An open access geospatial database for the sub-Antarctic Prince Edward Islands

Researchers of projects at the sub-Antarctic Prince Edward Islands are increasingly considering geospatial data as an essential component in answering scientific questions. A need exists for high-resolution geospatial data in both multi- and transdisciplinary research to better analyse fine-scale biotic–abiotic interactions of the Islands’ landscape and ecosystems within the context of climate change and the impacts of invasive species. However, much of the geospatial data that currently exist have limitations in spatial coverage and/or resolution, are outdated, or are not readily available. To address these issues, we present an online geospatial database for the Prince Edward Islands (both islands) produced from a high-resolution digital surface model and satellite imagery. This database contains vector files, raster data sets, and maps of topographical and hydrological parameters. It is freely available to download from Figshare – an open access data repository. We encourage the South African polar science community to make use of similar platforms for improved data sharing practices. Significance: A topographical and hydrological geospatial database – produced from a 1 m x 1 m digital surface model of the Prince Edward Islands – is provided. These fine-scale geospatial data allow for a more comprehensive assessment of biotic–abiotic interactions at an island scale. Also included are locality maps specifying place names and established long-term marine mammal monitoring beaches and coastal zones for improved cross-referencing. The dataset is downloadable from an open access data repository and intended to promote open science and data sharing practices

Geomorphological processes and landforms of glacier forelands in the upper Aktru River basin (Gornyi Altai), Russia : evidence for rapid recent retreat and paraglacial adjustment

The glaciers in the Aktru River basin of Gornyi Altai, Russia currently represent some of the fastest receding glaciers in the world. Formation of the morainic complexes closest to the contemporary glaciers in the Aktru River basin took place during the 17th - 18th centuries with recession commencing at the end of the 18th century. Coupled with this glacial retreat, earth surface processes and vegetation succession are responding to shape the glacier forelands. This article presents the first geomorphological maps for the upper reaches of the Aktru River basin and focuses on the geomorphological landforms that occur in the rapidly changing glacier forelands. Geomorphological mapping is difficult in steep mountainous regions and, thus, mapping was completed using satellite imagery, field mapping and observations coupled with highresolution aerial photography obtained from Unmanned Aerial Vehicles (UAVs). Critical steps of the procedure used to process UAV imagery and difficulties encountered in this mountainous terrain are noted. The acquired spatial data enable the mapping and classification of small-scale transient geomorphological features such as talus, glacial and glaciofluvial landforms. Their dynamics provide insights into supraglacial and subglacial processes of the glaciers of the Aktru River basin and subsequent paraglacial adjustment. The presented highresolution spatial data, which can also be obtained at high temporal resolutions in the future, can act as a reference frame for geomorphologists and ecologists studying the temporal evolution of glacier forelands of the Aktru River basin during paraglacial adjustment and subsequent colonisation and stabilisation by biota.Incentive Funding for Rated Researchers Programme from the National Research Foundation South Africa, the BRICS Network University International Thematic Groups Seed-Funding and the Tomsk State University Competitive Improvement Programme.https://www.springer.com/journal/116292021-04-11hj2020Geography, Geoinformatics and Meteorolog

Rock mass loss on a nunatak in Western Dronning Maud Land, Antarctica

This paper presents the first rock mass loss data for uncut clasts from continental Antarctica. A rock mass loss experiment using doleritic rock samples was conducted over a seven-year period, between 2008 and 2014, at the Vesleskarvet nunataks, Western Dronning Maud Land. The data show that approximately 10% of clasts suffered a mass loss that is an order of magnitude greater than the remaining 90% of clasts. Thus, the observed rock mass loss is suggested to occur in a series of events that are impossible to predict in terms of frequency and/or magnitude. However, extrapolating from the data obtained during the seven-year period indicates that rates of mass loss are slow and of the order of 1% per 100 years. Direct erosion by wind (including abrasion) as well as mechanical and chemical weathering are suggested to be responsible for rock mass loss. Rock properties, the weathering environment, and a lack of available moisture may be contributing factors to the slow rate of rock decay. This paper suggests that in this area of Antarctica, the slow rate of rock mass loss increases the longevity of existing periglacial landforms such as patterned ground and blockfields, but inhibits development of new patterned ground through the slow production of fines.The Department of Environmental Affairs and the National Research Foundation are gratefully acknowledged for logistical and financial support. This work is published under the NRF/SANAP project : Landscape and climate interactions in a changing sub-Antarctic environment (Grant no 93075).http://instaar.colorado.edu/AAAR/index.phphb2016Geography, Geoinformatics and Meteorolog

A glacial chronology for sub-Antarctic Marion Island from MIS 2 and MIS 3

It is increasingly apparent that local and regional factors, including geographic location, topography and climatic variability, strongly influence the timing and extent of glaciations across the Southern Hemisphere. Glacial chronologies of sub-Antarctic islands can provide valuable insights into the nature of regional climatic variability and the localised response(s) of glacial systems during periods of climatic change. With new cosmogenic 36Cl exposure ages from Marion Island in the southern Indian Ocean, we provide the oldest dated terrestrial moraine sequences for the sub-Antarctic islands. Results confirm that a local Last Glacial Maximum was reached prior to ∼56 ka when ice retreated with localised stand still events at ∼43 ka and between ∼38 and 33 ka. Evidence of ice re-advances throughout MIS 2 are limited and particularly absent for the cooling periods at ∼32 and ∼21 ka, and retreat continued until ∼17 ka ago. Any MIS 1 readvances on the island would be confined to altitudes above 900 m a.s.l. but the Holocene exposure ages remains to be documented. We compare Marion Island's glacial chronology with other sub-Antarctic islands (e.g., the Kerguelen archipelago, Auckland and Campbell islands and South Georgia) and review the evidence for a Southern Hemisphere glacial maximum in late MIS 3 (∼41 ka). At a regional scale we recognize sea surface temperatures, sea ice extent and the latitudinal position of the Southern Westerly Wind belt as key controls on equilibrium-line altitudes and ice accumulation due to their influence on air temperature and precipitation regimes. At an island scale, geomorphological mapping shows that deglaciation of individual glacier lobes was a-synchronous due to local physiographical and topographical factors controlling the island's micro-climate. We suggest that variability in deglaciation chronologies at smaller scales (particularly at the sub-Antarctic Islands) are important to consider when untangling climatic drivers across the Southern Ocean

A community-based geological reconstruction of Antarctic Ice Sheet deglaciation since the Last Glacial Maximum

A robust understanding of Antarctic Ice Sheet deglacial history since the Last Glacial Maximum is important in order to constrain ice sheet and glacial-isostatic adjustment models, and to explore the forcing mechanisms responsible for ice sheet retreat. Such understanding can be derived from a broad range of geological and glaciological datasets and recent decades have seen an upsurge in such data gathering around the continent and Sub-Antarctic islands. Here, we report a new synthesis of those datasets, based on an accompanying series of reviews of the geological data, organised by sector. We present a series of timeslice maps for 20ka, 15ka, 10ka and 5ka, including grounding line position and ice sheet thickness changes, along with a clear assessment of levels of confidence. The reconstruction shows that the Antarctic Ice sheet did not everywhere reach the continental shelf edge at its maximum, that initial retreat was asynchronous, and that the spatial pattern of deglaciation was highly variable, particularly on the inner shelf. The deglacial reconstruction is consistent with a moderate overall excess ice volume and with a relatively small Antarctic contribution to meltwater pulse 1a. We discuss key areas of uncertainty both around the continent and by time interval, and we highlight potential priorit. © 2014 The Authors

The changing demography of academic staff at higher education institutions (HEIs) in South Africa

In this work, we contribute to the debate on the transformation of higher education institutions (HEIs) in post-apartheid South Africa by examining the changing demography of academic staff bodies at 25 South African HEIs from 2005 to 2015. We use empirical data to provide initial insights into the changing racial profiles of academic staff bodies across age, gender and rank and then summarise our findings into a transformation ‘scorecard’ which provides an indication of how all racial groups in the country are performing in terms of their representation in higher education. Initial results indicate that most academics in South Africa are middle-aged (between 35 and 54) but an ageing trend is evident, particularly among white academics. In terms of gender, males marginally outnumber females, although we estimate an equitable distribution to be attained within the next 5 years. Significantly, the data indicate that there is an upwards trajectory of black African academics across all rankings from 2005 to 2015 and a concomitant downward trajectory of white academics across all rankings. Both Indian and coloured academics most closely represent their national population representation. Our transformation ‘scorecard’ indicates that the demography of academic staff at higher education institutions in South Africa is changing and will continue to change in the future, particularly within the next 20 years if current trends continue.http://link.springer.com/journal/107342019-07-01hj2017Geography, Geoinformatics and Meteorolog

The glacial geomorphology of sub-Antarctic Marion Island

Since the discovery of glacial features on sub-Antarctic Marion Island, the character and extent of a historic glacial period have remained an important research focus for earth science investigations. Previous glacial reconstructions were limited to mostly pre-GPS field observations and pre-digital mapping through a Geographic Information System. With the aid of GPS field mapping, high-resolution satellite imagery and a digital surface model with a 1 × 1 m cell resolution, this paper provides a comprehensive, geo-rectified spatial geodatabase and map of Marion Island’s glacial geomorphology. The geodatabase includes an inventory of glacial erosional (e.g. striations) and depositional (e.g. moraines) features compiled from existing records as well as new features mapped from recent field observations. The final map and the geodatabase, which is downloadable as ESRI layer-package files, will aid future field investigations and modelling applications to understand Marion Island’s Quaternary landscape evolution and post-glacial ecological succession

Aeolian processes and landforms in the sub-Antarctic: Preliminary observations from Marion Island

Sub-Antarctic Marion Island has a hyperoceanic climate, with cold and wet conditions and consistently strong wind velocities throughout the year. Recent observations recognized the increasing role of aeolian processes as a geomorphic agent, and this paper presents the first data for transport by aeolian processes on a sub-Antarctic island. Data were collected through an intensive and high-resolution measurement campaign at three study sites using Big Spring Number Eight sediment traps and surface sediment samplers in conjunction with an array of climatic and soil logger sensors. Observed aeolian landforms are megaripples, and the data suggest that aeolian processes are also modifying solifluction landforms. The sediment traps and sediment samplers collected wind-blown scoria at all three study sites, and the annual (horizontal) aeolian sediment flux extrapolated from this preliminary data is estimated at 0.36–3.85 kg cm−2 y−1. Importantly, plant material of various species was trapped during the study that suggests the efficiency of wind for the dispersal of plants in this sub-Antarctic environment may be underestimated. This paper advocates long-term monitoring of aeolian processes and that the link between aeolian processes and synoptic climate must be established. Furthermore, wind as a means to disperse genetic material on Marion Island should be investigated.Keywords: Marion Island; climate change; wind; erosion; dispersal.(Published: 23 November 2015)Citation: Polar Research 2015, 34, 26365, http://dx.doi.org/10.3402/polar.v34.2636

The academic staff profile of geographers at higher education institutions (HEIs) in South Africa : the challenges for transformation

South Africa’s first national democratic elections in 1994 marked a turning point in the history of the country. Since democracy much of the focus of African National Congress (ANC)-led government has been on redress and transformation across all spheres of society, including higher education. This paper examines one important aspect inherent in transforming higher education; that is, changing the academic staffing profile of its institutions to more accurately reflect the demographics of the country. Specifically, we examine the academic staffing profiles (gender, race, and rank) of Geographers employed at higher education institutions (HEIs) in South Africa and compare these statistics to national academic staffing trends. Results indicate that Geographers in South Africa are most often white and male although these findings mirror national percentages. We also found a paucity of black African Geographers at more senior academic positions as well as a lack of black African female Geographers. Racial inequities in the distribution of academic staff were noted with white male Geographers disproportionately located at historically white institutions while black African Geographers are disproportionately located at historically black institutions. We discuss these, and other results, in the broader context of the transformation of the discipline of Geography in South Africa.https://www.tandfonline.com/loi/cjgh20hj2022Geography, Geoinformatics and Meteorolog

A survey of Great-winged Petrels Pterodroma macroptera breeding at sub-Antarctic Marion Island and a revised global population estimate

Although burrow-nesting petrels are the most abundant group of seabirds in the Southern Ocean, their global populations are poorly known,  because most species breed on remote islands. For example, there are no accurate estimates for Great-winged Petrel Pterodroma macroptera populations at any of its major breeding sites. Moreover, current global population estimates for Great-winged Petrels of approximately 1.5 million birds include counts of the closely related Grey-faced Petrel P. gouldi, which is now recognised as a different species. On sub-Antarctic Marion Island, Great-winged Petrel burrows found within random strip transects were counted and then burrow densities were extrapolated by GIS-derived habitat attributes to generate an island-wide burrow estimate (33 000 burrows). Burrow occupancy rates at the start of incubation averaged 48 ± 29% (range 10–94%) during one-off surveys at ten sites around the island, and repeat surveys found at least 42% of burrows were occupied by breeders. This suggests there were approximately 14 000 occupied burrows (95% CI 9 500–18 500) on Marion Island in 2015. Collating data from other breeding sites suggests that the global breeding population is perhaps 100 000–150 000 pairs (400 000–600 000 birds). Estimation de la population de Pétrel Noirs se reproduisant sur l’île sub-Antarctique Marion et révision de la population mondiale Bien que les pétrels reproduction hypopgée représentent le groupe le plus abondant des oiseaux de mer de l’Océan Austral, leurs abondances  réelles sont rarement connues car la plupart des espèces se reproduisent sur les îles isolées. Par exemple, il n’existe aucune estimation précise des populations de Pétrel Noir Pterodroma macroptera sur aucune de leurs colonies majeures de reproduction. De plus, la population globale qui est actuellement estimée à 1.5 million d’oiseaux, inclut également les populations de Pétrel à face grise P. gouldi, espèce qui est maintenant reconnue comme une espèce à part entière. Un comptage des terriers de Pétrel Noirs sur l’île sub-Antarctique Marion a été réalisé par la méthode de transects choisis aléatoirement. La densité globale pour l’île a ensuite été extrapolée par SIG en tenant compte des caractéristiques des habitats potentiels de l’île (33 000 terriers). En début d’incubation, l’occupation des nids observée sur 10 sites tout autour de l’île était en moyenne de 48 ± 29% (intervalle 10–94%). Des contrôles répétés ont montré que 42% de ces terriers étaient occupés par des oiseaux reproducteurs. Cette estimation suggère un nombre de terriers occupés d’environ 14 000 (95% intervalle de confiance 9 500–18 500) pour l’île Marion en 2015. Additionné aux  données des autres sites de reproduction, cela suggère une population mondiale estimée à 100 000–150 000 couples reproducteurs (400 000–600 000 oiseaux). Keywords: burrow-nesting petrel, Grey-faced Petrel P. gouldi, nest surveys, random transects, seabird