Project Title

Collaborative Research: RAPID: Linking Sea Ice and Biogeochemistry in the Weddell Sea Marginal Ice Zone: Physical Structure, Meltwater, Chemistry and Biological Gradients

Summary

Event Number:
O-409-N
NSF / OPP Award 2532479

Program Director:
Dr. William Ambrose

ASC POC/Implementer:
Kenneth Vicknair / Jamee Johnson

Principal Investigator(s)

Dr. Margaret Anne Mars Brisbin
mmarsbrisbin@usf.edu
University of South Florida
College of Marine Science
St. Petersburg, Florida

Location

Supporting Stations: Research Vessel
Research Locations: Weddell Sea

Description

This project aims to evaluate physical and chemical characteristics of sea ice in the Weddell Sea near Seymour Island and quantify the effects of melting sea ice on phytoplankton growth, zooplankton growth, and carbon export. Sea ice is a key feature of the Southern Ocean, shaping the physical structure of the water column and regulating phytoplankton community dynamics and primary production. Phytoplankton are the base of the food chain, and the type of phytoplankton present, and 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 work promotes the progress of polar science and will allow for better predictions of ecosystem effects from changing sea ice conditions, such as shifts in krill abundance and the krill communities’ ability to support macrofauna and fisheries, as well as changes in carbon export.

Field Season Overview

In 2025-26, five participants will deploy on a University-National Oceanographic Laboratory System (UNOLS) vessel along with the Tobin group (G-296-N). Sampling will take place when the vessel is not supporting science for Tobin. Work will consist of characterizing summer sea ice by measuring sea ice thickness and characteristics. Grantees will conduct conductivity, temperature, depth (CTD) casts for water collection. Surface sediment will be collected, and net tows will be conducted to sample phytoplankton. Additionally, incubation experiments will be conducted to evaluate the effect of varying salinities and nutrient concentrations on biological communities. Participants will deploy to ice floes to sample snow and collect ice cores if conditions permit.

Deploying Team Members