The
CIRENE oceanographic campaign, within the west Indian Ocean will be
synchronized with the VASCO observing system (Aeroclippers and
pressurized balloons launched from the Seychelles). During CIRENE,
physical oceanography, air-sea fluxes and atmospheric measurements will
be collected and a special care will be taken in measuring the diurnal
cycle in the surface layer since it is believed to play an important
role in intraseasonal SST variability. Biogeochemical measurements
(nutrients, pigments) will also be collected because they can provide
useful information on the physical processes at the origin of the SST
perturbation. These measurements will be combined with those from VASCO
and from Provor/Argo floats.
General view of the
Vasco-Cirene campaign
During
the Vasco-Cirene experiment Aeroclippers and
pressurized baloons (pictures below) will be deployed from the
Seychelles and will
sample the region of the Cirene campaign. An ATLAS mooring will be
deployed at 67°E, 8°S during Cirene and the Suroit ship
will be located at 8°S-67°E.
The background indicates the level
of intraseasonal SST variability in winter.
The
Vasco balloons
An aeroclipper (left) and a pressurised balloon (right). The
pressurised balloon measures temperature, humidity and pressure close
to the top of the boundary layer. The aeroclipper is a new system that
takes atmospheric measurements (wind, temperature, humidity, pressure)
~30m above the surface and sea surface measurements
(temperature
and salinity). This makes it possible to estimate turbulent heat ans
water vapour air-sea fluxes along its trajectory using bulk formulae.
The two legs of the Cirene
Campaign
Planned trajectories of the Suroît
during the two legs of the
Cirene campaign in January-February 2007. Both legs last ~20 days and
start and return to the Seychelles. During Cirene, one ATLAS
buoy will
be deployed at 67°E,8°S in collaboration with PMEL with
enhanced measurements during the campaign (surface fluxes, salinity,
currents by ADCP...). A scaled-down version (mostly temperature sensors
and current-meters) will remain there after the campaign. 12 Provor
Argo floats will be deployed as well as three surface
drifters
(collaboration with WHOI). The detailed
evolution of the upper ocean
will be measured using ASIP and by CTD during two 12-day stations close
to the ATLAS mooring. The surface fluxes will be measured continuously
using the CETP/CNRM/DT INSU instrumented
mast. 2 two 4 radiosondes will
be deployed everyday and several boundary layer and atmospheric
measurements will be done continuously in collaboration with RSMAS.
Biogeochemical measurements (nutrients and pigments) will also be
collected.
The Vasco-Cirene Campaign