Geoscience Reference
In-Depth Information
mode observations including along track sea-level anomalies from altime-
try (T/P, ERS, GFO, Jason, ENVISAT), coastal tide gauges,
in-situ
tem-
perature and salinity profiles (WOCE, TAO, Argo, XBT) and analysed
atmospheric forcing, ERA40.
10
Assimilation is performed every three model
days. BRAN represents the first eddy-resolving ocean analysis for the Aus-
tralian region. Analyses show skill in surface currents as compared with
surface drifter observations.
8
An example of the analysed flow for sea sur-
face temperature is shown in Fig. 3 for the Coral Sea. The three figures
illustrate both the eddy scale variability as well as interannual variability
for January 1, 2000-2002. The extensive warm intrusion shown in 2002 cor-
responds to a year of wide spread coral bleaching in the Great Barrier Reef.
BODAS was parallelised into 40 zonal sections submitted as single pro-
cessor jobs. BODAS uses a stationary set of background error covariance
statistics, which is based on a 72 member ensemble of model anomalies,
O(15) Gbytes.
3.4.
Operational environment
The Bureau's operations branch has the central responsibility for issuing
meteorological analyses and predictions and distributing this information
to the community through a network of regional forecast centers. In addi-
tion to meteorological forecasts, the Bureau also produces a range of other
services in climate, hydrology, and oceanography. Oceanographic services
at present cover a modest range of operational products including, tides,
sea surface and subsurface temperature analyses and wave forecasts. The
implementation of a high-resolution three-dimensional ocean state analysis
and forecast system represents a major upgrade in computational resource
and servicing requirements.
The high performance computational infrastructure that supports the
operations branch is managed through the HPCCC. The core system, an
NEC SX6, is accessed through an NQS based queue system that provides
pre-emptive priority service to operational jobs while still providing ser-
vices for research and development tasks performed by other sections of the
Bureau and CSIRO. The SX6 is front-ended by dual NEC TX7 servers, each
having 16 CPU and 16GB of memory. The TX7s provide global file system
services for the SX6 nodes, and also scalar services for tasks associated with
file transfers and data handling. Access to this common high-performance
computing facility has been critical to the success of the BLUElink
>
project
to date.
