Metadata record for data from ASAC Project 2581 See the link below for public details on this project. The break-up of Antarctic ice shelves has highlighted the need for a better understanding of the dominant fracture processes occurring within the ice shelves and whether there is any link to climate variability. Using a combination of in-situ (GPS, seismic) and satellite (optical and radar imagery, synthetic aperture radar (SAR)) measurements and airborne ice radar measurements, we will quantify the deformation and fracture processes in different regions on the Amery Ice Shelf, leading to improved fracture mechanics models. GPS measurements were taken across large crevasses in the shear margins on the eastern side of the Amery Ice Shelf, north of Gillock Is. These measurements will give us an opportunity to measure the three dimensional deformation across active fracture zones, leading to a better understanding of fracture processes on ice shelves. Three GPS networks, each network consisting of 4 GPS units in a quadrilateral shape, were measured over the period 17-28 Jan, 2007. These data will be processed during 2007 to compute the deformation and strain across and within the crevassed areas.

Amery Ice Shelf AM04 borehole drilled mid-January 2006. Sub-shelf water profiling measurements conducted over a period of a few days. Partial video recording of borehole walls and sea floor benthos. Collection of targeted ice core samples. Sediment sample collected from sea floor. Long term monitoring instruments installed (thermistors in ice, 3 x CTD in ocean cavity). This is a parent record - see the child records for further information. This device stopped working by the 2011/2012 season, and all sensors were declared non-functional.

Amery Ice Shelf AM03 borehole drilled mid-December 2005. Sub-shelf water profiling measurements conducted over a period of a few days. Partial video recording of borehole walls and sea floor benthos. Sediment sample collected from sea floor. Long term monitoring instruments installed (thermistors in ice, 3 x CTD in ocean cavity). This is a parent record - see the child records for further information.

Ocean circulation beneath ice shelves and associated rates of melting and freezing are influenced strongly by water column thickness and depth. The shape of the cavity beneath the Amery Ice Shelf is important for our understanding of ice shelf stability and freshwater input to the ocean and their dependence on climate. New seismic surveys of the centre region of the Amery Ice Shelf and ice-draft data taken at the grounding line has provided a considerable amount of new water-column thickness and bathymetry data. The data is adjusted in the unknown region south of 71 degrees 35 minutes S by comparing the complex error between simulated tides against in situ GPS observations. A finite element, hydrodynamic ocean tide model is used to simulate the 4 major constituents (S2, M2, K1 and O1). The new data differs from a previous bathymetry map in a number of places. Significantly, there is channel that leads from the Prydz bay depression into the deepest part of the AIS cavity in the south through a series of depressions. This technique has particular application when the water column beneath ice shelves is inaccessible and in situ GPS data is available.

Amery Ice Shelf AM03 borehole drilled mid-December 2005. Sub-shelf water profiling measurements conducted over a period of a few days. Partial video recording of borehole walls and sea floor benthos. Sediment sample collected from sea floor. Long term monitoring instruments installed (thermistors in ice, 3 x CTD in ocean cavity). There are several video files attached to this metadata record, and further details about them are provided in the accompanying readme document.

Amery Ice Shelf AM06 borehole drilled early January 2010. Sub-shelf water profiling measurements conducted over a period of a few days. Partial video recording of borehole walls and sea floor benthos. Collection of targeted ice core samples. Sediment sample collected from sea floor. Long term monitoring instruments installed (thermistors in ice, 3 x CTD in ocean cavity). This is a parent record - see the child records for further information, and access to the data. Some general readme documents are available for download from the provided URL.

Amery Ice Shelf AM04 borehole drilled mid-January 2006. Sub-shelf water profiling measurements conducted over a period of a few days. Partial video recording of borehole walls and sea floor benthos. Collection of targetted ice core samples. Sediment sample collected from sea floor. Long term monitoring instruments installed (thermistors in ice, 3 x CTD in ocean cavity). There are several video files attached to this metadata record, and further details about them are provided in the accompanying readme document.

Amery Ice Shelf AM05 borehole drilled mid-December 2009. Sub-shelf water profiling measurements conducted over a period of a few days. Partial video recording of borehole walls and sea floor benthos. Collection of targeted ice core samples. Sediment sample collected from sea floor. Long term monitoring instruments installed (thermistors in ice, 3 x CTD in ocean cavity). This is a parent record - see the child records for further information. Some general readme documents are available for download from the provided URL.

High resolution digital aerial photography of Adelie penguin colonies, Davis Station, Heidemann Valley, and other various areas, LIDAR scanning of portions of the Vestfold Hills, Rauer Islands and sea ice in front of the Amery Ice Shelf, conducted from 2009/11/17 to 2009/11/23. Some of the aerial photography has been conducted in support of various AAS projects: AAS 3012 (ASAC_3012) AAS 2722 (ASAC_2722) AAS 1034 (ASAC_1034) AAS 3130 (ASAC_3130) A short list of the work carried out: - Long duration over water/sea ice flights for the purposes of "Investigation of physical and biological processes in the Antarctic sea ice zone during spring using in situ, aircraft and underwater observations". - Over-flights at 750m over specific islands in the Vestfold Hills and Rauer Islands known to hold Adelie colonies. - Transects of flights were performed over Davis station, at 500m altitude, taking photos and LIDAR measurements. - The evaluation of the APPLS equipment (camera, LIDAR, electronics, software) was performed and in parallel to the other tasks. - Production a digital elevation model of the Heidemann Bay Area. - Aerial photography / LIDAR of moss beds in the Vestfold Hills area. - The Marine Plain area, south east of Davis, was mapped using LIDAR and aerial imagery for the purposes of general Antarctic information. - The Vestfold Lakes, particularly Lake Druzby, Watts Lake, Lake Nicholson and Crooked Lake provide interesting aerial imagery. - The opportunity was taken to visit the plateau skiway (at 'Woop woop') and estimate the effort in opening the skiway later in the season. - Fly over and photograph the length of the resupply fuel hose from the AA to the shore. - The Russian 'Progress 1 and 2', and Chinese Zhong Shan stations were over flown and aerial imagery collected. Taken from the report: This document describes the results of the use of the APPLS (Aerial Photographic Pyrometer Laser System) at Davis during resupply 2009/2010 (November 17 to 24, 2009). This document is primarily for Science Technical Support use. Portions of the report can be used to provide information on the results obtained to other parts of AAD.