Project Title

Collaborative Research: A New Approach to Firn Evolution Using the Taylor Dome Natural Laboratory

Summary

Event Number:
I-162-M
NSF / OPP Award 2024163

Program Director:
Dr. Kelly Brunt

ASC POC/Implementer:
Allison Barden / Jenny Cunningham

Principal Investigator(s)

Kaitlin M Keegan
kkeegan@unr.edu
University of Nevada Reno
Reno, Nevada

Location

Supporting Stations: McMurdo Station
Research Locations: Taylor Dome

Description

This project will introduce a new combination of firn datasets designed to facilitate development of next-generation, physics-based firn models. Advances in ice core science and satellite altimetry demand firn models that can reliably simulate firn evolution in a range of climatic conditions and on long and short timescales. Current firn compaction models are largely based on a steady state assumption and tuned to particular geographical locations. Advancing beyond these models requires (1) measuring current firn compaction rates; (2) measuring grain-scale microstructures that play a crucial role in firn compaction; and (3) quantifying processes driving evolution of those microstructures. To decouple the firn’s sensitivities to accumulation and temperature, the team will measure in situ strain rates by two independent methods and observe trends in microstructure in cores from sites spanning the accumulation gradient at Taylor Dome in Antarctica while maintaining the same average temperature. The team will assess the ability of phase-sensitive radar to remotely measure firn compaction rates, potentially simplifying future in situ measurements. This work will create a road map for collecting future microstructural data spanning key areas of temperature accumulation space and simplify future collaborations through the availability of the open-source Community Firn Model.

Field Season Overview

Seven participants, including one Ice Drilling Program (IDP) driller, will deploy to McMurdo Station and then to Taylor Dome from late November to early February. The Antarctic Support Contract field aviation support team will first put in at Taylor Dome and groom a skiway to receive the Basler aircraft that will put in science team members and equipment. At Taylor Dome, the science team will set up camp and focus work around four sites within 6-10 miles of camp. The team will drive radar survey lines connecting the four sites and take phase-sensitive radar (pRES) measurements along the lines, with some autonomous phase-sensitive radar (ApRES) left to collect data over winter. At each site, overwintering "firn observatory" stations will be set up to record weather conditions, borehole temperatures, and firn compaction. The team will collect firn cores from each site using the IDP Eclipse drill. Cores will be transported back to McMurdo Station by Twin Otter and Basler aircraft. Some cores will be analyzed at McMurdo Station, with most shipped north on the United States Antarctic Program cargo vessel.

Deploying Team Members