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BAMOS
Sept 2017
Figure 2. Evaluation of forecasts from the 12-km reanalysis suite (BARRA-R, shown in green), the 1.5-km downscaled
reanalysis over the Sydney subdomain (BARRA-SY, 37.88 to 28.05 °S and 147.12 to 153.63 °E, shown in red) and ERA-
Interim (shown in blue) against observed screen-level temperature for the period February to March 2010. 6-hour forecasts
of temperature are evaluated at 00 and 12 UTC. Left: Root Mean Square Error (RMSE), right: bias.
Figure 3. Comparison of model daily rainfall from BARRA-R (left) against gauge-interpolated daily rainfall (AWAP) (right)
for 24 August 2010. Model rainfall less than 0.1 mm/day is masked.
the NASA-Global Modelling and Assimilation Office. They found
that the most extreme changes in wind speed are consistently
underestimated in MERRA, with the largest underestimations
associated with high altitude stations. The underestimation
of wind speeds at high elevation is a result of overly smooth
topography, MERRA has a resolution of about 50 km.
Preliminary case studies
The two case studies below highlight examples of potential
benefits from the reanalysis data. The first case derives benefit
from the extensive, consistent spatial coverage of the reanalysis
data. The second case study derives benefit from the potentially
more accurate wind data available with fine-scale coverage in
the reanalysis. This is an exciting area of further research.
Bushfire in Tasmania – The Giblin River fire
Details of the Giblin River Fire event are documented in
Marsden-Smedley (2014). The fire was started by lightning in
the afternoon of 3 January 2013. Due to the remoteness of the
location, no attempts were made suppress the fire. The fire then
spread over the following weeks and continued to burn slowly
until it was contained almost three weeks later (22 January
2013), having burned an area of approximately 450 km 2 (Figure
4).
The orography in this region strongly affects wind conditions
during fire events and the reanalysis can provide information
that is not readily available on the basis of surface observations
alone (Figure 5). Data is shown from the Giblin River fire where
a lack of any