Reconstructing Carbon-14 of Atmospheric Carbon Monoxide from Law Dome, Antarctica
This project will sample firn air and shallow ice to a depth of about 233 meters at the Law Dome high-accumulation coastal site in East Antarctica. The goal of the project is to obtain measurements of paleo-atmospheric carbon-14 of carbon monoxide back to the 1800s. These measurements will help to constrain changes in the oxidizing capacity of the atmosphere during the industrial period. The Badger-Eclipse Drill will be used to create the borehole for the firn air sampling. The 4-Inch Drill and Blue Ice Drill - Deep will be used to collect the ice core samples.
Radio and Optical Measurements of Glacial Ice Properties Using the SPICEcore Borehole
This project will utilize the Intermediate Depth Logging Winch to lower a series of optical+UV and radio sensor packages into the South Pole Ice Core (SPICEcore) borehole to the full depth of the hole (1751 m). The science goals include measurements of the radio absorption length of the ice from 100-1000MHz, radio birefringence in the ice, and ice index of refraction, all measured as a function of depth and ice temperature. The science team is interested in the optical scattering, absorption lengths, and luminescence as a function of depth and optical wavelength from the visible into the ultraviolet.
LTER: Ecosystem Response to Amplified Landscape Connectivity in the McMurdo Dry Valleys, Antarctica
The McMurdo Dry Valleys Long-Term Ecological Research (MCM-LTER) Program is an interdisciplinary and multidisciplinary study of the aquatic and terrestrial ecosystems in an ice free region of Antarctica. The MCM-LTER has studied Dry Valleys ecosystems since 1993 and observed their responses to climate variations over time. Landscape connectivity, such as streams connecting glaciers to lakes, and lake level rise connecting upland soils, is recognized to be influenced by climate and geological drivers. This physical connectivity facilitates biotic linkages and enables gene flow among the endemic microbial communities. Researchers hypothesize that increased ecological connectivity within the Dry Valleys will amplify exchange of biota, energy, and matter, homogenizing ecosystem structure and functioning. During the MCM-LTER program, researchers will examine (a) how climate variation alters connectivity among landscape units, and (b) how biota (species, populations, and communities) are connected across this heterogeneous landscape, using state-of-the-art science tools and methods, including ongoing and expanded automated sensor networks, analysis of seasonal satellite imagery, biogeochemical analyses, and next-generation sequencing. Research will use the Sediment Laden Lake Ice Drill to make holes in the permanent lake ice of the McMurdo Dry Valleys for access to deployed equipment and melting out cables in the ice.
Extent of Firn Aquifers on the Antarctic Peninsula
Snow or firn aquifers are areas of subsurface meltwater storage that form in glaciated regions experiencing intense summer surface melting and high snowfall. Aquifers can induce hydrofracturing, and thereby accelerate flow or trigger ice-shelf instability leading to increased ice-sheet mass loss. Widespread aquifers have recently been discovered in Greenland. These have been modelled and mapped using new satellite and airborne remote-sensing techniques. In Antarctica, a series of catastrophic break-ups at the Wilkins Ice Shelf on the Antarctic Peninsula that was previously attributed to effects of surface melting and brine infiltration is now recognized as being consistent with a firn aquifer--possibly stimulated by long-period ocean swell--that enhanced ice-shelf hydrofracture. This project will verify inferences (from the same mapping approach used in Greenland) that such aquifers are indeed present in Antarctica. The team will survey two high-probability sites: the Wilkins Ice Shelf, and the southern George VI Ice Shelf.
This study will characterize the firn at the two field sites, drill shallow (~60 m maximum) ice cores, examine snow pits (~2 m), and install two AMIGOS (Automated Met-Ice-Geophysics Observing System) stations that include weather, GPS, and firn temperature sensors that will collect and transmit measurements for at least a year before retrieval. Ground-penetrating radar survey in areas surrounding the field sites will track aquifer extent and depth variations. Ice and microwave model studies will be combined with the field-observed properties to further explore the range of firn aquifers and related upper-snow-layer conditions.
RAID Maintenance Efforts during 2018-2019 Antarctic Field Season
The 2018-2019 field season for the Rapid Access Ice Drill (RAID) project will consist of maintenance and upgrades only, with no testing of ice drilling. Upon request by the PIs, IDP is deploying one engineer to serve as the team leader for the maintenance season.