A summary of landfast sea ice coverage and the changes in the distance between the penguin colony at Point Geologie and the nearest span of open water on the Adelie Land coast in East Antarctica. The data were derived from cloud-free NOAA Advanced Very High Resolution Radiometer (AVHRR) data acquired between 1-Jan-1992 and 31-Dec-1999. The areal extent and variability of fast ice along the Adelie Land coast were mapped using time series of NOAA AVHRR visible and thermal infrared (TIR) satellite images collected at Casey Station (66.28 degrees S, 110.53 degrees E). The AVHRR sensor is a 5-channel scanning radiometer with a best ground resolution of 1.1 km at nadir (Cracknell 1997, Kidwell 1997). The period covered began in 1992 due to a lack of sufficient AVHRR scans of the region of interest prior to this date and ended in 1999 (work is underway to extend the analysis forward in time). While cloud cover is a limiting factor for visible-TIR data, enough data passes were acquired to provide sufficient cloud-free images to resolve synoptic-scale formation and break-up events. Of 10,297 AVHRR images processed, 881 were selected for fast ice analysis, these being the best for each clear (cloud-free) day. The aim was to analyse as many cloud-free images as possible to resolve synoptic-scale variability in fast ice distribution. In addition, a smaller set of cloud-free images were obtained from the Arctic and Antarctic Research Center (AARC) at Scripps Institution of Oceanography, comprising 227 Defense Meteorological Satellite Program (DMSP) Operational Linescan Imager (OLS) images (2.7 km resolution) and 94 NOAA AVHRR images at 4 km resolution. The analysis also included 2 images (spatial resolution 140 m) from the US Argon surveillance satellite programme, originally acquired in 1963 and obtained from the USGS EROS Data Center (available at: edcsns17.cr.usgs.gov/EarthExplorer/). Initial image processing was carried out using the Common AVHRR Processing System (CAPS) (Hill 2000). This initially produces 3 brightness temperature (TB) bands (AVHRR channels 3 to 5) to create an Ice Surface Temperature (IST) map (after Key 2002) and to enable cloud clearing (after Key 2002 and Williams et al. 2002). Fast ice area was then calculated from these data through a multi-step process involving user intervention. The first step involved correcting for anomalously warm pixels at the coast due to adiabatic warming by seaward-flowing katabatic winds. This was achieved by interpolating IST values to fast ice at a distance of 15 pixels to the North/South and East/ West. The coastline for ice sheet (land) masking was obtained from Lorenzin (2000). Step 2 involved detecting open water and thin sea ice areas by their thermal signatures. Following this, old ice (as opposed to newly-formed ice) was identified using 2 rules: the difference between the IST and TB (band 4, 10.3 to 11.3 microns) for a given pixel is plus or minus 1 K and the IST is less than 250 K. The final step, i.e. determination of the fast ice area, initially applied a Sobel edge-detection algorithm (Gonzalez and Woods 1992) to identify all pixels adjacent to the coast. A segmentation algorithm then assigned a unique value to each old ice area. Finally, all pixels adjacent to the coast were examined using both the segmented and edge-detected images. If a pixel had a value (i.e. it was segmented old ice), then this segment was assumed to be attached to the coast. This segment's value was noted and every pixel with the same value was classified as fast ice. The area was then the product of the number of fast ice pixels and the resolution of each pixel. A number of factors affect the accuracy of this technique. Poorly navigated images and large sensor scan angles detrimentally impact image segmentation, and every effort was taken to circumvent this. Moreover, sub-pixel scale clouds and leads remain unresolved and, together with water vapour from leads and polynyas, can contaminate the TB. In spite of these potential shortcomings, the algorithm gives reasonable and consistent results. The accuracy of the AVHRR-derived fast ice extent retrievals was tested by comparison with near- contemporary results from higher resolution satellite microwave data, i.e. from the Radarsat-1 ScanSAR (spatial resolution 100 m over a 500 km swath) obtained from the Alaska Satellite Facility. The latter were derived from a 'snapshot' study of East Antarctic fast ice by Giles et al. (2008) using 4 SAR images averaged over the period 2 to 18 November 1997. This gave an areal extent of approximately 24,700 km2. The comparative AVHRR-derived extent was approximately 22,240 km2 (average for 3 to 14 November 1997). This is approximately 10% less than the SAR estimate, although the estimates (images) were not exactly contemporary. Time series of ScanSAR images, in combination with bathymetric data derived from Porter-Smith (2003), were also used to determine the distribution of grounded icebergs. At the 5.3 GHz frequency (? = 5.6 cm) of the ScanSAR, icebergs can be resolved as high backscatter (bright) targets that are, in general, readily distinguishable from sea ice under cold conditions (Willis et al. 1996). In addition, an estimate was made from the AVHRR derived fast ice extent product of the direct-path distance between the colony at Point Geologie and the nearest open water or thin ice. This represented the shortest distance that the penguins would have to travel across consolidated fast ice in order to reach foraging grounds. A caveat is that small leads and breaks in the fast ice remain unresolved in this satellite analysis, but may be used by the penguins. We examine possible relationships between variability in fast ice extent and the extent and characteristics of the surrounding pack ice (including the Mertz Glacier polynya to the immediate east) using both AVHRR data and daily sea ice concentration data from the DMSP Special Sensor Microwave/Imager (SSM/I) for the sector 135 to 145 degrees E. The latter were obtained from the US National Snow and Ice Data Center for the period 1992 to 1999 inclusive (Comiso 1995, 2002). The effect of variable atmospheric forcing on fast ice variability was determined using meteorological data from the French coastal station Dumont d'Urville (66.66 degrees S, 140.02 degrees E, WMO #89642, elevation 43 m above mean sea level), obtained from the SCAR READER project ( www.antarctica.ac.uk/met/READER/). Synoptic- scale circulation patterns were examined using analyses from the Australian Bureau of Meteorology Global Assimilation and Prediction System, or GASP (Seaman et al. 1995).

Direct Numerical Simulations are carried out at the ice ocean interface of 1.8 m long, inclined at angles, 50 degree, 65 degree and 90 degree from the horizontal where external source buoyancy is added as a boundary conditions with relative buoyancy B* 5, 7 and 10 times the wall buoyancy. The data set contains 1. Time averaged temperature, salinity and velocity fields of the flow at steady state where averaging windows are several times the respective buoyancy frequency for 90 degree, B* =1, 5,7,10; 50 degree, B*=1, 5, 7 respectively. 2. Tabulated, time averaged along-slope profiles of a) temperature, b) salinity, c) meltrate, d) plume velocity for 90 degree, B* =1, 5,7,10; 65 degree, B* =1, 5,7,10 and 50 degree, B*=1, 5, 7 respectively. 3. Tabulated, domain averaged meltrate, plume velocity for 90 degree, B* =1,3, 5,7,10; 65 degree, B* =1,3, 5,7,10 and 50 degree, B*=1,3, 5, 7 respectively.

An image correlation technique has been applied to RADARSAT ScanSAR images from November in 1997, and November 1999, to create the first detailed maps of fast ice around East Antarctica (75E-170E). This method is based upon searching for, and distinguishing, correlated regions of the ice-covered ocean which remain stationary, in contrast to adjacent moving pack ice. Within the overlapping longitudinal range of ~86E-150.6E, the total fast-ice area is 141,450 km2 in 1997 and 152,216 km2 in 1999. Calibrated radar backscatter data are also used to determine the distribution of two fast-ice classes based on their surface roughness characteristics. The outer boundaries of the determined fast-ice area for November in 1997 and 1999 are contained in the data files for this record. This work has been allocated to ASAC project 3024.

Locations of ice edges on 18 north-south transects of the BROKE voyage of the Aurora Australis (AA V4 1995/96). Locations determined from direct observations by the seabird observers on board. The fields in this dataset are: Latitude Longitude Ice Conditions Transect

During the winter and spring of 2002, underwater calling rates were measured near mid-day on an opportunistic basis at 7 breeding sites and, at two breeding sites, over 24 hour periods once a month. The data were analysed with respect to reproductive season (early ice formation, prebreeding, pupping and mating) and if the recordings were made when it was dark or twilight/light. Taken from the abstract of the paper referenced below: Underwater vocalisation monitoring and surveys, both on ice and underwater, were used to determine if Weddell seals (Leptonychotes weddellii) near Mawson Station, Antarctica, remain under the fast ice during winter within close range of breeding sites. Daytime and nighttime underwater calling rates were examined at seven breeding sites during austral winter and spring to identify seasonal and diel patterns. Seals rarely hauled out at any of the sites during winter, although all cohorts (adult males, females, and juveniles) were observed underwater and surfacing at breathing holes throughout winter (June-September) and spring (October-December). Seal vocalisations were recorded during each sampling session throughout the study (n=102 daytime at seven sites collectively, and n=5 24-h samples at each of two sites). Mean daytime calling rate was low in mid-winter (July) (mean = 18.9 plus or minus 7.1 calls per minute) but increased monthly, reaching a peak during the breeding season (November) (mean = 62.6 plus or minus 15.7 calls per minute). Mean nighttime calling rate was high throughout the winter and early spring (July-October) with mean nocturnal calling rate in July (mean = 61.8 plus or minus 35.1 calls per minute) nearly equal to mean daytime calling rate in November (during 24-h daylight). Reduced vocal behaviour during winter daylight periods may result from animals utilising the limited daylight hours for nonvocal activities, possibly feeding. The following study sites were among those used in this project (provided by Phil Rouget): - Forbes site (identified as Site 6 in the paper) is located at Forbes Glacier (approx. 0.5 km to the west of the glacier tongue and approximately 200 meters offshore of the mainland). (67 degrees 35.256 minutes S, 62 degrees 16.756 minutes E) - Kista site is located in the middle of Kista Strait (site 7 in the Marine Mammal Science paper). (67 degrees, minutes 33.840 S, 62 degrees 47.402, minutes E) - SPA site was our site located just west of the western boundary of the SPA which itself is located west of Mawson and east of Forbes Glacier. (Site 2 in Marine Mammal Science paper). (67 degrees 35.179 S, 62 degrees 25.425 minutes E) - McDonald Islands (or Rocks) was the site located North/NorthWest of Kista Strait, as it is named so on the Framens Mtn. Nautical Chart. From memory, it was approximately 12 km north/north west of Mawson Station. (This was site 5 in the Marine Mammal Science paper). (67 degrees 29.414 minutes S, 62 degrees 41.011 minutes E) - Stewart Rocks (also named Sewart Rocks on an alternative map) is located due north of Mawson Station, also by about 12 km. (East of McDonald site, and North East of Kista). This was site 4 in the Marine Mammal Science paper. (67 degrees 29.933 minutes S, 62 degrees 51.765 minutes E) - Anderson Rocks is an extensive group of rocky islets west of Auster Island (approximately 6-7 km offshore). This was site 3 in the Marine Mammal Science paper. (67 degrees 26.445 minutes S, 63 degrees 25.414 minutes E) - SEAL MO was located just north of Macey Hut by about 2 km. This was site 1 in the Marine Mammal Science paper. (67 degrees 23.399 minutes S, 63 degrees 47.977 minutes E) - Aside from SEAL MO and SPA, the names from all these sites are indicated in the Framnes Mountain Chart. An image showing the locations of the fields sites is also part of the download file. The fields in this dataset are: Site Period Day Calling rate photoperiod Sun time

Imagery of Aurora Australis and sea ice captured by a 'quadcopter' (Inspire) drone launched from the ship

This dataset contains ice motion observations made under the Australian Antarctic Program, Projects 4593 and 4506. Measurements of ice motion where made on (land)fast ice on the eastern rim of the Amery Ice Shelf, Antarctica (69.2 degr. S, 76.3 degr. E) and on landfast ice in Gronfjorden, Svalbard (78.0 degr. N, 14.2 degr. E). Data was obtained using Spotter wave buoys (Sofar Ocean Technologies), hereafter wave buoys, and open-source ice motion loggers, hereafter ice buoys. Instrumentation was deployed on top of the sea ice with the main motivation to measure its vertical motion due to ocean waves. The wave buoys 3-axis measure motion at 2.5 Hz through GPS and have an accuracy of approximately 2 cm for the significant wave height. The ice buoys measure motion in 9-degrees-of-freedom at 10Hz using a VectorNAV VN-100 IMU, accuracy is O(mm) for short waves and O(cm) for long waves. Both instruments also record their geographical location through GPS. Full time series of their motion is processed on board and summaries are send through Iridium. For the wave buoy, this occurred at an interval of 30 minutes. For the ice buoy this occurred every 3 hours. In the dataset, WB and IB are abbreviations for wave buoy and ice buoy, respectively. This dataset covers 2-8 January 2020 for the Antarctic campaign (WB1, WB2, IB1, IB2) and 14-28 March for the Arctic campaign (IB3, IB4, IB5) and includes significant wave height, peak period and the geographical coordinates of the instrumentation. ‘Hs’ refers to significant wave height (in meters). ‘Tp’ refers to peak period (in seconds). Time is in UTC, and in Matlab’s datenum format (i.e. the number of days since year 0000). The geographical coordinates ‘lat’ and ‘lon’ (latitude and longitude, respectively) are in degrees. Note, as the ice buoys transmit the GPS coordinates and wave data in separate data messages, for the ice buoys ‘time’ refers to the reference time of the wave properties Hs and Tp, whereas ‘time_latlon’ refers to the reference time of the geographical coordinates. For the wave buoy, all data is transmitted in one message.

The Antarctic Sea ice Processes and Climate [ASPeCt] data sets submitted here have been collected systematically from the bridge of an icebreaker, while it transited through the pack ice. Quantifiable observations of sea ice thickness and related characteristics of the sea ice, snow, ocean and surface atmosphere are recorded hourly while the vessel moves through the sea ice. If the vessel is stopped or has not moved at least 6nm since the previous observation, no observation will be conducted. The observation protocol has been endorsed by the Scientific Commission for Antarctic Research (under their ASPeCt programme) as the preferred method for conducting ship-based observations of sea-ice characteristics. Details can be found in Worby and Allison [1999] The spreadsheet information below is also included in the word document in the download file. The relevant spreadsheets (xls files) contain the following information: Header name Physical parameter Unit Year Year Date Day/Month/Year Julian Day Day of year Time (UT) Time of day in Universal time: Hours/Minutes/Seconds Lat (oN) Latitude oN Lon(oE) oE Conc Total ice concentration Tenth OW Open-water classification See Worby and Allison [1999] c1 Ice concentration of primary ice category Tenth ty1 Ice type of primary ice category See Worby and Allison [1999] iz1 Thickness of primary ice category cm f1 Floe size of primary ice category See Worby and Allison [1999] t1 Topography of primary ice category See Worby and Allison [1999] s1 Snow type on primary ice category See Worby and Allison [1999] sz1 Snow thickness on primary ice category cm c2 Ice concentration of secondary ice category Tenth ty2 Ice type of secondary ice category See Worby and Allison [1999] iz2 Thickness of secondary ice category cm f2 Floe size of secondary ice category See Worby and Allison [1999] t2 Topography of secondary ice category See Worby and Allison [1999] s2 Snow type on secondary ice category See Worby and Allison [1999] sz2 Snow thickness on secondary ice category cm c3 Ice concentration of tertiary ice category Tenth ty3 Ice type of tertiary ice category See Worby and Allison [1999] iz3 Thickness of tertiary ice category cm f3 Floe size of tertiary ice category See Worby and Allison [1999] t3 Topography of tertiary ice category See Worby and Allison [1999] s3 Snow type on tertiary ice category See Worby and Allison [1999] sz3 Snow thickness on tertiary ice category cm Sea Sea-surface temperature oC Air Surface-air temperature oC

A repository of all ARGOS satellite messages from 1982 to present. Trackers have been used on AWS stations, buoys and numerous species of whales, seals and seabirds. ARGOS is a means of sending data back from PTT devices - Position Tracking Terminals. However, the subject does not necessarily have to be moving - as in the case of the Automatic Weather Stations (AWS), which use ARGOS for relaying meteorological data back to Australia. Animal species that have been or are currently monitored by the Australian Antarctic Program using the ARGOS system include: Grey-headed Albatross Black-browed Albatross Light mantled sooty albatross Australian Fur Seal Antarctic Fur Seal Weddell Seal Ross seal Crabeater seal Southern Elephant Seal Emperor Penguin King Penguin Macaroni Penguin Adelie Penguin Pygmy Blue Whale Locations in which the ARGOS system is/was being used by the Australian Antarctic Program are: Admiralty Bay Albatross Island Almagro Auster Rookery Bechervaise Island Cape Gantheaume Caroline Cove Casey Davis Diego Ramirez Dumont d'Urville, Base Edmonson Point Ildefonso Inexpressible Island Macquarie Island Magnetic Island Pedra Branca Scullin Monolith Shirley Island Spit Bay Taylor Rookery Ufs Island Each day, data is retrieved via telnet client from the ARGOS site in France. A batch process parses the data files and inserts into the Data Centre database by 0800 local time. End-users can subscribe to an email describing the recent data uploads. Web-based tools are provided to filter the data by bounding box, time span and type of message quality. Finally a optional velocity filter can be applied to remove spurious positions that should not be reachable by that particular species. For example, seal data can be filtered for positions that would require speeds in excess of 10 km/hr. The same tool ascribes species, gender, age class and breeding status to each set of data. A separate control allows the filtered data to be published to the general public and/or to OBIS and GBIF via web services. Output products include maps, excel spreadsheets and KML files for mapping data on Google Earth.

This Atlas presents a compilation of AVHRR satellite images of sea ice adjacent to the coast of Eastern Antarctica. It is produced primarily for use by marine and vertebrate ecologists within the Australian Antarctic Division and as a contribution to the CCAMLR Ecosystem Monitoring Program. It is anticipated that this atlas will have value to a wider range of research and other uses including shipping operations. The Atlas provides one good image for each month between 1992 and 1999 for each of 5 regions of Eastern Antarctica centered on the following Antarctic Stations. Mawson station (M) - latitude 67 degrees 36.3 minutes S, longitude 62 degrees 52.2 minutes E Davis station (D) - latitude 68 degrees 34.6 minutes S, longitude 77 degrees 58.3 minutes E Casey station (C) - latitude 66 degrees 17.0 minutes S, longitude 110 degrees 31.2 minutes E Dumont D'Urville station (DD) - latitude 66 degrees 39.8 minutes S, longitude 140 degrees 00.1 minutes E Terra Nova Bay station (TN) - latitude 74 degrees 41.7 minutes S, longitude 164 degrees 07.0 minutes E Each image has been renavigated onto the same projection (Polar stereographic), gridded and a coastline added. Visible and thermal images are provided for the austral summer months, while only a thermal image is provided for the dark winter months. Due to either missing data or the lack of suitable imagery it has not been possible to provide a complete coverage over the period in all regions. Those 500 images presented were culled from some 20,000 images consulted. Images are presented with a schematic map indicating the major divisions of the image into open water, sea ice, cloud, land etc. Each month is accompanied by a short description of the sea ice conditions. The concept of a Sea Ice Atlas for scientific purposes was first proposed in 1999 and funded by the Australian Antarctic Division on the recommendation of the ANARE Mapping and Geographic Information Committee in 1999. Dr Kelvin Michael at IASOS was contracted to supervise the project and produce the Sea Ice Atlas in both hard copy and digital format. The AVHRR data are down loaded at the HRPT receiving facility Australian Antarctic Station of Casey. The HRPT archive is kept at the Antarctic Climate and Ecosystems CRC at the University of Tasmania.