| Title | State of the marine environment off South Africa: December 2008 |
|---|---|
| Authors |
Oceans and Coastal Research |
| Publisher | Department of Forestry, Fisheries and the Environment (2019) |
| Contributors |
Contact Person: Jimmy Khanyile |
| Abstract | Please note: 1. This report has not been peer-reviewed; 2. The conditions of use outlined in the report are superseded by the conditions specified by the License field in this metadata record; 3. The contact information included in the report is superseded by the contact information that can be found in the Responsible Parties field of this metadata record.This is the fifth in a series of informal biannual reports introduced in December 2006, with the intention to establish general principles, such as annual cycles, long-term trends which may provide insight into local effects of global warming and climate change, and to provide an overview of recent marine environmental conditions which may be of relevance to the management of South African marine resources. To this end use is made of data from a variety of sources, including web sources, satellite sensors, the South African Weather Service, MCM's coastal- and moored instruments and MCM's research cruises, and inherent to all of these there is an inevitable lag between the time of data capture and the time when the data first become available for use. The lags are all different. For example, wind data from the Cape Point lighthouse is updated monthly, the moored temperature recorders are serviced every three months and the time series of some satellite data are updated at irregular intervals resulting in lags which may be as long as a year or, in some cases, even several years. Therefore, while it is the aim that the environmental reports should reflect the conditions that prevailed over the months leading up to the reporting date in order to meet the resource management objective, some out-of-date series are incorporated because they provide, for example, information on long-term trends which would otherwise not be available. Also, in addition to observations directly related to local conditions, time series of the Southern Oscillation Index and St Helena Island Index are also provided because they are known, or at least suspected ,of representing global and basin scale processes which affect local conditions.With this issue of the report an index based on the Pathfinder v5 satellite derived sea surface temperature (SST) data set was introduced. This data set is updated annually and is currently a year out of date but it is the longest series of SST data now available. Estimates of Ekman upwelling were improved by adding an index calculated from daily wind components obtained from the Quickscat satellite scatterometer. This index is regarded as more reliable than the previously used upwelling index based on geostrophic wind data, but the older index is retained because it provides a much longer time series. Reporting on dissolved nutrient on the St Helena Bay monitoring line (SHBML) was enhanced by including data on nitrite concentrations. |
| Data | |
| Temporal extent | 01 Jul 2008 – 31 Dec 2008 |
| Geographic extent |
North: -23.77 |
| Keywords | Cape Columbine, Cape Point, Chlorophyll-a, copepod, Ekman upwelling indices, El Niño Southern Oscillation Index, Hondeklip Bay, MBML, Mossel Bay Monitoring Line, nitrate, nitrite, oxygen, phosphate, Phytoplankton, Plettenberg Bay, Sea Surface Temperature, SHBML, silicate, Sodwana Bay, South Africa, SST, St Helena Island Climate Index, St. Helena Bay Monitoring Line, State of the Marine Environment, State of the Ocean, Tsitsikamma, Wind |