• Smith and Sandwell v8.2 bottom topography. Detail near 35E and 55E.
• M. Rouault figures of mean 1993-2006 geostrophic currents. Note that these altimetric surface currents are a factor of 2 too weak. Thus the maximum scale should be 1.6 m/s, rather than 0.8 m/s.
• M. Rouault figures of SAR radial currents on 10-Sep-09 21:15UTC, 25-Aug-09 7:23UTC, 22-Aug-09 7:17UTC, 22-Aug-09 7:17UTC, 3-Aug-09 7:15UTC,
• CLS Soprano SAR Ocean Products Demonstration: Mean radial surface currents from 329 ascending Envisat ASAR WSM acquisitions.
• Lutjeharms and Ansorge J. Mar. Sys. 2001: geographic velocities and transport across sections central and terminal regions of ARC Volume transport of ARC along its full length.
• Figures from Park et al. JGR 1993 "Water mass and circulation in the Crozet Basin": Vertical cross-sections of geostrophic currents, Dynamic topography relative to 2500 db during cruise. Stations for the cruise.
• Figures from BoebeletalDSRII 2003 "Path and variability of Agulhas Return Current": RAFOS float trajectories, SSH std, and position of mean SSH 1.5m isoline, shipboard ADCP velocity (21-25m bin) superimposed on SSH for 23Aug97 and RAFOS float trajectories, shipboard ADCP velocity sections, ARC cross-section from interpolated ADCP and RAFOS float data, high velocity histogram map.
• Sallee et al. OcDyn 2006 Map of Average velocity at 400m depth deduced from ARO and PALACE floats.
• K. Speer figure of LADCP profile at 30E 38.5W on 12Feb08
• I6S LADCP LDEO website

• The air-sea flux mooring with CO2 flux and biogeochemical enhancements would monitor the poleward boundary of the Agulhas Somali Current Large Marine Ecosystems (ASCLME) observing system,
  
• The air-sea flux mooring would be combined with the South Atlantic branch of the Meridional Overturning Circulation (SAMOC) array to help quantify the heat exchanges at the choke point between South Africa and Antarctica. Plans for monitoring the South Atlantic component of the MOC are described in the Speich et al. OceanObs09 White Paper.
  
• The air-sea flux mooring would be combined with the Agulhas Current Transport Array to help determine the relation between poleward transport by the western boundary current and surface heat loss in the ARC. The ACT array will be in the water from March 2010-March 2013, afterwhich the transport will be monitored through altimetry.
  

• The mooring could be serviced by the FRS Algoa through partnership with ASCLME.
  

Pros and Cons of different locations:

Retroflection region
Pros: The retroflection has some of the large surface heat losses in the entire region. It is the gateway to the South Atlantic and extremely dynamic.
Cons: It is not clear that a surface mooring could survive the energetic currents found here. For this reason, this region won't be considered further at this time.

55E, 42S (proposed site in original CWP)
Pros: This region has some of the strongest heat fluxes outside of the retroflection region. The currents are likely to be much reduced from those found further west, increasing survivability.
Cons: This site is far to the east of most activities and thus is less connected with partnerships in the Greater Agulhas System. It would also be much more difficult to service.

37E, 38S (proposed site in revised CWP)
Pros: This region has some of strong heat flux (although not the strongest in the region). This site can be considered as an outer boundary for the various observing arrays in the region (e.g. ASCLME, ACT, SAMOC). The site is within the (warm) trough of the second meander in the mean field currents. As such, it will tend to have lower currents and stronger heat loss.
Cons: The location is within the meander envelope, and therefore there is the potential that the jet will "hit" the mooring and that the mooring will find itself on the cold side of the front where heat fluxes are much reduced. The KEO mooring has survived meanders that have shifted over its site. The ARC site however may have more energetic deep flow. We are searching for more information abou tthe deep flow in this region.

30E, 38.5S (possibly better site?)
Pros: This site is just east of the Agulhas Plateau, in the trough of the first meander. The plateau causes the first meander to be very stable so that the site is in fact outside the meander envelope, according to the Boebel et al. DSR 2003 study. It thus has the lowest probability of experiencing extremely strong jet conditions. The heat fluxes are stronger than they are downstream, at least until the Crozet Basin. This site would monitor the (exit?) boundary of the ASCLME. Likewise, the site is well connected with the ACT array and SAMOC line. The site is the closest to South Africa considered here and would have the shortest transit.
Cons: There may be a trade off between the low temporal variability at this location and potentially very large spatial variability (which can be difficult to decipher with a single mooring). The stability of the front may enable a very localized ecosystem to develop in this trough (any supporting studies of this speculation?). It should be noted that while the oceanography may have less temporal variability, the atmosphere will be dominated by synoptic storms with significant temporal variability.

Links to groups and projects working in this region: