LARISSA

Marine Benthic Ecosystems

Meet the Marine Ecosystem Team

DR. MARIA VERNET Scripps Institution of Oceanography San Diego, California To understand and compare the growth, production and community composition of phytoplankton under the ice shelf, correlated with biological, physical and chemical properties of the water column in the western Weddell sea.

MATTIAS CAPE Graduate Student Scripps Institution of Oceanography San Diego, California Working with Dr. Vernet exploring phytoplankton growth dynamics and their community compositon in the Larsen B embayment. I also want to investigate how the physics and chemistry of the water affect primary production, carbon export to the seafloor and how these values have changed in the Larsen B ice shelf area since its breakup.

DR. CRAIG SMITH Professor of Oceanography University of Hawaii at Manoa Studying colonization and biodiversity of seafloor communities under the Larsen B Ice Shelf. I will also be investigating sediment dwelling communties found around the cold seeps.

LAURA GRANGE Post Doctoral Student University of Hawaii at Manoa Sampling the seabed of the Larsen B embayment and working with Dr. Smith investigating which invertebrate fauna are most abundant. I'm interested in studying how these seabed communities have been affected by climate change. Have their feeding dynamics evolved? How are the reproductive systems of these animals responding to the ecosystems' changes?

DR. MICHAEL MCCORMICK Assistant Professor Hamilton College Clinton, New York To characterize the geochemical and microbial community of the cold seep site in the Larsen B embayment.

DR. MARC DE BATIST Professor Renard Center of Marine Geology University Gent, Belgium Deployment of the remotely-operated vehicle (ROV) for visualization, mapping, and sampling in relation to the measurements of the cold seep structures on the sea floor. We hope to gain a better understand of the physical and geological parameters controlling the venting processes on different time scales.

DR. CINDY VAN DOVER Professor Marine Biology Duke University Marine Laboratory Director Beaufort, North Carolina I am interested in studying the biota of living organisms associated with the cold seeps beneath the Larsen B ice shelf. Studying the seep community will uncover many other animals that live among the vesicomyid clams found here. We are curious if these clams are related to clams in other seep environments? How are the microbes who fuel the system involved in the food web and what role did the ice shelf play in developing this ecosystem.

DAVID HONIG Graduate Student Duke University Marine Laboratory Beaufort, North Carolina I am a graduate student working with Cindy Van Dover to understand the fine-scale food web structure at the Larsen B cold seeps and to characterize the larger role of chemosynthesis in the sub-shelf marine environment both before and after the ice shelf collapse.

BETH SIMMONS Education & Outreach Coordinator Palmer Station, Antarctica LTER Participating in shipboard research, sustaining dialogue between the scientists and the general public, developing web resources that are connected with multimedia and coordinating the development of educational materials.

In an effort to better understand the changes taking place in the Larsen B embayment, the LARISSA project will study connections between the atmosphere, the cryosphere (ice), and ocean. The marine ecosystem team will focus on changes occurring in cold seep communities, the distribution of background seafloor animals, and the dynamics of overlying plankton.

Understanding the structure and function of the ecosystem while the ice cover existed in contrast to the changes the ecosystem is currently undergoing is what drives the lead scientist of the marine ecosystem group, Dr. Vernet and post doctoral candidate Mattias Cape from Scripps Institution of Oceanography. Together they will be exploring the growth, production and changes in the phytoplankton populations within the water column at several different transect locations near the embayment.

Before the ice shelf collapsed, there was permanent ice coverage over the area and low organic carbon input from phytoplankton and perhaps high chemosynthetic input driven by seafloor methane venting. At present, there is open ocean water with high organic carbon input being fed by solar energy from above. "We're seeing a thriving photosynthetic community with phytoplankton production rates similar to other areas around the Weddell Sea," says Vernet. To understand the physical impact of the ice shelf, Vernet and Cape will evaluate the dynamics of how phytoplankton are growing and try to quantify the rate of phytoplankton production from the surface down to various depths in the water column. The chemical properties within the water column (salinity, temperature, and chlorophyll a fluorescence) will all be used to help them identify the characteristics of the surrounding environment.

By comparing the surface communities of phytoplankton to those analyzed within sediment traps at varying depths, they hope to produce a comprehensive view of the phytoplankton communities within this area and the impact of sedimenting debris on seafloor cold seeps. Phytoplankton fuel entire food webs within a marine ecosystem and have an additional role in its structure and function. However, there are other biota living there also.

• Synopsis
• The Marine Ecosystem
• Meet the Marine Ecosystem Team
• More Team Science
• Take it Further: What are Glaciers?
• Online Resources
• Scientific Publications
• Children's Books

Larissa was a figure from Greek mythology, a wife of Poseidon; often pictured holding a vessel having three handles. We think of the three handles as 'Ice/Climate' - 'Marine Geology' and 'Life.'