Keynote Speaker
Dr Eckart Schumann
Department of Geosciences, Nelson Mandela University, Gqeberha, South AfricaSpeech Title: The Agulhas Current off southeast South Africa: options for power generation and OTE.
Abstract: The Agulhas Current is a major western boundary current flowing polewards off the southeast coast of South Africa and represents a substantial untapped source of energy. As a requirement of the dynamics, the Current core lies just offshore of the continental shelf break, and since this section of coastline is relatively straight with a narrow shelf, it means that access is facilitated.
Extensive current measurements have been made along the inshore boundary of the Agulhas Current, confirming the presence of consistent currents generally flowing at more than 1.2 m/s over a coastline extent of more than 400km. Nonetheless, the strongest currents occur higher up in the water column, which means that turbines deployed to extract the power need to be situated (floating) at heights of around 50m above the seabed in water depths near to 100m. The technology to do this is being developed.
While the currents generally flow southwest-wards, major perturbations occur once or twice a year in the form of ‘Natal Pulses’, which can reverse and minimise the currents for more than 10 days. However, these Natal Pulses can be identified in satellite imagery, giving advance warning of a few days before the currents change.
The Agulhas Current also transports large volumes (>70 x 106 m3/s) of oceanic water from the subtropics to the northern regions of the coastal province of KwaZulu-Natal. As such surface water temperatures, even in winter, are generally greater than 22 °C, while at 1000 m depth temperatures seldom exceed 5 °C. The narrow shelf interspersed with deep canyons makes for suitable oceanographic conditions for the operation of ocean thermal energy conversion.
Biography: Eckart Schumann has BSc and BSc (Hons) from the University of KwaZulu-Natal (UKZN), MSc from the University of South Africa, MSc from Cambridge University and a PhD from UKZN. He has published more than 70 papers in international refereed journals and books, edited a book, presented more than 50 papers at international conferences, and written more than 100 reports and contract reports on various aspects of coastal and estuarine dynamics, weather and climate, as well as a number of popular articles.
He has been involved with a number of South African research programmes as member and leader, as well as representing South Africa on international bodies such as IUGG, IAPSO, SCOR and CORPWIO. In 1982 he was a guest investigator at WHOI.
He was Head of the Physical Oceanography Division of the National Research Institute for Oceano logy NRIO, CSIR, and Alternate to the Director, Marine Sciences before joining the new Department of Oceanography at Nelson Mandela University (NMU). As such he has undertaken numerous scientific cruises and is a scientific diving instructor with more than 300 dives. He retired from NMU in 2000 and has continued as a Research Associate while doing consulting work.