progress of polar science and allow for better predictions of the ecosystem effects of changing sea ice conditions, such as shifts in krill abundance and its ability to support macrofauna and fisheries, and changes in carbon export. This project will further support the training of new undergraduate and graduate polar scientists and confer key transferable skills, such as data analysis and visualization and science communication. This project brings together an interdisciplinary team of physical, chemical, and biological oceanographers to comprehensively evaluate characteristics of sea ice i