Browsing by Author "Froneman, P. William"

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    Conclusion : change in terrestrial and marine systems
    (AFRICAN SUN MeDIA, 2008) Chown, Steven L.; Froneman, P. William
    ENGLISH SUMMARY : The modern climate of the Prince Edward Islands has been described as one of the most oceanic and stable on earth (Schulze 1971; Van Zinderen Bakker 1978; le Roux 2008). Indeed, on the basis of the typically low daily amplitude of temperatures and their small variation between summer and winter, this characterization is correct. However, over both longer and shorter timescales, stability is something of a caricature. The islands have changed dramatically over the course of their history. Although much remains to be learned about the sequence of glaciation and volcanism on both islands (Boelhouwers et al. 2008), it is clear that they underwent considerable modification as a result of changing global climates and isostatic adjustment that was a consequence thereof.
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    Nutrient dynamics in the vicinity of the Prince Edward Islands
    (AFRICAN SUN MeDIA, 2008) Smith, Valdon R.; Froneman, P. William
    Nutrient concentrations in the open waters of the Polar Frontal Zone (PFZ) are highly variable, reflecting the region’s complex oceanographic regime. Surface concentrations of nitrate, silicate and phosphate range from 9.5 to 97.5, from 0.2 to 16.5 and from < 0.1 to 16.6 mmol m-3, respectively (Allanson et al. 1985; Duncombe Rae 1989; Ismail 1990; Balarin 2000). Changes in nutrient concentrations coincide with the intrusion of Antarctic surface water from the south and sub-Antarctic surface water from the north (Ansorge et al. 1999; Froneman et al. 1999). Mesoscale features such as far field eddies or the eddies generated by the interaction between the Antarctic Circumpolar Current (ACC) and the South-West Indian Ridge further contribute to the heterogeneity in nutrient concentrations within the surface waters of the PFZ (Ansorge & Lutjeharms 2002, 2003; Ansorge et al. 2004).
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    The Prince Edward Islands in a global context
    (AFRICAN SUN MeDIA, 2008) Chown, Steven L.; Froneman, P. William
    The history of the planet is one of change. Continental positions have moved, sea-levels have advanced and retreated, mountains have been formed and eroded, climates have varied from warm to cool and back again, and life has responded to and sometimes driven these processes, with species and higher taxa waxing and waning for the last several billion years (Stanley 1989; Behrensmeyer et al. 1992). More recently, humans have come to influence these changes. Our recent history has been one of significant effects on the abiotic environment, including elevation of atmospheric greenhouse gas concentrations, depletion of stratospheric ozone, and alterations to the global climate (Watson 2002; Domack et al. 2005). In turn, changing climates have had and continue to have profound effects on biodiversity, ranging from population and species loss (Pounds et al. 2006) to alterations in species distributions, changes in phenology, and shifts in ecological regimes (Walther et al. 2002; Parmesan & Yohe 2003; Root et al. 2003).
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    South African research in the Southern Ocean : new opportunities but serious challenges
    (Academy of Science of South Africa, 2013) Treasure, Anne M.; Moloney, Coleen L.; Bester, Marthan N.; McQuaid, Christopher D.; Findlay, Ken P.; Best, Peter B.; Cowan, Don A.; De Bruyn, P. J. Nico; Dorrington, Rosemary A.; Fagereng, Ake; Froneman, P. William; Grantham, Geoff H.; Hunt, Brian P. V.; Meiklejohn, Ian; Pakhomov, Evgeny A.; Roychoudhury, Alakendra N.; Ryan, Peter G.; Smith, Valdon R.; Chown, Steven L.; Ansorge, Isabelle J.
    South Africa has a long track record in Southern Ocean and Antarctic research and has recently invested considerable funds in acquiring new infrastructure for ongoing support of this research. This infrastructure includes a new base at Marion Island and a purpose-built ice capable research vessel, which greatly expand research opportunities. Despite this investment, South Africa’s standing as a participant in this critical field is threatened by confusion, lack of funding, lack of consultation and lack of transparency. The research endeavour is presently bedevilled by political manoeuvring among groups with divergent interests that too often have little to do with science, while past and present contributors of research are excluded from discussions that aim to formulate research strategy. This state of affairs is detrimental to the country’s aims of developing a leadership role in climate change and Antarctic research and squanders both financial and human capital.