1. Ecosystem Earth Observation, CSIR; Stellenbosch South Africa
2. Department of Oceanography, Nansen-Tutu Center for Marine Environmental Research; University of Cape Town; Cape Town South Africa
3. Southern Ocean Carbon and Climate Observatory, CSIR; Stellenbosch South Africa
4. Department of Oceanography; University of Cape Town; Cape Town South Africa
5. Now at Department of Marine Sciences; University of Gothenburg; Gothenburg Sweden
6. Univ. Brest; CNRS, IRD, Ifremer, Laboratoire d'Océanographie Physique et Spatiale (LOPS), IUEM; Brest France